Production method of bean protein

Abstract

The present invention relates to the field of plant protein. In particular, the present invention relates to a method for producing bean protein, preferably pea protein, comprising: dry heat treating bean seeds at a temperature between 70°C and 130°C for 1 minute to 6 minutes, then grinding the seeds into powder and suspending the powder in an aqueous solution, separating soluble components from the suspension and extracting protein from the soluble components. The present invention also relates to a protein composition that can be obtained by the method.

Description

Technical Field

[0001] The present invention relates to the field of plant proteins, and in particular to a method for producing bean protein, preferably pea protein, and a protein composition obtainable by the method. Background Art

[0002] The daily protein requirement of humans accounts for 12% to 20% of the food intake. These proteins are provided by animal products (meat, fish, eggs, dairy products) and plant products (cereals, beans, algae).

[0003] In industrialized countries, people consume mainly animal protein. However, many studies have shown that excessive intake of animal protein, rather than plant protein, is one of the reasons for the increase in cancer and cardiovascular disease.

[0004] Furthermore, animal protein has many drawbacks, both in terms of allergenicity (especially proteins from milk or eggs) and environmental protection (related to the harmful effects of intensive farming).

[0005] Plant-derived compounds do not have the same disadvantages as animal-derived compounds, so the industry's demand for plant-derived compounds with high nutritional value and functional properties is increasing day by day.

[0006] Soybeans have been and still are the most important plant-based alternative to animal protein. However, there are certain disadvantages to using soy. Soybean seeds are often genetically modified and need to be de-oiled using solvents to obtain their protein.

[0007] Seed plants, especially peas, have been developed in Europe (mainly in France) since the 1870s as an alternative protein source to animal proteins for animal and human food. The protein content of peas is about 27% by weight. The term "pea" in its broadest sense specifically includes all wild varieties of "smooth peas" for various uses (human food, animal feed and / or other uses), as well as all mutant varieties of "smooth peas" and "wrinkled peas". These seeds are non-GMO and do not require solvent de-oiling.

[0008] Pea proteins, mainly vicilin, have been industrially extracted and processed for many years. Patent EP1400537 can be cited as an example of a pea protein extraction process. In this process, the seeds are ground without water (the so-called "dry grinding" process) to obtain bean flour. This bean flour is then suspended in water to extract the protein.

[0009] Despite its undeniable qualities, proteins extracted from peas have a so-called "peay", "beany" or "vegetable" taste compared to animal proteins. This taste is an undeniable constraint in many industrial applications, especially in food.

[0010] This is particularly true in the beverage sector, where improved sensory profiles are essential, as it is difficult to mask the taste of protein: the addition of additional ingredients may actually result in changes in the solution stability, viscosity and / or palatability of the beverage. Additionally, it is advantageous for proteins to have weak gelling power or low viscosity, which allows for higher protein content without causing the beverage to gel or become too thick.

[0011] After extensive research, it has been clearly demonstrated that one of the main causes of these unpleasant tastes comes from the synthesis of aldehydes and / or ketones (especially hexanal) due to the action of internal lipoxygenases on residual lipids during protein extraction. The types of compounds that produce these unpleasant tastes also include saponins and 3-alkyl-2-methoxypyrazines ("Flavor aspects of pulse ingredients", Wibke SURoland, 2017).

[0012] Therefore, those skilled in the art have devised several solutions that can improve the taste of commercially available pea proteins and make them tasteless. The first solution is to mask the taste by adding compounds selected for this purpose: this solution requires users to add compounds that they do not want to add to their formulas and may be the source of regulatory and / or allergy problems. Another solution is described in patent US4,022,919, which proposed as early as the 1970s that treating the pea protein with water vapor can obtain proteins with improved taste. However, people criticize that this method may change the functional qualities of the protein obtained by thermal modification (such as loss of solubility or increased hydration capacity) and that necessary purification steps must be added before use. Therefore, these solutions are effective, but they require the end user of the protein to perform additional purification operations, which may change the functionality of the pea protein. Therefore, those skilled in the art are bound to seek to obtain tasteless pea proteins directly and simply during the extraction process.

