Conversion of legumes, cereals and nuts into calorie-reduced protein systems as a starting point for dry and wet extrusion

Abstract

The invention relates to a process for the preparation of a protein composition comprising the steps of: (a) providing an educt protein composition comprising water, protein and starch; (b) hydrolyzing at least a portion of the starch contained in the educt protein composition with catalysis by means of a first amylolytic enzyme, thereby providing a first intermediate composition comprising water, protein, glucose, optionally starch, and optionally maltose; (c) optionally, hydrolyzing at least a portion of the maltose contained in the first intermediate composition with catalysis by means of a second amylolytic enzyme, thereby providing a second intermediate composition comprising water, protein, glucose, and optionally starch; and (d) oxidizing at least a portion of the glucose contained in the first intermediate composition or the second intermediate composition with catalysis by means of a glucose oxidase thereby providing a protein composition comprising water, protein, gluconic acid, optionally starch, and optionally glucose.

Description

Conversion of legumes, cereals and nuts into calorie-reduced protein systems as a starting point for dry and wet extrusion

[0001] Priority is claimed of European patent application no. 25 160018.5 that was filed on 25 February 2025.

[0002] The invention relates to a process for the preparation of a protein composition comprising the steps of: (a) providing an educt protein composition comprising water, protein and starch; (b) hydrolyzing at least a portion of the starch contained in the educt protein composition with catalysis by means of a first amylolytic enzyme, thereby providing a first intermediate composition comprising water, protein, glucose, optionally starch, and optionally maltose; (c) optionally, hydrolyzing at least a portion of the maltose contained in the first intermediate composition with catalysis by means of a second amylolytic enzyme, thereby providing a second intermediate composition comprising water, protein, glucose, and optionally starch; and (d) oxidizing at least a portion of the glucose contained in the first intermediate composition or the second intermediate composition with catalysis by means of a glucose oxidase thereby providing a protein composition comprising water, protein, gluconic acid, optionally starch, and optionally glucose.

[0003] Plant proteins are nowadays used for a variety of meat substitute products. This is partly due to increased demand for a vegetarian or vegan diet and partly due to the consumer demand for sustainable and resource-conserving agriculture.

[0004] One of the advantages of vegan food products made from plant-based proteins is that they can be produced from domestic or locally sourced raw materials. Endemic plant varieties also have the advantage that they are often adapted to the respective climatic conditions, so that they can be cultivated in a more resource-efficient way than imported plant varieties. On the other hand, there is a growing demand for various plant-based food products.

[0005] Traditionally, products based on plant proteins are manufactured by dry or wet extrusion. Dry extrusion is carried out at high temperatures T > 130 °C and a moisture content < 30 %. A short, narrow die without cooling is used for extrusion. This enables the production of directly expanded products, so-called TVP (texturised vegetable proteins). In dry form, they are rather irregular, porous and glassy and, after being rehydrated, are further processed into the end products. Although they are referred to as textured products, the end product has a sponge-like structure without significant anisotropy, with either no fibers or only very short fibers. They only slightly resemble the sensory properties of meat analogues and are often used in mixed products (e.g. burger patties etc.) and not for whole products.

[0006] High moisture extrusion (HME) is the current technology used by the industry to produce fibrous plant protein-based products. The resulting products often provide a satisfactory basis as theyhave an anisotropic, meat-like structure, texture and appearance. Such products are manufactured using various technologies, but have a higher water content of more than 50% by weight compared to the dry extrusion products mentioned above.

[0007] In this type of wet extrusion, the mass is pressed through an elongated cooling slot die or an elongated cooling couette die after kneading. In both cases, the protein-based matrix is extruded at relatively high temperatures (T > 130 °C) and high water contents (>50 %) in the screw section of the extruder and then forced to flow through a downstream cooling die, in which the material is continuously cooled (typically to below <100 °C at the die outlet) in order to avoid expansion, which could destroy the produced fibrous structures in the die section. The products obtained will be more intended for producing finished products for immediate consumption that simulate animal meat, for example, beef steaks or chicken nuggets. For example, patent application WO 2014 / 081285 is known, which discloses a method for extruding a mixture of protein and fibers using a cooling die typical of wet extrusion.

[0008] Historically, the first proteins used as meat substitute products were extracted from soybean and wheat. Soybean subsequently quickly became the main source for this field of applications.

[0009] While most of the studies that followed related to soybean proteins, other sources of protein, both animal and plant, have been textured: peanut, sesame, cottonseed, sunflower, com, wheat proteins, proteins derived from microorganisms, by-products from abattoirs or the fisheries industry.

[0010] Leguminous proteins, such as those derived from pea and faba bean, have also been the subject of studies, both in terms of the isolation thereof and in terms of the extrusion thereof, see for example T. Kim et al. J. FoodSci. 2021;86:1322-1334.

[0011] US 4259358 A relates to a process wherein an aqueous slurry of legume seeds is subjected to amylolytic enzyme treatment, preferably by alpha-amylase followed by amyloglucosidase. The dry starting material or the slurry may be divided into protein-enhanced and protein-depleted fractions to facilitate treatment. Lipid and / or methionine derivatives may also be added, and the resultant product optionally treated with aldehyde. The products find application as milk-replacers, food ingredients and foods for human and non-human mammals.

[0012] US 9 675 084 B2 discloses methods for reducing color and / or unpleasant taste and / or malodor development in a composition comprising a plant material, such a cereal bran, in particular during solubilization processes of the plant material.

[0013] US 2024 / 057636 Al relates to oat protein compositions and production method thereof and in particular to a method of production of an oat protein composition from oat milk co-products.

[0014] US 2024 / 397969 Al discloses a process for concentrating plant-based protein, a plant-based protein concentrate obtainable with the process, to food products including said plant -based concentrate and uses thereof.

[0015] EP 1 915 061 relates to granulated pea protein composition characterized in that the protein content expressed in terms of a dry substance ranges from 70 to 95 % by dry weight, preferably from 70 to 90 % by dry weight, more preferably from 80 to 85 % by dry weight, a mean diameter ranges from 150 to 300 pm, a compressibility value determined by the HOSOKAWA method ranges from 5 to 15%, preferably from 8 to 13% and a tamped density determined by the HOSOKAWA method ranges from 0.450 and 0.650 g / ml, preferably from 0.550 and 0.650 g / ml. The method for producing said granulated pea protein composition, the use thereof in the form of a raw material for producing textured pea proteins and the thus obtainable textured pea proteins are also disclosed.

[0016] EP 3 349 591 relates to a meat substitute comprising two or more sources of plant protein, or a meat substitute comprising one more sources of plant protein and a fruit, fruit powder, or chia seed extract, or a low allergen meat substitute that is optionally free of soy and optionally free of other allergenic ingredients.

[0017] EP 4 110079 relates to a composition comprising leguminous proteins which have been textured in a dry process, to a method for preparing same and to the use thereof.

[0018] WO 2021 / 030286 relates to plant-based nutritional compositions comprising fava bean protein isolate and pea protein. The fava bean protein isolate comprises greater than about 10 wt% of the total protein in the composition, and the pea protein comprises less than about 50 wt% of the total protein in the composition. The nutritional compositions are high in protein, high in fiber, and low in calories and the compositions may be dairy-free and / or soy -free.

[0019] WO 2024 / 188907 relates to a protein-containing texturate which is characterised by a special anisotropy comparable to meat. The texturate comprises a first protein mixture with a non-legume protein, in particular wheat protein, with a proportion of between 10 wt.% and 90 wt.% of the dry mass, and a second protein mixture, in particular with a legume protein or a side-stream product, with a proportion of between 10 wt.% and 90 wt.% of the dry mass. The moisture content is less than 40 wt.% and in particular less than 35 wt.%; a protein proportion of the texturate is between 35 wt.% and 60 wt.% of the dry mass. The texturate has fibres with a preferred direction and a length of more than 10 mm and in particular more than 15 mm, and has an anisotropy index of greater than 1 and in particular greater than 1.4.

[0020] The processes and plant-based food products of the prior art are not satisfactory in every respect and there is a demand for improved processes for the preparation of plant-based food products.

[0021] Off notes, often described as an objectionable taste and / or odor, are a widespread problem in plant-based food products. Off notes are caused by plant proteins, which can create a lingering after taste and bitterness in meat alternatives. Manufacturers often mask these unfavorable attributes with a combination of flavors, however this can in turn result in an undesirable aroma from the food.

[0022] It is an object of the invention to provide plant-based food products and a process for the preparation thereof having advantages compared to the plant-based food products and processes of the prior art. In particular, it is an object of the invention to provide a protein composition as a starting point for the preparation of plant-based food products. The protein composition should be extrudable by wet and dry extrusion to provide plant-based food products.

[0023] This object has been achieved by the subject-matter of the patent claims.

[0024] It has been surprisingly found that calorie-reduced protein compositions as starting material for the preparation of plant-based food products can be provided by converting starch into glucose and subsequently gluconic acid. The protein compositions are extrudable by wet and dry granulation to obtain plant-based food products. It has been found that converting starch to glucose and subsequently to gluconic acid can be advantageously achieved by enzymes.

[0025] Further, it has been surprisingly found that extrusion of the protein compositions is improved if the starch content is less. Without wishing to be bound to any scientific theory, it appears that extrusion is improved when the protein content of the protein composition is higher and because starch may be more of a disruptive factor in protein cross-linking.

[0026] Still further, it has been surprisingly found that gluconic acid optimizes taste of plant-based food products. It has been found that the pleasant taste of gluconic acid can mask the frequently occurring off-flavors in plants such as legumes and cereals in plant-based food products. For example, the need to add flavor-altering substances such as spices or flavorings is eliminated (or greatly reduced) both during the preparation of the plant-based food product and, in particular, during further processing. Thus, calorie reduced plant-based food products can be provided having improved taste.

[0027] Moreover, it has been surprisingly found that protein compositions with reduced starch content and comprising gluconic acid may lead to improved plant-based food products that have e.g. improved color or can e.g. be prepared by more stable processes.

[0028] A first aspect of the invention relates to a process for the preparation of a protein composition comprising the steps of:(a) providing an educt protein composition comprising or essentially consisting of water, protein and starch;(b) hydrolyzing at least a portion of the starch contained in the educt protein composition with catalysis by means of a first amylolytic enzyme, thereby providing a first intermediate composition comprising or essentially consisting of water, protein, glucose, optionally starch, and optionally maltose;(c) optionally, hydrolyzing at least a portion of the maltose contained in the first intermediate composition with catalysis by means of a second amylolytic enzyme, thereby providing a secondintermediate composition comprising or essentially consisting of water, protein, glucose, and optionally starch; and(d) oxidizing at least a portion of the glucose contained in the first intermediate composition or the second intermediate composition with catalysis by means of a glucose oxidase thereby providing a protein composition comprising or essentially consisting of water, protein, gluconic acid, optionally starch, and optionally glucose.

[0029] For the purpose of the specification, unless expressly stated otherwise, percentages are percent by weight. Unless expressly stated otherwise, any norms such as EN ISO, ASTM and the like are in the official version that is valid on January 1, 2024.

[0030] The expression "essentially consists of' means a content of at least about 95 wt.-%, preferably at least about 99 wt.-%, relative to the total weight of the component to which the definition refers.

[0031] In the process according to the invention, the starch content of the educt protein composition is reduced by converting starch at least partially to glucose and subsequently at least partially to gluconic acid, thereby providing the protein composition. The protein composition according to the invention is a starting material for the preparation of plant-based food products. The plant-based food products can preferably be prepared by wet or dry extrusion of the protein composition (protein blend).

[0032] The process according to the invention is preferably an enzymatic process.

[0033] The process according to the invention can be carried out in one stage as a one-pot process and / or in two or three stages as a one-, two- or three-pot process. In one stage in this context means that step (b), optionally step (c), and step (d) of the process according to the invention take place simultaneously. Correspondingly, in two stages means that steps (b) and (d), or steps (b) and (c), or steps (c) and (d) of the process according to the invention take place temporally in succession. In three stages means that steps (b), (c) and (d) of the process according to the invention take place temporally in succession. A person skilled in the art will appreciate that mixed forms with partial concurrence are also possible.

[0034] In step (a) of the process according to the invention the educt protein composition comprising or essentially consisting of water, protein and starch is provided.

[0035] Preferably, step (a) of the process according to the invention comprises the sub-steps of (ai) providing a protein source;(a2) optionally, grinding, milling or concentrating the protein source; and(as) mixing the optionally grinded, milled or concentrated protein source with water thereby providing the educt protein composition.

[0036] The protein contained in the educt protein composition is preferably provided by the protein source. Preferably, the protein source is selected from plant fruits, plant seeds, plant flour, plant protein concentrate, plant protein isolate, and mixtures thereof; preferably plant flour or plant protein concentrate.

[0037] Typically plant flour, plant protein concentrate and plant protein isolate differ in the protein content. Plant flour preferably has a protein content within the range of from 40 to 50 wt.-%. Plant protein concentrate preferably has a protein content within the range of from 60 to 70 wt.-%. Plant protein isolate preferably has a protein content within the range of from 80 to 90 wt.-%.

[0038] Preferably, the plant of the protein source is selected from legumes, cereals, nuts, fungi, algae, and mixtures thereof; preferably from legumes, cereals, nuts, and mixtures thereof; more preferably from beans, preferably soybeans, mung beans, cowpeas or faba beans, peas, chickpeas, lupines, lentils, peanuts, almonds, brazil nuts, cashews, chestnuts, hazelnuts, pecans, pine nuts, walnuts, rice, wheat, rye, oats, barley, millet, maize, and mixtures thereof.

[0039] Preferably, the plant of the protein source is legumes; preferably pulses; more preferably selected from beans, preferably soybeans, mung beans, cowpeas or faba beans, peas, chickpeas, lupines, lentils, peanuts, and mixtures thereof; more preferably faba beans, peas, lentils and mixtures thereof.

[0040] Preferably, the plant of the protein source is cereals; preferably selected from rice, wheat, rye, oats, barley, millet, maize, and mixtures thereof; more preferably wheat.

[0041] In preferred embodiments, the protein source is faba bean flour (fava bean flour) or faba bean concentrate.

[0042] In other preferred embodiments, the protein source is lentil flour or lentil concentrate.

[0043] Preferably, the protein source is also the starch source for the educt protein composition.

[0044] Preferably, the educt protein composition is a mixture of the protein source and water.

[0045] Preferably, the educt protein composition is a liquid; preferably a suspension.

[0046] The educt protein composition according to the invention comprises water.

[0047] In preferred embodiments, the weight content of water in the educt protein composition is at least 10 wt.-%; preferably at least 12.5 wt.-%, more preferably at least 15 wt.-%, still more preferably at least 17.5 wt.-%, yet more preferably at least 20 wt.-%, even more preferably at least 22.5 wt.-%, most preferably at least 25 wt.-%, and in particular at least 30 wt.-%; in each case relative to the total weight of the educt protein composition.

[0048] In preferred embodiments, the weight content of water in the educt protein composition is at most 40 wt.-%; preferably at most 35 wt.-%, more preferably at most 30 wt.-%, still more preferably atmost 27 wt.-%, yet more preferably at most 24 wt.-%, even more preferably at most 21 wt.-%, most preferably at most 18 wt.-%, and in particular at most 15 wt.-%; in each case relative to the total weight of the educt protein composition.

[0049] In preferred embodiments, the weight content of water in the educt protein composition is within the range of from 5.0 to 45 wt.-%; preferably from 7.5 to 40 wt.-%, more preferably from 10 to 35 wt.-%, still more preferably from 12.5 to 30 wt.-%, and yet more preferably from 15 to 25 wt.-%; in each case relative to the total weight of the educt protein composition.

[0050] Preferably, the concentration of dry matter, i.e. including protein, starch and all other dissolved constituents but no water, in the educt protein composition is within the range of from 55 to 95 wt.-%, based on the total weight of the educt protein composition. In preferred embodiments, said concentration is within the range of from 65 to 92.5 wt.-%, preferably from 70 to 90 wt.-%, and more preferably from 75 to 85 wt.-%, in each case based on the total weight of the educt protein composition.

[0051] The educt protein composition according to the invention comprises protein.

[0052] Preferably, the protein is plant protein; preferably selected from leguminous protein, cereal protein, nut protein, fungi protein, algae protein, and mixtures thereof; preferably leguminous protein, cereal protein, nut protein, and mixtures thereof.

[0053] In preferred embodiments, the protein is leguminous protein; preferably pulse protein; more preferably selected from bean protein, preferably soybean protein, mung bean protein, cowpea protein or faba bean protein, pea protein, chickpea protein, lupine protein, lentil protein, peanut protein, and mixtures thereof; more preferably faba bean protein, pea protein, lentil protein and mixtures thereof.

[0054] In preferred embodiments, the weight content of protein in the educt protein composition is at least 30 wt.-%; preferably at least 35 wt.-%, more preferably at least 40 wt.-%, still more preferably at least 45 wt.-%, yet more preferably at least 50 wt.-%, even more preferably at least 55 wt.-%, most preferably at least 60 wt.-%, and in particular at least 65 wt.-%; in each case relative to the total content of dry matter that is contained in the educt protein composition.

[0055] In preferred embodiments, the weight content of protein in the educt protein composition is at most 86 wt.-%; preferably at most 83 wt.-%, more preferably at most 80 wt.-%, still more preferably at most 77 wt.-%, yet more preferably at most 74 wt.-%, even more preferably at most 71 wt.-%, most preferably at most 68 wt.-%, and in particular at most 65 wt.-%; in each case relative to the total content of dry matter that is contained in the educt protein composition.

[0056] In preferred embodiments, the weight content of protein in the educt protein composition is within the range of from 35 to 90 wt.-%; preferably from 40 to 85 wt.-%, more preferably from 45 to 80 wt.-%, still more preferably from 50 to 75 wt.-%, yet more preferably from 55 to 70 wt.-%, even morepreferably from 60 to 65 wt.-%; in each case relative to the total content of dry matter that is contained in the educt protein composition.

[0057] The educt protein composition according to the invention comprises starch.

[0058] In preferred embodiments, the weight content of starch in the educt protein composition is at least 1.0 wt.-%; preferably at least 3.0 wt.-%, more preferably at least 5.0 wt.-%, still more preferably at least 7.0 wt.-%, yet more preferably at least 9.0 wt.-%, even more preferably at least 11 wt.-%, most preferably at least 13 wt.-%, and in particular at least 15 wt.-%; in each case relative to the total content of dry matter that is contained in the educt protein composition.

[0059] In preferred embodiments, the weight content of starch in the educt protein composition is at most 55 wt.-%; preferably at most 50 wt.-%, more preferably at most 45 wt.-%, still more preferably at most 40 wt.-%, yet more preferably at most 35 wt.-%, even more preferably at most 30 wt.-%, most preferably at most 25 wt.-%, and in particular at most 20 wt.-%; in each case relative to the total content of dry matter that is contained in the educt protein composition.

[0060] In preferred embodiments, the weight content of starch in the educt protein composition is within the range of from 1.0 to 35 wt.-%; preferably from 3.0 to 32 wt.-%, more preferably from 6.0 to 29 wt.-%, still more preferably from 9.0 to 26 wt.-%, yet more preferably from 12 to 23 wt.-%, even more preferably from 15 to 20 wt.-%; in each case relative to the total content of dry matter that is contained in the educt protein composition.

[0061] In preferred embodiments, the relative weight ratio of protein to starch in the educt protein composition is within the range of from 1.0 : 1.0 to 15 : 1.0, preferably from 1.5 : 1.0 to 13 : 1.0, more preferably from 2.0 : 1.0 to 11 : 1.0, still more preferably from 2.5 : 1.0 to 9.0 : 1.0, yet more preferably from 3.0 : 1.0 to 7.0 : 1.0, and even more preferably from 3.0 : 1.0 to 5.0 : 1.0.

[0062] In step (b) of the process according to the invention at least a portion of the starch contained in the educt protein composition is hydrolyzed with catalysis by means of a first amylolytic enzyme, thereby providing a first intermediate composition comprising or essentially consisting of water, protein, glucose, optionally starch, and optionally maltose. Thus, in step (b) of the process according to the invention the starch content contained in the educt protein composition is reduced.

[0063] For the purpose of the specification, "starch" is a polymeric carbohydrate consisting of glucose units joined by glycosidic bonds (polysaccharide). Starch within the meaning of the invention essentially consists of two types of molecules: amylose and amylopectin. Amylose within the meaning of the invention consists of long chains derived from glucose molecules connected by alpha- 1,4-glycosidic linkage. Amylopectin within the meaning of the invention consists of long chains derived from glucose molecules connected by alpha- 1,4-glycosidic linkage but also interconnected by alpha-1, 6-glycosidic linkages. Thus, the structure of amylose is linear and helical, whereas amylopectin is branched.

[0064] Preferably, hydrolyzation of starch involves breaking starch molecules into simpler sugars (oligo-, di- and / or monosaccharides), preferably glucose and optionally maltose. It is contemplated that the first and second intermediate composition according to the invention may comprise reaction products from the hydrolysis of starch other than glucose and optionally maltose, for example isomaltose, maltotriose and dextrins. According to the invention, the term "oligosaccharide" includes trisaccharides and longer-chained saccharides with up to ten monosaccharide units. If the D- or L-form is not mentioned expressly, then according to the invention it is preferably in each case the D-form.