[0013] Many possible solutions have been explored, including but not limited to selecting pea cultivars with low lipoxygenase content or pre-germinating peas before protein extraction. A recent patent application WO2017 / 120597 can be taken as an example, in which a method is described, including precipitation by adding salt, multiple washings and recovery by centrifugation. Although this is a complex method using a large amount of water (up to 30 times the amount of peas), pea protein still has a "bean taste" and "bitter" (see Figures 18A, B and C of the application WO2017 / 120597).

[0014] Since lipoxygenase and saponin are sensitive to temperature, the document WO 2019 / 053387 considers adding additional heat treatment during the extraction step, including heating in a wet medium (bleaching), optionally combined with a quenching step. Unfortunately, these steps use a lot of water and produce soluble by-products that must be utilized. In addition, it is not possible to produce proteins with low gelling power using this method.

[0015] Similar soybean processing uses "roasting" or dry heating (also called toasting). A major problem for the pea industry is the preservation of pea starch, which should not be degraded so that it still has industrial value. Soybean seeds do not contain starch: therefore, the soybean industry can use very high heating temperatures to inhibit lipoxygenase without worrying about starch.

[0016] Heating the seeds can also lead to changes in protein functionality (such as solubility or emulsifying power), which can hamper certain applications, especially in food.

[0017] It is therefore of interest to obtain pulse proteins, in particular pulse protein isolates, and even more in particular pea protein isolates, with improved flavour, while providing an optimised extraction process and ensuring functionality. DETAILED DESCRIPTION

[0019] The inventors have shown that a preliminary step of heat treatment of the seeds at a temperature between 70°C and 130°C for 1 to 6 minutes, advantageously between 100°C and 120°C for 2 to 4 minutes, inhibits the activity of internal lipoxygenases while preserving the functionality of the starch and guaranteeing the extraction yield of the components. The method developed by the inventors makes it possible to obtain a soy protein composition whose functional properties are particularly suitable for application in protein-rich beverages: improved sensory experience, reduced gelling power and improved emulsifying power.

[0020] According to a first aspect of the present invention, there is provided a method for producing a bean protein composition, comprising the following steps:

[0021] i) dry heat treating pulse seeds, preferably selected from peas, lupins and broad beans, at a temperature of between 70°C and 130°C, such as between 80°C and 125°C, especially between 100°C and 120°C, for 1 minute to 6 minutes, such as 1.5 minutes to 5 minutes, especially 2 minutes to 4 minutes;

[0022] ii) grinding the seeds into powder and suspending the powder in an aqueous solution, preferably, the concentration of dry matter in the suspension is 15% to 25%, more preferably 20%,

[0023] iii) separating the soluble components from the suspension using centrifugal force,

[0024] iv) Extraction of proteins from the soluble fraction.

[0025] In a preferred embodiment, the extraction of proteins from said fraction comprises the steps of coagulating the proteins in the aqueous solution at a pH value between 4 and 6 and heat-treating the solution at a temperature between 45° C. and 65° C., preferably 55° C., in particular for 3.5 minutes to 4.5 minutes, preferably for 4 minutes. Preferably, the coagulated proteins are recovered, preferably by centrifugation, and suspended in an aqueous solution. The pH value of the aqueous coagulated protein solution can then be adjusted to between 6 and 8, preferably 7, and the aqueous suspension can be heat-treated at a temperature between 130° C. and 150° C., preferably 140° C., for 5 seconds to 15 seconds, preferably 10 seconds. The method can also comprise a drying step of the aqueous coagulated protein suspension.

[0026] According to another aspect, a bean protein composition is provided which can be obtained according to the method according to the first aspect of the invention.