[0065] In preferred embodiments, in step (b) at least 5.0 wt.-% of the starch contained in the educt protein composition is hydrolyzed; preferably at least 10 wt.-%, more preferably at least 15 wt.-%, still more preferably at least 20 wt.-%, yet more preferably at least 25 wt.-%, even more preferably at least 30 wt.-%, most preferably at least 35 wt.-%, and in particular at least 40 wt.-%; in each case relative to the total weight of starch contained in the educt protein composition.

[0066] In preferred embodiments, step (b) of the process according to the invention is performed at a temperature of at least 50 °C; preferably at least 55 °C, more preferably at least 60 °C, still more preferably at least 65 °C, and yet more preferably at least 70 °C.

[0067] In preferred embodiments, step (b) of the process according to the invention is performed at a temperature of at most 70 °C; preferably at most 65 °C, more preferably at most 60 °C, still more preferably at most 55 °C, and yet more preferably at most 50 °C.

[0068] Preferably, step (b) of the process according to the invention is performed at a temperature within the range of from 25 to 85 °C; preferably from 30 to 82 °C, more preferably from 35 to 79 °C, still more preferably from 40 to 76 °C, yet more preferably from 45 to 73 °C, even more preferably from 50 to 70 °C.

[0069] In preferred embodiments, step (b) of the process according to the invention is performed at a pH-value of at least 4.0; preferably at least 4.2, more preferably at least 4.4, still more preferably at least 4.6, yet more preferably at least 4.8; and even more preferably at least 5.0.

[0070] In preferred embodiments, step (b) of the process according to the invention is performed at a pH-value of at most 4.0; preferably at most 4.2, more preferably at most 4.4, still more preferably at most 4.6, yet more preferably at most 4.8; and even more preferably at most 5.0.

[0071] Preferably, step (b) of the process according to the invention is performed at a pH-value within the range of from 2.5 to 6.5; preferably from 2.8 to 6.2, more preferably from 3.1 to 5.9, still more preferably from 3.4 to 5.6, yet more preferably from 3.7 to 5.3, even more preferably from 4.0 to 5.0.

[0072] Preferably, step (b) of the process according to the invention is performed for a duration within the range of from 10 to 170 minutes; preferably from 20 to 160 minutes, more preferably from 30 to 150minutes, still more preferably from 40 to 140 minutes, yet more preferably from 50 to 130 minutes, even more preferably from 60 to 120 minutes.

[0073] Preferably, step (b) of the process according to the invention does not require oxygen, in particular the first amylolytic enzyme does not require oxygen for its activity. Thus, in preferred embodiments, step (b) of the process according to the invention is performed without oxygen supply; preferably step (b) of the process according to the invention is performed under vacuum atmosphere.

[0074] Preferably, step (b) of the process according to the invention comprises the sub-step of (bi) adding the first amylolytic enzyme to the educt protein composition.

[0075] Preferably, only the first amylolytic enzyme is added to the educt protein composition.

[0076] Preferably, no xylanase, cellulase, or glucanase is added to the educt protein composition.

[0077] In preferred embodiments, no catalase is added to the educt protein composition.

[0078] Preferably, no further hydrolytic enzyme or enzymatic antioxidant is added to the educt protein composition.

[0079] Preferably, no cell-wall modifying enzyme (CWME) is added to the educt protein composition.

[0080] Preferably, no protein-modifying enzyme is added to the educt protein composition.

[0081] Preferably, the first amylolytic enzyme is selected from amyloglucosidase, alpha-amylase, betaamylase, gamma-amylase, isoamylase, pullulanase, and amylopullulanase; preferably alpha-amylase or amyloglucosidase; more preferably alpha-amylase.

[0082] Preferably, the first amylolytic enzyme is inactivated after hydrolyzing at least a portion of the starch contained in the educt protein composition; preferably by means of heating and / or change of the pH-value. Methods to inactivate enzymes are known to the skilled person. Preferably, when the process according to the invention is carried out in one stage as a one-pot process, the first amylolytic enzyme, optionally the second amylolytic enzyme, and the glucose oxidase are inactivated simultaneously. Preferably, when the process according to the invention is carried out in two or three stages as a two- or three-pot process, the first amylolytic enzyme, optionally the second amylolytic enzyme and / or the glucose oxidase are inactivated temporally in succession.

[0083] For the purpose of the specification, an "amylolytic enzyme" catalyzes the hydrolysis of starch into simpler sugars (oligo-, di- and / or monosaccharides). Preferably, the first amylolytic enzyme can cleave and break down polysaccharides such as starch at the glycosidic bonds, preferably alpha- 1,4-glycosidic bonds. Preferably, the hydrolysis of starch by the first amylolytic enzyme yields maltotriose and / or maltose from amylose; and / or maltose, glucose and / or dextrins such as (alpha) limit dextrin from amylopectin.

[0084] For the purpose of the specification, a "cell-wall modifying enzyme" is an enzyme that catalyzes the degradation or modification of the structural polysaccharides that form the plant cell wall. The primary components of the plant cell wall are cellulose, hemicellulose, and pectin. The purpose of these enzymes is to break down this matrix. Examples of cell-wall modifying enzymes include hemicellulases, such as xylanase, (beta-)glucanase, arabinofuranosidase, galactanase, mannanase, feruloyl esterase, and xyloglucanase, cellulases, such as cellulase, endoglucanase, cellobiohydrolase, beta-glucosidase, and pectinases, such as pectinase.

[0085] For the purpose of the specification, a "protein-modifying enzyme" is an enzyme that catalyzes the modification or degradation of proteins, most commonly through the hydrolysis of peptide bonds. The most prominent members of this class are proteases, such as endopeptidases (proteinases) and exopeptidases. Examples of endopeptidases include trypsin, chymotrypsin, pepsin, papain, and bromelain. Examples of exopeptidases include carboxypeptidases and aminopeptidases.

[0086] Preferably, in the process according to the invention, the starch contained within plant cells is hydrolyzed, while preferably leaving the protein and cell wall structures largely intact for later texturization via extrusion. Degrading the protein would be counterproductive to achieving a fibrous, meat-like structure during extrusion.

[0087] In preferred embodiments, the weight content of the first amylolytic enzyme in the educt protein composition is within the range of from 0.01 to 4.0 wt.-%; preferably from 0.05 to 3.0 wt.-%, more preferably from 0.1 to 2.5 wt.-%, still more preferably from 0.25 to 2.0 wt.-%, and yet more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total weight of the educt protein composition.

[0088] In preferred embodiments, the total weight content of enzyme in the educt protein composition is within the range of from 0.01 to 4.0 wt.-%; preferably from 0.05 to 3.0 wt.-%, more preferably from 0.1 to 2.5 wt.-%, still more preferably from 0.25 to 2.0 wt.-%, and yet more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total weight of the educt protein composition.

[0089] In step (b) of the process according to the invention a first intermediate composition comprising or essentially consisting of water, protein, glucose, optionally starch, and optionally maltose is provided.

[0090] Preferably, the first intermediate composition is a liquid; preferably a suspension.

[0091] The first intermediate composition according to the invention comprises water. Preferably, the weight content of water in the first intermediate composition is the same or less as the weight content of water in the educt protein composition.

[0092] Preferably, the concentration of dry matter, i.e. including protein, glucose, optionally starch, optionally maltose and all other dissolved constituents but no water, in the first intermediate composition is within the range of from 55 to 95 wt.-%, based on the total weight of the first intermediate composition. In preferred embodiments, said concentration is within the range of from 65 to 92.5 wt.-%, preferably from 70 to 90 wt.-%, and more preferably from 75 to 85 wt.-%, in each case based on the total weight of the first intermediate composition.

[0093] The first intermediate composition according to the invention comprises protein. Preferably, the weight content of protein in the first intermediate composition is the same or more as the weight content of protein in the educt protein composition.

[0094] In preferred embodiments, the weight content of protein in the first intermediate composition is within the range of from 45 to 95 wt.-%; preferably from 50 to 91 wt.-%, more preferably from 55 to 87 wt.-%, still more preferably from 60 to 83 wt.-%, yet more preferably from 65 to 79 wt.-%, even more preferably from 70 to 75 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

[0095] The first intermediate composition according to the invention optionally comprises starch. Preferably, the starch contained in the first intermediate composition is remaining starch, which was not hydrolyzed in step (b) of the process according to the invention.

[0096] In preferred embodiments, the weight content of starch in the first intermediate composition is at least 1.0 wt.-%; preferably at least 1.5 wt.-%, more preferably at least 2.0 wt.-%, still more preferably at least 2.5 wt.-%, yet more preferably at least 3.0 wt.-%, even more preferably at least 3.5 wt.-%, most preferably at least 4.0 wt.-%, and in particular at least 5.0 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

[0097] In preferred embodiments, the weight content of starch in the first intermediate composition is at most 45 wt.-%; preferably at most 40 wt.-%, more preferably at most 35 wt.-%, still more preferably at most 30 wt.-%, yet more preferably at most 25 wt.-%, even more preferably at most 20 wt.-%, most preferably at most 15 wt.-%, and in particular at most 10 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

[0098] In preferred embodiments, the weight content of starch in the first intermediate composition is within the range of from 0.5 to 25 wt.-%; preferably from 1.0 to 22 wt.-%, more preferably from 2.0 to 19 wt.-%, still more preferably from 3.0 to 16 wt.-%, yet more preferably from 4.0 to 13 wt.-%, even more preferably from 5.0 to 10 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

[0099] Preferably, the weight content of starch in the first intermediate composition is reduced compared to the weight content of starch in the educt protein composition.

[0100] In preferred embodiments, the relative weight ratio of protein to starch in the first intermediate composition is within the range of from 2.0 : 1.0 to 25 : 1.0, preferably from 3.0 : 1.0 to 23 : 1.0, more preferably from 4.0 : 1.0 to 21 : 1.0, still more preferably from 5.0 : 1.0 to 19 : 1.0, yet more preferably from 6.0 : 1.0 to 17 : 1.0, and even more preferably from 7.0 : 1.0 to 15 : 1.0.

[0101] The first intermediate composition according to the invention comprises glucose.