[0027] According to the last aspect of the present invention, there is provided a protein composition obtainable by the method according to the first aspect of the present invention, for use in animal or human food industry.

[0028] The present invention can be better understood from the following detailed description.

[0029] BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1

[0031] [ Figure 1 ] shows the viscosity analysis curves of the protein composition obtained by the following method: heat treatment of seeds at 100°C for 4 minutes or at 120°C for 2 minutes, or no heat treatment. DETAILED DESCRIPTION

[0032] According to a first aspect of the present invention, there is provided a method for producing a bean protein composition, comprising the following steps:

[0033] i) dry heating the pulse seeds at a temperature of between 70°C and 130°C, for example between 80°C and 125°C, especially between 100°C and 120°C, for 1 minute to 6 minutes, for example 1.5 minutes to 5 minutes, especially 2 minutes to 4 minutes;

[0034] ii) grinding the seeds into powder and suspending them in an aqueous solution;

[0035] iii) separating the soluble components from the suspension, preferably using centrifugal force;

[0036] iv) Extraction of proteins from the soluble fraction.

[0037] The term "protein composition" is understood in the present application as a composition obtained by extraction and purification, said composition comprising proteins, macromolecules consisting of one or more polypeptide chains, which consist of a number of amino acid residues linked to each other by peptide bonds. In the specific context of pea proteins, the present invention is particularly concerned with globulins (about 50%-60% of pea proteins). Pea globulins are mainly divided into three subfamilies: legumin, tartin and fernin.

[0038] The term "legume" as used herein refers to the order Vicia, a dicotyledonous plant. This plant is an extremely common flowering plant, second only to the orchidaceae and the Asteraceae in number of species. It includes approximately 765 genera and more than 19,500 species. Many legumes are important cultivated plants, including soybeans, beans, peas, chickpeas, broad beans, peanuts, cultivated lentils, cultivated alfalfa, various clover, broad beans, carob, liquorice and lupine.

[0039] According to a preferred embodiment of the present invention, the bean protein is selected from peas, kidney beans, broad beans, broad beans and mixtures thereof, preferably peas.

[0040] The term "pea" specifically includes all wild varieties of "round pea" and all mutant varieties of "round pea" and "wrinkled pea".

[0041] When the selected pulses are peas, the peas may be treated, prior to the heating and grinding steps of the method according to the invention, by steps well known to those skilled in the art, such as, in particular, cleaning (removal of unwanted particles, such as stones, dead insects, soil residues, etc.) and external fiber stripping (also known as "dehulling" in English), at a temperature between 70°C and 130°C, for example between 80°C and 125°C, in particular between 100°C and 120°C, for 1 minute to 6 minutes, for example 1.5 minutes to 5 minutes, in particular 2 minutes to 4 minutes;

[0042] The method according to the invention comprises a step i) which comprises heat-treating the legume seeds at a temperature between 70°C and 130°C, for example between 80°C and 125°C, in particular between 100°C and 120°C, for 1 minute to 6 minutes, for example 1.5 minutes to 5 minutes, in particular 2 minutes to 4 minutes. This heat treatment is a dry heat treatment, that is to say it is carried out in the absence of other aqueous solvents than the solvent present in the seeds. This dry heat treatment or baking differs from microwave treatment in that the heat is provided by convection, which allows precise control of the heat treatment of the seeds (time and temperature). This dry heat treatment is particularly advantageous because it can be easily implemented, for example without the need to control relative humidity. As in the examples shown in the present application, it is important to strictly follow the time intervals and temperatures so as to be able to inhibit the activity of the internal lipoxygenase while retaining the functionality of the starch and ensuring the extraction rate of the various components.

[0043] Following this preliminary step of heat treatment under these specific conditions, and following the conditions of the various steps of the method, it is possible to obtain a soy protein composition whose functional properties are particularly suitable for application in protein-rich beverages: improved organoleptic experience, reduced gelling power and improved emulsifying power.