[0102] In preferred embodiments, the weight content of glucose in the first intermediate composition is at least 0.5 wt.-%; preferably at least 0.75 wt.-%, more preferably at least 1.0 wt.-%, still more preferably at least 1.5 wt.-%, yet more preferably at least 2.0 wt.-%, even more preferably at least 2.5 wt.-%, most preferably at least 3.0 wt.-%, and in particular at least 3.5 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

[0103] In preferred embodiments, the weight content of glucose in the first intermediate composition is at most 8.0 wt.-%; preferably at most 7.5 wt.-%, more preferably at most 7.0 wt.-%, still more preferably at most 6.5 wt.-%, yet more preferably at most 6.0 wt.-%, even more preferably at most 5.5 wt.-%, most preferably at most 5.0 wt.-%, and in particular at most 4.5 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

[0104] In preferred embodiments, the weight content of glucose in the first intermediate composition is within the range of from 1.0 to 7.0 wt.-%; preferably from 1.5 to 6.5 wt.-%, more preferably from 2.0 to 6.0 wt.-%, still more preferably from 2.5 to 5.5 wt.-%, yet more preferably from 3.0 to 5.0 wt.-%, even more preferably from 3.5 to 4.5 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

[0105] Preferably, the glucose content is measured with a glucometer.

[0106] The first intermediate composition according to the invention optionally comprises maltose.

[0107] In preferred embodiments, the weight content of maltose in the first intermediate composition is within the range of from 0.01 to 4.0 wt.-%; preferably from 0.05 to 3.5 wt.-%, more preferably from 0.1 to 3.0 wt.-%, still more preferably from 0.15 to 2.5 wt.-%, yet more preferably from 0.2 to 2.0 wt.-%, even more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

[0108] The first intermediate composition according to the invention preferably comprises or essentially consists of- 5.0 to 35 wt.-% water; preferably 15 to 25 wt.-%, relative to the total weight of the first intermediate composition;- 60 to 85 wt.-% protein; preferably 70 to 75 wt.-%;- optionally, 1.0 to 15 wt.-% starch; preferably 5.0 to 10 wt.-%- 2.0 to 6.0 wt.-% glucose; preferably 3.5 to 4.5 wt.-%; and- optionally 0.01 to 4.0 wt.-% maltose; preferably 0.5 to 1.5 wt.-%;in each case relative to the total content of dry matter that is contained in the first intermediate composition.

[0109] In step (c) of the process according to the invention at least a portion of the maltose optionally contained in the first intermediate composition is hydrolyzed with catalysis by means of a second amylolytic enzyme, thereby providing a second intermediate composition comprising or essentially consisting of water, protein, glucose, and optionally starch. Thus, in step (c) of the process according to the invention the maltose content contained in the first intermediate composition is reduced.

[0110] Preferably, in step (c) of the process according to the invention maltose is hydrolyzed to glucose .

[0111] In preferred embodiments, in step (c) at least 20 wt.-% of the maltose contained in the first intermediate composition is hydrolyzed; preferably at least 25 wt.-%, more preferably at least 30 wt.-%, still more preferably at least 40 wt.-%, yet more preferably at least 50 wt.-%, even more preferably at least 60 wt.-%, most preferably at least 70 wt.-%, and in particular at least 80 wt.-%; in each case relative to the total weight of maltose contained in the first intermediate composition.

[0112] Preferably, step (c) of the process according to the invention is performed at a temperature within the range of from 10 to 65 °C; preferably from 15 to 60 °C, more preferably from 20 to 55 °C, still more preferably from 25 to 50 °C, yet more preferably from 30 to 45 °C, even more preferably from 35 to 40 °C.

[0113] Preferably, step (c) of the process according to the invention is performed at a pH-value within the range of from 5.0 to 8.7; preferably from 5.3 to 8.4, more preferably from 5.6 to 8.1, still more preferably from 5.9 to 7.8, yet more preferably from 6.2 to 7.5, even more preferably from 6.5 to 7.2.

[0114] Preferably, step (c) of the process according to the invention is performed for a duration within the range of from 10 to 150 minutes; preferably from 15 to 140 minutes, more preferably from 20 to 130 minutes, still more preferably from 25 to 120 minutes, yet more preferably from 30 to 110 minutes, even more preferably from 40 to 100 minutes.

[0115] Preferably, step (c) of the process according to the invention does not require oxygen, in particular the second amylolytic enzyme does not require oxygen for its activity. Thus, in preferred embodiments, step (c) of the process according to the invention is performed without oxygen supply; preferably step (c) of the process according to the invention is performed under vacuum atmosphere.

[0116] Preferably, step (c) of the process according to the invention comprises the sub-step of (ci) adding the second amylolytic enzyme to the first intermediate composition.

[0117] Preferably, only the first amylolytic enzyme is added to the first intermediate composition.

[0118] Preferably, no xylanase, cellulase, or glucanase is added to the first intermediate composition.

[0119] In preferred embodiments, no catalase is added to the first intermediate composition.

[0120] Preferably, no further hydrolytic enzyme or enzymatic antioxidant is added to the first intermediate composition.

[0121] Preferably, no cell-wall modifying enzyme (CWME) is added to the first intermediate composition.

[0122] Preferably, no protein-modifying enzyme is added to the first intermediate composition.

[0123] In preferred embodiments, the second amylolytic enzyme is selected from glucosidases or maltose binding protein; preferably alpha-glucosidase, beta-glucosidase and maltose binding protein; more preferably alpha-glucosidase; still more preferably maltase-glucoamylase, acid alpha-glucosidase, and neutral alpha-glucosidase C; yet more preferably maltase-glucoamylase.

[0124] The second amylolytic enzyme preferably catalyzes the hydrolysis of terminal glucose residues, preferably of alpha- 1,4-linked glucose residues with release of glucose, preferably alpha-glucose. The second amylolytic enzyme preferably requires the preferred substrate to be di- and / or oligosaccharides, preferably maltose (as opposed to larger polysaccharides like starch).

[0125] Preferably, the second amylolytic enzyme is inactivated after hydrolyzing at least a portion of the maltose contained in the first intermediate composition; preferably by means of heating and / or change of the pH-value. Methods to inactivate enzymes are known to the skilled person.

[0126] In preferred embodiments, the weight content of the second amylolytic enzyme in the first intermediate composition is within the range of from 0.01 to 4.0 wt.-%; preferably from 0.05 to 3.0 wt.-%, more preferably from 0.1 to 2.5 wt.-%, still more preferably from 0.25 to 2.0 wt.-%, and yet more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total weight of the first intermediate composition.

[0127] In preferred embodiments, the total weight content of enzyme in the first intermediate composition is within the range of from 0.01 to 4.0 wt.-%; preferably from 0.05 to 3.0 wt.-%, more preferably from 0.1 to 2.5 wt.-%, still more preferably from 0.25 to 2.0 wt.-%, and yet more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total weight of the first intermediate composition.

[0128] In step (c) of the process according to the invention a second intermediate composition comprising or essentially consisting of water, protein, glucose, and optionally starch is provided.

[0129] Preferably, the second intermediate composition is a liquid; preferably a suspension.

[0130] The second intermediate composition according to the invention comprises water. Preferably, the weight content of water in the second intermediate composition is the same or less as the weight content of water in the educt protein composition and / or the first intermediate composition.

[0131] Preferably, the concentration of dry matter, i.e. including protein, glucose, optionally starch and all other dissolved constituents but no water, in the second intermediate composition is within the range of from 55 to 95 wt.-%, based on the total weight of the second intermediate composition. In preferred embodiments, said concentration is within the range of from 65 to 92.5 wt.-%, preferably from 70 to 90wt.-%, and more preferably from 75 to 85 wt.-%, in each case based on the total weight of the second intermediate composition.

[0132] The second intermediate composition according to the invention comprises protein. Preferably, the weight content of protein in the second intermediate composition is the same or more as the weight content of protein in the educt protein composition and / or the first intermediate composition.

[0133] The second intermediate composition according to the invention optionally comprises starch. Preferably, the weight content of starch in the second intermediate composition is the same or less as the weight content of starch in the first intermediate composition.

[0134] In preferred embodiments, the relative weight ratio of protein to starch in the second intermediate composition is within the range of from 2.0 : 1.0 to 25 : 1.0, preferably from 3.0 : 1.0 to 23 : 1.0, more preferably from 4.0 : 1.0 to 21 : 1.0, still more preferably from 5.0 : 1.0 to 19 : 1.0, yet more preferably from 6.0 : 1.0 to 17 : 1.0, and even more preferably from 7.0 : 1.0 to 15 : 1.0.

[0135] The second intermediate composition according to the invention comprises glucose.

[0136] In preferred embodiments, the weight content of glucose in the second intermediate composition is at least 0.5 wt.-%; preferably at least 0.75 wt.-%, more preferably at least 1.0 wt.-%, still more preferably at least 1.5 wt.-%, yet more preferably at least 2.0 wt.-%, even more preferably at least 2.5 wt.-%, most preferably at least 3.0 wt.-%, and in particular at least 3.5 wt.-%; in each case relative to the total content of dry matter that is contained in the second intermediate composition.

[0137] In preferred embodiments, the weight content of glucose in the second intermediate composition is at most 8.0 wt.-%; preferably at most 7.5 wt.-%, more preferably at most 7.0 wt.-%, still more preferably at most 6.5 wt.-%, yet more preferably at most 6.0 wt.-%, even more preferably at most 5.5 wt.-%, most preferably at most 5.0 wt.-%, and in particular at most 4.5 wt.-%; in each case relative to the total content of dry matter that is contained in the second intermediate composition.

[0138] In preferred embodiments, the weight content of glucose in the second intermediate composition is within the range of from 1.0 to 7.0 wt.-%; preferably from 1.5 to 6.5 wt.-%, more preferably from 2.0 to 6.0 wt.-%, still more preferably from 2.5 to 5.5 wt.-%, yet more preferably from 3.0 to 5.0 wt.-%, even more preferably from 3.5 to 4.5 wt.-%; in each case relative to the total content of dry matter that is contained in the second intermediate composition.

[0139] Preferably, the weight content of glucose in the second intermediate composition is increased compared to the weight content of glucose in the first intermediate composition.

[0140] In preferred embodiments, the weight content of maltose in the second intermediate composition is at most 2.0 wt.-%; preferably at most 1.0 wt.-%, more preferably at most 0.5 wt.-%, still more preferably at most 0.1 wt.-%, yet more preferably at most 0.05 wt.-%, even more preferably at most 0.01wt.-%, most preferably at most 0.005 wt.-%, and in particular at most 0.001 wt.-%; in each case relative to the total content of dry matter that is contained in the second intermediate composition.

[0141] Preferably, the weight content of maltose in the second intermediate composition is reduced compared to the weight content of maltose in the first intermediate composition.

[0142] The second intermediate composition according to the invention preferably comprises or essentially consists of- 5.0 to 35 wt.-% water; preferably 15 to 25 wt.-%, relative to the total weight of the first intermediate composition;- 60 to 85 wt.-% protein; preferably 70 to 75 wt.-%;- optionally, 1.0 to 15 wt.-% starch; preferably 5.0 to 10 wt.-%- 2.0 to 6.0 wt.-% glucose; preferably 3.5 to 4.5 wt.-%; and- optionally 0.01 to 4.0 wt.-% maltose; preferably 0.5 to 1.5 wt.-%;in each case relative to the total content of dry matter that is contained in the second intermediate composition.

[0143] In step (d) of the process according to the invention at least a portion of the glucose contained in the first intermediate composition or the second intermediate composition is oxidized with catalysis by means of a glucose oxidase thereby providing a protein composition comprising or essentially consisting of water, protein, gluconic acid, optionally starch, and optionally glucose . Thus, in step (d) of the process according to the invention the glucose content contained in the first intermediate composition or the second intermediate composition is reduced.

[0144] Preferably, in step (d) of the process according to the invention glucose is oxidized to gluconic acid.

[0145] In preferred embodiments, in step (d) at least 5.0 wt.-% of the glucose contained in the first intermediate composition or the second intermediate composition is oxidized; preferably at least 10 wt.-%, more preferably at least 20 wt.-%, still more preferably at least 30 wt.-%, yet more preferably at least 40 wt.-%, even more preferably at least 50 wt.-%, most preferably at least 60 wt.-%, and in particular at least 70 wt.-%; in each case relative to the total weight of glucose contained in the first intermediate composition or the second intermediate composition.

[0146] In preferred embodiments, step (d) of the process according to the invention is performed at a temperature of at least 0 °C; preferably at least 2.0 °C, more preferably at least 4.0 °C, still more preferably at least 5.0 °C, and yet more preferably at least 6.0 °C.

[0147] In preferred embodiments, step (d) of the process according to the invention is performed at a temperature of at most 14 °C; preferably at most 12 °C, more preferably at most 10 °C, still more preferably at most 9.0 °C, and yet more preferably at most 8.0 °C.

[0148] Preferably, step (d) of the process according to the invention is performed at a temperature within the range of from 0 to 15 °C; preferably from 1.0 to 14 °C, more preferably from 2.0 to 13 °C, still more preferably from 3.0 to 12 °C, yet more preferably from 4.0 to 11 °C, even more preferably from 5.0 to 10 °C.

[0149] In preferred embodiments, step (d) of the process according to the invention is performed at a pH-value of at least 4.0; preferably at least 4.5, more preferably at least 5.0, and still more preferably at least 5.5.

[0150] In preferred embodiments, step (d) of the process according to the invention is performed at a pH-value of at most 7.5; preferably at most 7.0, more preferably at most 6.5, and still more preferably at most 6.0.

[0151] Preferably, step (d) of the process according to the invention is performed at a pH-value within the range of from 4.0 to 7.5; preferably from 4.3 to 7.2, more preferably from 4.6 to 6.9, still more preferably from 4.9 to 6.6, yet more preferably from 5.2 to 6.3, even more preferably from 5.5 to 6.0.

[0152] Preferably, step (d) of the process according to the invention is performed for a duration within the range of from 2.0 to 78 hours; preferably from 4.0 to 72 hours, more preferably from 6.0 to 66 hours, still more preferably from 8.0 to 60 hours, yet more preferably from 10 to 54 hours, even more preferably from 12 to 48 hours.

[0153] Preferably, step (d) of the process according to the invention does require oxygen, in particular the glucose oxidase does require oxygen for its activity.

[0154] Preferably, step (d) of the process according to the invention is performed under oxygen supply.

[0155] Preferably, step (d) of the process according to the invention is performed under presence of a catalase.

[0156] Preferably, step (d) of the process according to the invention comprises the sub-step of (di) adding the glucose oxidase to the first intermediate composition or the second intermediate composition.

[0157] Preferably, only the glucose oxidase is added to the first intermediate composition or the second intermediate composition.

[0158] Preferably, no xylanase, cellulase, or glucanase is added to the first intermediate composition or the second intermediate composition.

[0159] In preferred embodiments, no catalase is added to the first intermediate composition or the second intermediate composition.

[0160] Preferably, no hydrolytic enzyme or enzymatic antioxidant is added to the first intermediate composition or the second intermediate composition.

[0161] Preferably, no cell-wall modifying enzyme (CWME) is added to the first intermediate composition or the second intermediate composition.

[0162] Preferably, no protein-modifying enzyme is added to the first intermediate composition or the second intermediate composition.

[0163] In preferred embodiments, no xylanase, cellulase, or glucanase, preferably no cell-wall modifying enzyme and no protein-modifying enzyme, is added to any of the compositions according to the invention. Thus, preferably, no xylanase, cellulase, or glucanase, preferably no cell-wall modifying enzyme and no protein-modifying enzyme, is contained in any of the compositions according to the invention.

[0164] The glucose oxidase preferably catalyzes the oxidation of glucose to hydrogen peroxide and glucono -gamma-lactone. Preferably, glucono-gamma-lactone spontaneously hydrolyzes to gluconic acid.

[0165] Preferably, the glucose oxidase is inactivated after oxidizing at least a portion of the glucose contained in the first intermediate composition or the second intermediate composition; preferably by means of heating and / or change of the pH-value . Methods to inactivate enzymes are known to the skilled person.

[0166] In preferred embodiments, the weight content of the glucose oxidase in the first intermediate composition or the second intermediate composition is within the range of from 0.01 to 4.0 wt.-%; preferably from 0.05 to 3.0 wt.-%, more preferably from 0.1 to 2.5 wt.-%, still more preferably from 0.25 to 2.0 wt.-%, and yet more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total weight of the first intermediate composition or the second intermediate composition.

[0167] In preferred embodiments, the total weight content of enzyme in the first intermediate composition or the second intermediate composition is within the range of from 0.01 to 4.0 wt.-%; preferably from 0.05 to 3.0 wt.-%, more preferably from 0.1 to 2.5 wt.-%, still more preferably from 0.25 to 2.0 wt.-%, and yet more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total weight of the first intermediate composition or the second intermediate composition.

[0168] In step (d) of the process according to the invention a protein composition comprising or essentially consisting of water, protein, gluconic acid, optionally starch, and optionally glucose is provided. It is contemplated that the protein composition may comprise residual amounts of maltose.

[0169] Preferably, the protein composition is a liquid; preferably a suspension.

[0170] The protein composition according to the invention comprises water. Preferably, the weight content of water in the protein composition is the same or less as the weight content of water in the educt protein composition and / or the first intermediate composition and / or the second intermediate composition.

[0171] Preferably, the concentration of dry matter, i.e. including protein, gluconic acid, optionally starch, optionally glucose and all other dissolved constituents but no water, in the protein composition is within the range of from 55 to 95 wt.-%, based on the total weight of the protein composition. In preferred embodiments, said concentration is within the range of from 65 to 92.5 wt.-%, preferably from 70 to 90 wt.-%, and more preferably from 75 to 85 wt.-%, in each case based on the total weight of the protein composition.

[0172] The protein composition according to the invention comprises protein. Preferably, the weight content of protein in the protein composition is the same or more as the weight content of protein in the educt protein composition and / or the first intermediate composition and / or the second intermediate composition.

[0173] The protein composition according to the invention optionally comprises starch. Preferably, the weight content of starch in the protein composition is the same or less as the weight content of starch in the first intermediate composition and / or the second intermediate composition.

[0174] In preferred embodiments, the weight content of starch in the protein composition is at most 10 wt.-%; preferably at most 8.0 wt.-%, more preferably at most 6.0 wt.-%, still more preferably at most 5.0 wt.-%, yet more preferably at most 4.0 wt.-%, even more preferably at most 3.0 wt.-%, most preferably at most 2.0 wt.-%, and in particular at most 1.0 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

[0175] In preferred embodiments, the weight content of starch in the protein composition is at most 10 wt.-%; preferably at most 5.0 wt.-%; preferably at most 4.0 wt.-%, more preferably at most 3.5 wt.-%, still more preferably at most 3.0 wt.-%, yet more preferably at most 2.5 wt.-%, even more preferably at most 2.0 wt.-%, most preferably at most 1.5 wt.-%, and in particular at most 1.0 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

[0176] In preferred embodiments, the relative weight ratio of protein to starch in the protein composition is within the range of from 2.0 : 1.0 to 25 : 1.0, preferably from 3.0 : 1.0 to 23 : 1.0, more preferably from 4.0 : 1.0 to 21 : 1.0, still more preferably from 5.0 : 1.0 to 19 : 1.0, yet more preferably from 6.0 : 1.0 to 17 : 1.0, and even more preferably from 7.0 : 1.0 to 15 : 1.0.

[0177] The protein composition according to the invention optionally comprises maltose. Preferably, the weight content of maltose in the protein composition is the same or less as the weight content of maltose in the second intermediate composition.

[0178] The protein composition according to the invention comprises glucose.

[0179] In preferred embodiments, the weight content of glucose in the protein composition is at least 0.1 wt.-%; preferably at least 0.4 wt.-%, more preferably at least 0.7 wt.-%, still more preferably at least 1.0 wt.-%, yet more preferably at least 1.5 wt.-%, even more preferably at least 2.0 wt.-%, most preferably at least 2.5 wt.-%, and in particular at least 3.0 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

[0180] In preferred embodiments, the weight content of glucose in the protein composition is at most 4.5 wt.-%; preferably at most 3.5 wt.-%, more preferably at most 3.0 wt.-%, still more preferably at most 2.5 wt.-%, yet more preferably at most 2.0 wt.-%, even more preferably at most 1.5 wt.-%, most preferably at most 1.0 wt.-%, and in particular at most 0.5 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

[0181] In preferred embodiments, the weight content of glucose in the protein composition is within the range of from 0.1 to 7.0 wt.-%; preferably from 0.3 to 6.5 wt.-%, more preferably from 0.5 to 6.0 wt.-%, still more preferably from 1.0 to 5.5 wt.-%, yet more preferably from 1.5 to 5.0 wt.-%, even more preferably from 2.0 to 4.5 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

[0182] Preferably, the weight content of glucose in the protein composition is reduced compared to the weight content of glucose in the first intermediate composition and / or the second intermediate composition.

[0183] The protein composition according to the invention comprises gluconic acid.

[0184] In preferred embodiments, the weight content of gluconic acid in the protein composition is at least 0.1 wt.-%; preferably at least 0.2 wt.-%, more preferably at least 0.4 wt.-%, still more preferably at least 0.6 wt.-%, yet more preferably at least 0.7 wt.-%, even more preferably at least 0.8 wt.-%, most preferably at least 0.9 wt.-%, and in particular at least 1.0 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

[0185] In preferred embodiments, the weight content of gluconic acid in the protein composition is at most 5.0 wt.-%; preferably at most 4.5 wt.-%, more preferably at most 4.0 wt.-%, still more preferably at most 3.5 wt.-%, yet more preferably at most 3.0 wt.-%, even more preferably at most 2.5 wt.-%, most preferably at most 2.0 wt.-%, and in particular at most 1.5 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

[0186] In preferred embodiments, the weight content of gluconic acid in the protein composition is within the range of from 0.1 to 5.0 wt.-%; preferably from 0.2 to 4.0 wt.-%, more preferably from 0.3 to 3.0 wt.-%, still more preferably from 0.4 to 2.5 wt.-%, yet more preferably from 0.5 to 2.0 wt.-%, even more preferably from 0.75 to 1.5 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

[0187] Preferably, the content of gluconic acid is measured based on the change of pH / oxygen consumption, preferably by HPLC.