[0044] In an even more preferred embodiment, the temperature is between 110° C. and 120° C., such as 120° C. This option allows obtaining very low viscosity of the protein composition, which is an additional advantage in certain food applications such as high protein beverages.

[0045] This step can optionally be completed by removing the outer fibers (cellulose husk) of the peas through a well-known step also known as "dehulling".

[0046] The method according to the invention comprises the step ii) grinding the seeds into a powder and suspending them in an aqueous solution.

[0047] Milling is performed by any suitable technique known to the skilled person, such as a ball mill, a cone mill, a spiral mill, an air jet mill or a rotor / rotor system.

[0048] During the milling process, water may be added continuously or discontinuously at the beginning, during or at the end of the milling so as to obtain, at the end of this stage, an aqueous suspension of milled peas having a dry matter (DM) weight of between 15% and 25%, preferably 20% by weight of dry matter, relative to the weight of the suspension.

[0049] At the end of milling, the pH value can be checked. Preferably, at the end of step ii), the pH value of the aqueous suspension of milled peas is adjusted to between 8 and 10, preferably to 9. The pH value can be adjusted by adding an acid and / or a base, such as sodium hydroxide or hydrochloric acid. Preferably, ascorbic acid, citric acid or potassium salts or sodium hydroxide are used.

[0050] The method according to the invention then comprises a step iii) of separating the soluble components from the aqueous suspension, preferably by means of centrifugal force. This step makes it possible to separate the soluble fraction from the insoluble fraction of the suspension. The insoluble fraction consists mainly of starch and polysaccharides known as "internal fiber". The proteins are concentrated in the soluble fraction (supernatant).

[0051] The starch and the fibers can also be separated by carrying out a first sieving step aimed at removing the internal fibers from the peas. This first step is necessary because the internal fibers of the peas are very easily bound to the starch and proteins of the peas. These fibers must then be washed several times to extract the starch or the associated proteins. After this sieving step, the suspension free of the internal fibers is centrifuged to generate a "light phase" containing mainly proteins and a "heavy phase" containing mainly starch.

[0052] The method according to the invention comprises a step iv) of extracting the protein from the soluble fraction. The extraction can be carried out by any type of suitable method, such as protein precipitation at isoelectric pH or thermal coagulation by heating.

[0053] Preferably, the extraction of the protein comprises the steps of coagulating the protein in an aqueous solution at a pH between 4 and 6, preferably 5, followed by heating at a temperature between 45°C and 65°C, preferably 55°C.

[0054] The contact time may be between 1 minute and 30 minutes, for example between 1 minute and 10 minutes, preferably between 3 minutes and 5 minutes, even more preferably 5 minutes. Here, the aim is to separate the key pea proteins from the other components of the supernatant in step iv). Correct control of the time / temperature schedule is crucial.

[0055] Preferably, heating is performed by indirect injection of steam, for example by injecting steam into the jacket of a tank equipped with a stirrer.

[0056] The coagulated protein, also called coagulated protein floc, can then be recovered by centrifugation. The solid part of the concentrated protein is separated from the liquid part of the concentrated sugar and salt. The floc is then suspended in an aqueous solution, preferably an aqueous solution diluted with water. The dry matter weight relative to the suspension is adjusted to between 10% and 20%, preferably 15%.

[0057] The pH of the protein flocs can then be adjusted to between 6 and 8, preferably 7. Any acidic and alkaline agents are used to adjust the pH. Ascorbic acid, citric acid or potassium salts or sodium hydroxide are preferably used.

[0058] A heat treatment may then be performed at a temperature between 130° C. and 150° C., preferably 140° C., for 5 seconds to 15 seconds, preferably 10 seconds.

[0059] Protein extraction can be preferably performed by drying using any technique known to the skilled person. Preferably, the coagulated protein flocs are dried to a weight percentage of more than 80%, preferably more than 90%, relative to the dry matter. For this purpose, any technique known to the skilled person can be used, such as freeze drying or atomization. Atomization is a preferred technique, in particular multi-effect atomization.