[0188] The protein composition according to the invention preferably comprises or essentially consists of- 5.0 to 35 wt.-% water; preferably 15 to 25 wt.-%, relative to the total weight of the protein composition;- 60 to 85 wt.-% protein; preferably 70 to 75 wt.-%;- optionally, 1.0 to 15 wt.-% starch; preferably 5.0 to 10 wt.-%- optionally, 1.0 to 4.5 wt.-% glucose; preferably 1.5 to 4.0 wt.-%; and- optionally 0.01 to 4.0 wt.-% maltose; preferably 0.5 to 1.5 wt.-%;- 0.1 to 5.0 wt.-% gluconic acid; preferably 0.5 to 1.5 wt.-%;in each case relative to the total content of dry matter that is contained in the protein composition.

[0189] Preferably, step (d) of the process according to the invention comprises the sub-steps of (d2) providing a third intermediate composition comprising or essentially consisting of water, protein, glucono-gamma-lactone, optionally starch, and optionally glucose; and(ds) hydrolyzing at least a portion of the glucono-gamma-lactone contained in the third intermediate composition, thereby providing the protein composition.

[0190] The third intermediate composition according to the invention comprises water. Preferably, the weight content of water in the third intermediate composition is the same or less as the weight content of water in the educt protein composition and / or the first intermediate composition and / or the second intermediate composition and / or the protein composition.

[0191] The third intermediate composition according to the invention comprises protein. Preferably, the weight content of protein in the third intermediate composition is the same or more as the weight content of protein in the educt protein composition and / or the first intermediate composition and / or the second intermediate composition and / or the protein composition.

[0192] The third intermediate composition according to the invention optionally comprises starch. Preferably, the weight content of starch in the third intermediate composition is the same or less as theweight content of starch in the first intermediate composition and / or the second intermediate composition and / or the protein composition.

[0193] The third intermediate composition according to the invention comprises glucose. Preferably, the weight content of glucose in the third intermediate composition is the same or more as the weight content of glucose in the protein composition.

[0194] The third intermediate composition according to the invention optionally comprises maltose. Preferably, the weight content of maltose in the third intermediate composition is the same or less as the weight content of maltose in the second intermediate composition and / or the protein composition.

[0195] In preferred embodiments, the weight content of glucono-gamma-lactone in the third intermediate composition is within the range of from 0.005 to 3.0 wt.-%; preferably from 0.007 to 2.5 wt.-%, more preferably from 0.01 to 2.0 wt.-%, still more preferably from 0.04 to 1.5 wt.-%, yet more preferably from 0.07 to 1.0 wt.-%, even more preferably from 0.1 to 0.5 wt.-%; in each case relative to the total weight of the third intermediate composition.

[0196] In preferred embodiments of the process according to the invention, the protein composition is concentrated such that the final concentration of the dry matter including protein and gluconic acid in the thus provided concentrated protein composition is suitable for subsequent processing such as extrusion, preferably for dry extrusion. Concentrating of the protein composition is preferably performed by drying of the protein composition. Suitable drying methods are known to the skilled person. Preferably, the concentration of dry matter, i.e. including protein, gluconic acid, optionally starch, optionally glucose and all other dissolved constituents but no water, in the thus provided concentrated protein composition is within the range of from 70 to 95 wt.-%, based on the total weight of the concentrated protein composition.

[0197] Another aspect of the invention relates to a protein composition obtainable by the process according to the invention as described above.

[0198] Another aspect of the invention relates to a protein composition comprising or essentially consisting of- 5.0 to 35 wt.-% water; preferably 15 to 25 wt.-%, relative to the total weight of the protein composition;- 60 to 85 wt.-% protein; preferably 70 to 75 wt.-%;- optionally, 1.0 to 4.5 wt.-% glucose; preferably 1.5 to 4.0 wt.-%; and- 0.1 to 5.0 wt.-% gluconic acid; preferably 0.5 to 1.5 wt.-%;in each case relative to the total content of dry matter that is contained in the protein composition.

[0199] Another aspect of the invention relates to a process for the preparation of a protein extrudate comprising the step of extruding a protein composition according to the invention as described above.

[0200] Another aspect of the invention relates to a protein extrudate obtainable by the process according to the invention as described above.

[0201] Another aspect of the invention relates to a use of a protein composition according to the invention as described above as starting material for preparing a protein extrudate.

Claims

Patent claims:

1. A process for the preparation of a protein composition comprising the steps of:(a) providing an educt protein composition comprising or essentially consisting of water, protein and starch;(b) hydrolyzing at least a portion of the starch contained in the educt protein composition with catalysis by means of a first amylolytic enzyme, thereby providing a first intermediate composition comprising or essentially consisting of water, protein, glucose, optionally starch, and optionally maltose;(c) optionally, hydrolyzing at least a portion of the maltose contained in the first intermediate composition with catalysis by means of a second amylolytic enzyme, thereby providing a second intermediate composition comprising or essentially consisting of water, protein, glucose, and optionally starch; and(d) oxidizing at least a portion of the glucose contained in the first intermediate composition or the second intermediate composition with catalysis by means of a glucose oxidase thereby providing a protein composition comprising or essentially consisting of water, protein, gluconic acid, optionally starch, and optionally glucose.

2. The process according to claim 1, which is an enzymatic process.

3. The process according to claim 1 or 2, wherein step (a) comprises the sub-steps of(ai) providing a protein source;(a2) optionally, grinding, milling or concentrating the protein source; and(as) mixing the optionally grinded, milled or concentrated protein source with water thereby providing the educt protein composition.

4. The process according to claim 3, wherein the protein contained in the educt protein composition is provided by the protein source; preferably wherein the protein is selected from plant fruits, plant seeds, plant flour, plant protein concentrate, plant protein isolate, and mixtures thereof; preferably plant flour or plant protein concentrate.

5. The process according to claim 4, wherein the plant of the protein source is selected from legumes, cereals, nuts, fungi, algae, and mixtures thereof; preferably from legumes, cereals, nuts, and mixtures thereof; more preferably from beans, preferably soybeans, mung beans, cowpeas or faba beans, peas, chickpeas, lupines, lentils, peanuts, almonds, brazil nuts, cashews, chestnuts,hazelnuts, pecans, pine nuts, walnuts, rice, wheat, rye, oats, barley, millet, maize, and mixtures thereof.

6. The process according to claim 4 or 5, wherein the plant of the protein source is legumes;preferably pulses; more preferably selected from beans, preferably soybeans, mung beans, cowpeas or faba beans, peas, chickpeas, lupines, lentils, peanuts, and mixtures thereof; more preferably faba beans, peas, lentils, and mixtures thereof.

7. The process according to any of claims 3 to 6, wherein the protein source is faba bean flour or faba bean concentrate.

8. The process according to any of the preceding claims, wherein the educt protein composition is a liquid; preferably a suspension.

9. The process according to any of the preceding claims, wherein the weight content of water in the educt protein composition is at least 10 wt.-%; preferably at least 12.5 wt.-%, more preferably at least 15 wt.-%, still more preferably at least 17.5 wt.-%, yet more preferably at least 20 wt.-%, even more preferably at least 22.5 wt.-%, most preferably at least 25 wt.-%, and in particular at least 30 wt.-%; in each case relative to the total weight of the educt protein composition.

10. The process according to any of the preceding claims, wherein the weight content of water in the educt protein composition is at most 40 wt.-%; preferably at most 35 wt.-%, more preferably at most 30 wt.-%, still more preferably at most 27 wt.-%, yet more preferably at most 24 wt.-%, even more preferably at most 21 wt.-%, most preferably at most 18 wt.-%, and in particular at most 15 wt.-%; in each case relative to the total weight of the educt protein composition.

11. The process according to any of the preceding claims, wherein the weight content of water in the educt protein composition is within the range of from 5.0 to 45 wt.-%; preferably from 7.5 to 40 wt.-%, more preferably from 10 to 35 wt.-%, still more preferably from 12.5 to 30 wt.-%, and yet more preferably from 15 to 25 wt.-%; in each case relative to the total weight of the educt protein composition.

12. The process according to any of the preceding claims, wherein the protein is plant protein;preferably selected from leguminous protein, cereal protein, nut protein, fungi protein, algae protein, and mixtures thereof; preferably leguminous protein, cereal protein, nut protein, and mixtures thereof.

13. The process according to any of the preceding claims, wherein the protein is leguminous protein; preferably pulse protein; more preferably selected from bean protein, preferably soybean protein, mung bean protein, cowpea protein or faba bean protein, pea protein, chickpea protein, lupine protein, lentil protein, peanut protein, and mixtures thereof; more preferably faba bean protein, pea protein, lentil protein and mixtures thereof.

14. The process according to any of the preceding claims, wherein the weight content of protein in the educt protein composition is at least 30 wt.-%; preferably at least 35 wt.-%, more preferably at least 40 wt.-%, still more preferably at least 45 wt.-%, yet more preferably at least 50 wt.-%, even more preferably at least 55 wt.-%, most preferably at least 60 wt.-%, and in particular at least 65 wt.-%; in each case relative to the total content of dry matter that is contained in the educt protein composition.

15. The process according to any of the preceding claims, wherein the weight content of protein in the educt protein composition is at most 86 wt.-%; preferably at most 83 wt.-%, more preferably at most 80 wt.-%, still more preferably at most 77 wt.-%, yet more preferably at most 74 wt.-%, even more preferably at most 71 wt.-%, most preferably at most 68 wt.-%, and in particular at most 65 wt.-%; in each case relative to the total content of dry matter that is contained in the educt protein composition.

16. The process according to any of the preceding claims, wherein the weight content of protein in the educt protein composition is within the range of from 35 to 90 wt.-%; preferably from 40 to 85 wt.-%, more preferably from 45 to 80 wt.-%, still more preferably from 50 to 75 wt.-%, yet more preferably from 55 to 70 wt.-%, even more preferably from 60 to 65 wt.-%; in each case relative to the total content of dry matter that is contained in the educt protein composition.

17. The process according to any of the preceding claims, wherein the weight content of starch in the educt protein composition is at least 1.0 wt.-%; preferably at least 3.0 wt.-%, more preferably at least 5.0 wt.-%, still more preferably at least 7.0 wt.-%, yet more preferably at least 9.0 wt.-%, even more preferably at least 11 wt.-%, most preferably at least 13 wt.-%, and in particular at least 15 wt. -%; in each case relative to the total content of dry matter that is contained in the educt protein composition.

18. The process according to any of the preceding claims, wherein the weight content of starch in the educt protein composition is at most 55 wt.-%; preferably at most 50 wt.-%, more preferably at most 45 wt.-%, still more preferably at most 40 wt.-%, yet more preferably at most 35 wt.-%, even more preferably at most 30 wt.-%, most preferably at most 25 wt.-%, and in particular atmost 20 wt.-%; in each case relative to the total content of dry matter that is contained in the educt protein composition.

19. The process according to any of the preceding claims, wherein the weight content of starch in the educt protein composition is within the range of from 1.0 to 35 wt.-%; preferably from 3.0 to 32 wt.-%, more preferably from 6.0 to 29 wt.-%, still more preferably from 9.0 to 26 wt.-%, yet more preferably from 12 to 23 wt.-%, even more preferably from 15 to 20 wt.-%; in each case relative to the total content of dry matter that is contained in the educt protein composition.

20. The process according to any of the preceding claims, wherein in step (b) at least 5.0 wt.-% of the starch contained in the educt protein composition is hydrolyzed; preferably at least 10 wt.-%, more preferably at least 15 wt.-%, still more preferably at least 20 wt.-%, yet more preferably at least 25 wt.-%, even more preferably at least 30 wt.-%, most preferably at least 35 wt.-%, and in particular at least 40 wt.-%; in each case relative to the total weight of starch contained in the educt protein composition.

21. The process according to any of the preceding claims, wherein step (b) is performed at a temperature within the range of from 25 to 85 °C; preferably from 30 to 82 °C, more preferably from 35 to 79 °C, still more preferably from 40 to 76 °C, yet more preferably from 45 to 73 °C, even more preferably from 50 to 70 °C.

22. The process according to any of the preceding claims, wherein step (b) is performed at a pH-value within the range of from 2.5 to 6.5; preferably from 2.8 to 6.2, more preferably from 3.1 to 5.9, still more preferably from 3.4 to 5.6, yet more preferably from 3.7 to 5.3, even more preferably from 4.0 to 5.0.

23. The process according to any of the preceding claims, wherein step (b) is performed for a duration within the range of from 10 to 170 minutes; preferably from 20 to 160 minutes, more preferably from 30 to 150 minutes, still more preferably from 40 to 140 minutes, yet more preferably from 50 to 130 minutes, even more preferably from 60 to 120 minutes.

24. The process according to any of the preceding claims, wherein step (b) comprises the sub -step of (bi) adding the first amylolytic enzyme to the educt protein composition;preferably wherein only the first amylolytic enzyme is added to the educt protein composition; more preferably no xylanase, cellulase, glucanase, or catalase is added to the educt protein composition;still more preferably no further hydrolytic enzyme or enzymatic antioxidant is added to the educt protein composition;yet more preferably, no cell-wall modifying enzyme (CWME) or protein-modifying enzyme is added to the educt protein composition.

25. The process according to any of the preceding claims, wherein the first amylolytic enzyme is selected from amyloglucosidase, alpha-amylase, beta-amylase, gamma-amylase, isoamylase, pullulanase, and amylopullulanase; preferably alpha-amylase or amyloglucosidase; more preferably alpha-amylase.

26. The process according to any of the preceding claims, wherein the weight content of the first amylolytic enzyme in the educt protein composition is within the range of from 0.01 to 4.0 wt.- %; preferably from 0.05 to 3.0 wt.-%, more preferably from 0.1 to 2.5 wt.-%, still more preferably from 0.25 to 2.0 wt.-%, and yet more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total weight of the educt protein composition.

27. The process according to any of the preceding claims, wherein the total weight content of enzyme in the educt protein composition is within the range of from 0.01 to 4.0 wt.-%; preferably from 0.05 to 3.0 wt.-%, more preferably from 0.1 to 2.5 wt.-%, still more preferably from 0.25 to 2.0 wt.-%, and yet more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total weight of the educt protein composition.

28. The process according to any of the preceding claims, wherein the first intermediate composition is a liquid; preferably a suspension.

29. The process according to any of the preceding claims, wherein the weight content of water in the first intermediate composition is the same or less as the weight content of water in the educt protein composition.

30. The process according to any of the preceding claims, wherein the weight content of protein in the first intermediate composition is the same or more as the weight content of protein in the educt protein composition.

31. The process according to any of the preceding claims, wherein the weight content of starch in the first intermediate composition is at least 1.0 wt.-%; preferably at least 1.5 wt.-%, more preferably at least 2.0 wt.-%, still more preferably at least 2.5 wt.-%, yet more preferably at least 3.0 wt.-%, even more preferably at least 3.5 wt.-%, most preferably at least 4.0 wt.-%, and in particular atleast 5.0 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

32. The process according to any of the preceding claims, wherein the weight content of starch in the first intermediate composition is at most 45 wt.-%; preferably at most 40 wt.-%, more preferably at most 35 wt.-%, still more preferably at most 30 wt.-%, yet more preferably at most 25 wt.-%, even more preferably at most 20 wt.-%, most preferably at most 15 wt.-%, and in particular at most 10 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

33. The process according to any of the preceding claims, wherein the weight content of starch in the first intermediate composition is within the range of from 0.5 to 25 wt.-%; preferably from 1.0 to 22 wt.-%, more preferably from 2.0 to 19 wt.-%, still more preferably from 3.0 to 16 wt.-%, yet more preferably from 4.0 to 13 wt.-%, even more preferably from 5.0 to 10 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

34. The process according to any of the preceding claims, wherein the weight content of starch in the first intermediate composition is reduced compared to the weight content of starch in the educt protein composition.

35. The process according to any of the preceding claims, wherein the weight content of glucose in the first intermediate composition is at least 0.5 wt.-%; preferably at least 0.75 wt.-%, more preferably at least 1.0 wt.-%, still more preferably at least 1.5 wt.-%, yet more preferably at least 2.0 wt.-%, even more preferably at least 2.5 wt.-%, most preferably at least 3.0 wt.-%, and in particular at least 3.5 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

36. The process according to any of the preceding claims, wherein the weight content of glucose in the first intermediate composition is at most 8.0 wt.-%; preferably at most 7.5 wt.-%, more preferably at most 7.0 wt.-%, still more preferably at most 6.5 wt.-%, yet more preferably at most 6.0 wt.-%, even more preferably at most 5.5 wt.-%, most preferably at most 5.0 wt.-%, and in particular at most 4.5 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

37. The process according to any of the preceding claims, wherein the weight content of glucose in the first intermediate composition is within the range of from 1.0 to 7.0 wt.-%; preferably from 1.5 to 6.5 wt.-%, more preferably from 2.0 to 6.0 wt.-%, still more preferably from 2.5 to 5.5 wt.-%, yet more preferably from 3.0 to 5.0 wt.-%, even more preferably from 3.5 to 4.5 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

38. The process according to any of the preceding claims, wherein the weight content of maltose in the first intermediate composition is within the range of from 0.01 to 4.0 wt.-%; preferably from 0.05 to 3.5 wt.-%, more preferably from 0.1 to 3.0 wt.-%, still more preferably from 0.15 to 2.5 wt.-%, yet more preferably from 0.2 to 2.0 wt.-%, even more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total content of dry matter that is contained in the first intermediate composition.

39. The process according to any of the preceding claims, wherein in step (c) at least 20 wt.-% of the maltose contained in the first intermediate composition is hydrolyzed; preferably at least 25 wt.- %, more preferably at least 30 wt.-%, still more preferably at least 40 wt.-%, yet more preferably at least 50 wt.-%, even more preferably at least 60 wt.-%, most preferably at least 70 wt.-%, and in particular at least 80 wt.-%; in each case relative to the total weight of maltose contained in the first intermediate composition.

40. The process according to any of the preceding claims, wherein step (c) is performed at a temperature within the range of from 10 to 65 °C; preferably from 15 to 60 °C, more preferably from 20 to 55 °C, still more preferably from 25 to 50 °C, yet more preferably from 30 to 45 °C, even more preferably from 35 to 40 °C.

41. The process according to any of the preceding claims, wherein step (c) is performed at a pH-value within the range of from 5.0 to 8.7; preferably from 5.3 to 8.4, more preferably from 5.6 to 8.1, still more preferably from 5.9 to 7.8, yet more preferably from 6.2 to 7.5, even more preferably from 6.5 to 7.2.

42. The process according to any of the preceding claims, wherein step (c) is performed for a duration within the range of from 10 to 150 minutes; preferably from 15 to 140 minutes, more preferably from 20 to 130 minutes, still more preferably from 25 to 120 minutes, yet more preferably from 30 to 110 minutes, even more preferably from 40 to 100 minutes.

43. The process according to any of the preceding claims, wherein step (c) comprises the sub-step of (ci) adding the second amylolytic enzyme to the first intermediate composition;preferably wherein only the first amylolytic enzyme is added to the first intermediate composition;more preferably no xylanase, cellulase, glucanase, or catalase is added to the first intermediate composition;still more preferably no further hydrolytic enzyme or enzymatic antioxidant is added to the first intermediate composition;yet more preferably, no cell-wall modifying enzyme (CWME) or protein-modifying enzyme is added to the first intermediate composition.

44. The process according to any of the preceding claims, wherein the second amylolytic enzyme is selected from glucosidases or maltose binding protein; preferably alpha-glucosidase, betaglucosidase and maltose binding protein; more preferably alpha-glucosidase; still more preferably maltase -glucoamylase, acid alpha-glucosidase, and neutral alpha-glucosidase C; yet more preferably maltase -glucoamylase.

45. The process according to any of the preceding claims, wherein the weight content of the second amylolytic enzyme in the first intermediate composition is within the range of from 0.01 to 4.0 wt.-%; preferably from 0.05 to 3.0 wt.-%, more preferably from 0.1 to 2.5 wt.-%, still more preferably from 0.25 to 2.0 wt.-%, and yet more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total weight of the first intermediate composition.

46. The process according to any of the preceding claims, wherein the total weight content of enzyme in the first intermediate composition is within the range of from 0.01 to 4.0 wt.-%; preferably from 0.05 to 3.0 wt.-%, more preferably from 0.1 to 2.5 wt.-%, still more preferably from 0.25 to 2.0 wt.-%, and yet more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total weight of the first intermediate composition.

47. The process according to any of the preceding claims, wherein the second intermediate composition is a liquid; preferably a suspension.

48. The process according to any of the preceding claims, wherein the weight content of water in the second intermediate composition is the same or less as the weight content of water in the educt protein composition and / or the first intermediate composition.