[0060] The dry matter content is measured by any method known to a person skilled in the art, preferably using the so-called "drying" method. It consists in determining the amount of evaporated water by heating a known amount of a sample of known mass: initially the sample is weighed and the mass m1 is measured in g; the sample is placed in a heating chamber to evaporate the water until the mass of the sample is stable and the water is completely evaporated (preferably at a temperature of 105°C at atmospheric pressure), and finally the sample is weighed and the mass m2 is measured in g. The dry matter is obtained by the following calculation: (m2 / m1)*100.

[0061] According to a second aspect of the present invention, there is thus provided a pulse protein composition obtainable by the method according to the first aspect of the invention, wherein the pulses are in particular selected from peas, lupins and beans.

[0062] Preferably, the protein richness of the pulse protein composition according to the invention is more than 80%, preferably more than 85%, more preferably more than 90% by total weight of dry matter.

[0063] Protein abundance is measured by any technique known to those skilled in the art. Preferably, the total nitrogen content (calculated as a percentage of the weight of nitrogen to the total dry weight of the composition) is measured and the result is multiplied by a factor of 6.25. This method is well known in the field of vegetable proteins and is based on the fact that proteins contain an average of 16% nitrogen. Any dry matter determination method known to those skilled in the art may also be used.

[0064] As shown in the examples below, the protein composition according to the invention is novel because its organoleptic characteristics, specifically the "vegetable" or "bean" component, are improved. This component is usually evaluated by a sensory taste panel. This difference can also be characterized by analyzing volatile compounds using a gas chromatograph equipped with a mass spectrometer.

[0065] This composition is also characterized by an optimized gelling power, which is reduced by about 2 times compared to a soy protein composition obtained by a production method that does not include a step of heat treatment of the soy seeds.

[0066] "Gelling power" refers to the functional property of a protein composition's ability to form a gel or network while increasing viscosity and producing a state of matter intermediate between a liquid and a solid. The term "gel strength" may also be used. To quantify this gelling power, it is necessary to generate such a network and assess its strength. To perform this quantification, Test A is used in the present invention and is described as follows:

[0067] 1) solubilizing the test protein composition in water containing 15% + / - 2% dry matter at a pH of 7 at 60°C + / - 2°C;

[0068] 2) Stir at 60°C + / - 2°C for 5 minutes;

[0069] 3) Cool to 20°C + / - 2°C and stir at 350 rpm for 24 hours;

[0070] 4) preparing the suspension in a yield stress rheometer equipped with a concentric plunger;

[0071] 5) The following temperature curve is formed:

[0072] a. Stage 1: within 10 minutes, heating from 20℃+ / -2℃ to 80℃+ / -2℃;

[0073] b. Stage 2: Stabilize at 80°C + / - 2°C for 120 minutes;

[0074] c. Stage 3: Cool from 80°C + / - 2°C to 20°C + / - 2°C within 30 minutes;

[0075] 6) Measure the gel strength, unit: Pa.

[0076] Preferably, the yield stress rheometer is a TA Instruments AR 2000 equipped with a Duvet geometry parameter determination instrument and a Peltier effect temperature regulation system. In order to avoid evaporation problems at high temperatures, paraffin oil is added to the sample.

[0077] A "rheometer" in the sense of the present invention is a laboratory instrument capable of measuring the rheological properties of a fluid or gel. It applies forces to a sample. In general, its characteristic dimensions are small (the mechanical inertia of the rotor is low), allowing the mechanical properties of liquids, gels, suspensions, pastes, etc. to be fundamentally studied under the influence of applied forces.

[0078] The so-called "yield stress" mode allows, by applying a sinusoidal stress (oscillatory mode), to determine the intrinsic viscoelastic quantities of the material, which depend inter alia on time (or angular velocity ω) and temperature. Specifically, this type of rheometer makes it possible to obtain the complex modulus G*, which in turn makes it possible to obtain the modulus G' or elastic part and G" or viscous part.

[0079] This composition is also characterized by an optimized emulsifying power, which is reduced by about 2 times compared to a soy protein composition obtained by a production method that does not include a step of heat treatment of the soy seeds.

[0080] "Emulsifying power" or "emulsifying capacity" refers to the maximum amount of oil that can be dispersed into an aqueous solution containing a defined amount of emulsifier before the emulsion breaks or reverses (Sherman, 1995). In order to quantify it, the applicant has developed a test that can easily, quickly and reproducibly quantify it:

[0081] - Disperse 0.2g of product sample into 20mL of water,

[0082] - The solution was homogenized at 9500 rpm for 30 seconds using Ultraturax IKA T25 equipment,

[0083] - Under the same conditions as in step 2 above, add 20 mL of corn oil and homogenize at the same time,

[0084] - Centrifuge at 3100 g for 5 minutes,

[0085] - If a good emulsion is obtained, increase the amount of water and corn by 50% and restart the test from item 1,

[0086] - If a bad emulsion is obtained (phase shift), reduce the amount of water and corn by 50% and restart the test from item 1,

[0087] -Therefore, the maximum emulsifiable oil amount (Qmax, unit: mL) is determined,

[0088] - Therefore, the emulsification capacity is the maximum amount of corn oil that can be emulsified per gram of product,

[0089] -Emulsification capacity = (Qmax / 0.2)*100

[0090] According to a final aspect of the invention, it is proposed to industrially use a legume protein composition, preferably a legume protein isolate selected from pea, lupin and bean, more preferably a pea protein isolate according to the invention, in particular for animal and human food.

[0091] As shown in the examples below, by implementing the method according to the invention, a protein composition is obtained characterized by improved organoleptic properties, at least halved gel strength and at least doubled emulsifying power compared to a bean protein composition obtained without heat treatment of bean seeds. These characteristics are particularly suitable for protein-enriched beverages such as RTD ("Ready To Drink"), plant milk alternatives or reconstituted powdered beverages or "Powder-mixes".

[0092] Improved sensory characteristics are crucial for the end consumer, but a reduction in gelling power would also allow the protein content to be increased without making the beverage too thick. Finally, emulsifying power may also be of interest, for example in order to stabilize essential fatty acids.

[0093] The present invention will be better understood by reference to the following non-limiting examples.

[0094] Example

[0095] Example 1: Effect of heating parameters of legume seeds on protein production process .

[0096] In this example, yellow pea (Pisum savitum) seeds that have been cleaned and freed from external foreign matter such as stones will be used.

[0097] Several heat treatment techniques were used for comparison:

[0098] - Ventilated constant temperature box, 2 minutes to 10 minutes, 80℃ to 120℃

[0099] - Microwave, 30 seconds to 3 minutes, 1000W

[0100] - High pressure steam sterilization, 5 minutes to 15 minutes, 100℃ to 120℃

[0101] The following protein and starch extraction methods were then applied:

[0102] -Separation of outer fibers and pea cotyledons

[0103] - Grinding peas with a stone grinder

[0104] -Suspend the powder in water containing 17% dry matter (DM) at 20°C + / - 2°C and pH 7 + / - 1

[0105] - Stir for 30 minutes

[0106] - Separate the insoluble matter (starch and internal fibers) by centrifugation at 1000G for 5 minutes

[0107] - Distill the supernatant to pH 5

[0108] Heat at -55°C for 20 minutes in a vessel equipped with a jacket and stirrer

[0109] - Recover the protein composition by centrifugation at 5000G for 5 minutes

[0110] - Adjust pH to 7 with 1N NaOH

[0111] - Heat treatment by direct injection at 140°C for 10 seconds

[0112] -Spray drying

[0113] Several measurements were performed to characterize and compare the various methods:

[0114] - The starch modification state was obtained by DSC and thermal enthalpy measurement

[0115] - Calculate protein recovery (Rdt) (extracted protein amount / total protein amount)

[0116] - Taste. This component is usually evaluated by a sensory tasting panel.