49. The process according to any of the preceding claims, wherein the weight content of protein in the second intermediate composition is the same or more as the weight content of protein in the educt protein composition and / or the first intermediate composition.

50. The process according to any of the preceding claims, wherein the weight content of starch in the second intermediate composition is the same or less as the weight content of starch in the first intermediate composition.

51. The process according to any of the preceding claims, wherein the weight content of glucose in the second intermediate composition is at least 0.5 wt.-%; preferably at least 0.75 wt.-%, more preferably at least 1.0 wt.-%, still more preferably at least 1.5 wt.-%, yet more preferably at least 2.0 wt.-%, even more preferably at least 2.5 wt.-%, most preferably at least 3.0 wt.-%, and in particular at least 3.5 wt.-%; in each case relative to the total content of dry matter that is contained in the second intermediate composition.

52. The process according to any of the preceding claims, wherein the weight content of glucose in the second intermediate composition is at most 8.0 wt.-%; preferably at most 7.5 wt.-%, more preferably at most 7.0 wt.-%, still more preferably at most 6.5 wt.-%, yet more preferably at most 6.0 wt.-%, even more preferably at most 5.5 wt.-%, most preferably at most 5.0 wt.-%, and in particular at most 4.5 wt.-%; in each case relative to the total content of dry matter that is contained in the second intermediate composition.

53. The process according to any of the preceding claims, wherein the weight content of glucose in the second intermediate composition is within the range of from 1.0 to 7.0 wt.-%; preferably from 1.5 to 6.5 wt.-%, more preferably from 2.0 to 6.0 wt.-%, still more preferably from 2.5 to 5.5 wt.- %, yet more preferably from 3.0 to 5.0 wt.-%, even more preferably from 3.5 to 4.5 wt.-%; in each case relative to the total content of dry matter that is contained in the second intermediate composition.

54. The process according to any of the preceding claims, wherein the weight content of glucose in the second intermediate composition is increased compared to the weight content of glucose in the first intermediate composition.

55. The process according to any of the preceding claims, wherein the weight content of maltose in the second intermediate composition is at most 2.0 wt.-%; preferably at most 1.0 wt.-%, more preferably at most 0.5 wt.-%, still more preferably at most 0.1 wt.-%, yet more preferably at most 0.05 wt.-%, even more preferably at most 0.01 wt.-%, most preferably at most 0.005 wt.-%, and in particular at most 0.001 wt.-%; in each case relative to the total content of dry matter that is contained in the second intermediate composition.

56. The process according to any of the preceding claims, wherein the weight content of maltose in the second intermediate composition is reduced compared to the weight content of maltose in the first intermediate composition.

57. The process according to any of the preceding claims, wherein in step (d) at least 5.0 wt.-% of the glucose contained in the first intermediate composition or the second intermediate composition is oxidized; preferably at least 10 wt.-%, more preferably at least 20 wt.-%, still more preferably at least 30 wt.-%, yet more preferably at least 40 wt.-%, even more preferably at least 50 wt.-%, most preferably at least 60 wt.-%, and in particular at least 70 wt.-%; in each case relative to the total weight of glucose contained in the first intermediate composition or the second intermediate composition.

58. The process according to any of the preceding claims, wherein step (d) is performed at a temperature within the range of from 0 to 15 °C; preferably from 1.0 to 14 °C, more preferably from 2.0 to 13 °C, still more preferably from 3.0 to 12 °C, yet more preferably from 4.0 to 11 °C, even more preferably from 5.0 to 10 °C.

59. The process according to any of the preceding claims, wherein step (d) is performed at a pH-value within the range of from 4.0 to 7.5; preferably from 4.3 to 7.2, more preferably from 4.6 to 6.9, still more preferably from 4.9 to 6.6, yet more preferably from 5.2 to 6.3, even more preferably from 5.5 to 6.0.

60. The process according to any of the preceding claims, wherein step (d) is performed for a duration within the range of from 2.0 to 78 hours; preferably from 4.0 to 72 hours, more preferably from 6.0 to 66 hours, still more preferably from 8.0 to 60 hours, yet more preferably from 10 to 54 hours, even more preferably from 12 to 48 hours.

61. The process according to any of the preceding claims, wherein step (d) is performed under oxygen supply.

62. The process according to any of the preceding claims, wherein step (d) is performed under presence of a catalase.

63. The process according to any of the preceding claims, wherein step (d) comprises the sub -step of (di) adding the glucose oxidase to the first intermediate composition or the second intermediate composition;preferably wherein only the glucose oxidase is added to the first intermediate composition or the second intermediate composition;more preferably no xylanase, cellulase, glucanase, or catalase is added to the first intermediate composition or the second intermediate composition;still more preferably no hydrolytic enzyme or enzymatic antioxidant is added to the first intermediate composition or the second intermediate composition;yet more preferably, no cell-wall modifying enzyme (CWME) or protein-modifying enzyme is added to the first intermediate composition or the second intermediate composition.

64. The process according to any of the preceding claims, wherein the weight content of the glucose oxidase in the first intermediate composition or the second intermediate composition is within the range of from 0.01 to 4.0 wt.-%; preferably from 0.05 to 3.0 wt.-%, more preferably from 0.1 to 2.5 wt.-%, still more preferably from 0.25 to 2.0 wt.-%, and yet more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total weight of the first intermediate composition or the second intermediate composition.

65. The process according to any of the preceding claims, wherein the total weight content of enzyme in the first intermediate composition or the second intermediate composition is within the range of from 0.01 to 4.0 wt.-%; preferably from 0.05 to 3.0 wt.-%, more preferably from 0.1 to 2.5 wt.- %, still more preferably from 0.25 to 2.0 wt.-%, and yet more preferably from 0.5 to 1.5 wt.-%; in each case relative to the total weight of the first intermediate composition or the second intermediate composition.

66. The process according to any of the preceding claims, wherein the protein composition is a liquid;preferably a suspension.

67. The process according to any of the preceding claims, wherein the weight content of water in the protein composition is the same or less as the weight content of water in the educt protein composition and / or the first intermediate composition and / or the second intermediate composition.

68. The process according to any of the preceding claims, wherein the weight content of protein in the protein composition is the same or more as the weight content of protein in the educt protein composition and / or the first intermediate composition and / or the second intermediate composition.

69. The process according to any of the preceding claims, wherein the weight content of starch in the protein composition is the same or less as the weight content of starch in the first intermediate composition and / or the second intermediate composition;preferably wherein the weight content of starch in the protein composition is at most 5.0 wt.-%; preferably at most 4.0 wt.-%, more preferably at most 3.5 wt.-%, still more preferably at most 3.0 wt.-%, yet more preferably at most 2.5 wt.-%, even more preferably at most 2.0 wt.-%, most preferably at most 1.5 wt.-%, and in particular at most 1.0 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

70. The process according to any of the preceding claims, wherein the weight content of maltose in the protein composition is the same or less as the weight content of maltose in the second intermediate composition.

71. The process according to any of the preceding claims, wherein the weight content of glucose in the protein composition is at least 0.1 wt.-%; preferably at least 0.4 wt.-%, more preferably at least 0.7 wt.-%, still more preferably at least 1.0 wt.-%, yet more preferably at least 1.5 wt.-%, even more preferably at least 2.0 wt.-%, most preferably at least 2.5 wt.-%, and in particular at least 3.0 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

72. The process according to any of the preceding claims, wherein the weight content of glucose in the protein composition is at most 4.5 wt.-%; preferably at most 3.5 wt.-%, more preferably at most 3.0 wt.-%, still more preferably at most 2.5 wt.-%, yet more preferably at most 2.0 wt.-%, even more preferably at most 1.5 wt.-%, most preferably at most 1.0 wt.-%, and in particular at most 0.5 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

73. The process according to any of the preceding claims, wherein the weight content of glucose in the protein composition is within the range of from 0.1 to 7.0 wt.-%; preferably from 0.3 to 6.5 wt.-%, more preferably from 0.5 to 5.0 wt.-%, still more preferably from 1.0 to 5.5 wt.-%, yet more preferably from 1.5 to 5.0 wt.-%, even more preferably from 2.0 to 4.5 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

74. The process according to any of the preceding claims, wherein the weight content of glucose in the protein composition is reduced compared to the weight content of glucose in the first intermediate composition and / or the second intermediate composition.

75. The process according to any of the preceding claims, wherein the weight content of gluconic acid in the protein composition is at least 0.1 wt.-%; preferably at least 0.2 wt.-%, more preferably at least 0.4 wt.-%, still more preferably at least 0.6 wt.-%, yet more preferably at least 0.7 wt.-%, even more preferably at least 0.8 wt.-%, most preferably at least 0.9 wt.-%, and in particular at least 1.0 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

76. The process according to any of the preceding claims, wherein the weight content of gluconic acid in the protein composition is at most 5.0 wt.-%; preferably at most 4.5 wt.-%, more preferably at most 4.0 wt.-%, still more preferably at most 3.5 wt.-%, yet more preferably at most 3.0 wt.- %, even more preferably at most 2.5 wt.-%, most preferably at most 2.0 wt.-%, and in particular at most 1.5 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

77. The process according to any of the preceding claims, wherein the weight content of gluconic acid in the protein composition is within the range of from 0.1 to 5.0 wt.-%; preferably from 0.2 to 4.0 wt.-%, more preferably from 0.3 to 3.0 wt.-%, still more preferably from 0.4 to 2.5 wt.-%, yet more preferably from 0.5 to 2.0 wt.-%, even more preferably from 0.75 to 1.5 wt.-%; in each case relative to the total content of dry matter that is contained in the protein composition.

78. The process according to any of the preceding claims, wherein step (d) comprises the sub-steps of(d2) providing a third intermediate composition comprising or essentially consisting of water, protein, optionally starch, optionally glucose and glucono -gamma-lactone; and (ds) hydrolyzing at least a portion of the glucono -gamma-lactone contained in the third intermediate composition, thereby providing the protein composition.

79. A protein composition obtainable by the process according to any of the preceding claims.

80. A protein composition comprising or essentially consisting of- 5.0 to 35 wt.-% water; preferably 15 to 25 wt.-%, relative to the total weight of the protein composition;- 60 to 85 wt.-% protein; preferably 70 to 75 wt.-%;- optionally, 1.0 to 4.5 wt.-% glucose; preferably 1.5 to 4.0 wt.-%; and- 0.1 to 5.0 wt.-% gluconic acid; preferably 0.5 to 1.5 wt.-%;in each case relative to the total content of dry matter that is contained in the protein composition.

81. A process for the preparation of a protein extrudate comprising the step of extruding a protein composition according to any of claims 1 to 80.

82. A protein extrudate obtainable by the process according to claim 81.

83. Use of a protein composition according to any of claims 1 to 80 as starting material for preparing a protein extrudate.