[0117] The results are shown in Table 1 below:

[0118] [Table 1]

[0119] sample smell Starch quality Protein recovery Ventilated constant temperature box / 80℃ / 10 minutes to 60 minutes Overdoing it Ok Ok Ventilated constant temperature box / 120℃ / 10 minutes to 60 minutes Overheat+ Ok medium Ventilated constant temperature box / 150℃ / 10 minutes to 60 minutes Overdoing it++ Ok Difference Ventilated constant temperature box / 80℃ / 2 minutes OK Ok Ok Ventilated constant temperature box / 80℃ / 5 minutes OK Ok Ok Ventilated constant temperature box / 120℃ / 2 minutes Ok Ok Ok Ventilated constant temperature box / 120℃ / 5 minutes Ok Ok OK High pressure steam sterilization / 5 minutes / 120℃ pea Ok Ok High pressure steam sterilization / 10 minutes / 110℃ pea Ok OK High pressure steam sterilization / 15 minutes / 100℃ Peas+ Ok OK Microwave / 1 hour 30 minutes Overcooked + / Bitter + OK OK Microwave / 3 minutes Overcooked++ / bitter++ OK OK Microwave / 30 seconds pea OK OK Microwave / 60 seconds Overdoing it OK OK Microwave / 90 seconds Overheat+ OK OK

[0120] Dry heating pretreatment can improve the taste of the resulting protein while retaining the functionality of starch and ensuring the extraction rate of each component.

[0121] Example 2: Example to demonstrate the effect of dry heat treatment on the quality of the resulting protein composition .

[0122] The purpose of this example is to demonstrate the effect of dry heat treatment on the quality of the resulting protein composition.

[0123] - Three types of seed pretreatment were studied:

[0124] a. No pretreatment

[0125] b. Ventilated oven, 100°C for 4 minutes

[0126] c. Ventilated oven, 120℃ for 2 minutes

[0127] -Separation of outer fibers and pea cotyledons

[0128] - Grinding peas with a stone grinder

[0129] -Suspend the powder in water containing 17% dry matter at 20°C + / - 2°C and pH 7 + / - 1

[0130] - Stir for 30 minutes

[0131] - Separate the insoluble matter (starch and internal fibers) by centrifugation at 1000G for 5 minutes

[0132] - Distill the supernatant to pH 5

[0133] Heat at -55°C for 20 minutes in a vessel equipped with a jacket and stirrer

[0134] - Recover the protein composition by centrifugation at 5000G for 5 minutes

[0135] - Adjust pH to 7 with 1N NaOH

[0136] - Heat treatment by direct injection at 140°C for 10 seconds

[0137] -Spray drying.

[0138] Several measurements were performed to characterize and compare the trials:

[0139] - Dry matter content measured by drying.

[0140] - Protein content calculated by measuring the total nitrogen content and multiplying the result by a factor of 6.25

[0141] -Protein recovery (extracted protein amount / total protein amount)

[0142] - Emulsifying activity measured by the test developed by the applicant mentioned above.

[0143] - Gel strength measured by Test A above.

[0144] The results are summarized in Table 2 below:

[0145] [Table 2]

[0146]

[0147] The protein composition according to the present invention has almost doubled emulsifying power and lower gel strength.

[0148] The viscosity of the protein composition was measured using a TA Instruments AR 2000 rheometer equipped with a Duvet geometry and a Peltier temperature control system. The measurement was carried out at a temperature of 20°C and a shear rate of 0.006 to 600 s-1 for 3 minutes.

[0149] The protein composition according to the present invention prepared at a temperature of 120° C. also has a lower viscosity ( Figure 1 ).

[0150] On the other hand, a similar method for the preparation of protein composition a (obtained without pretreatment) is achieved by replacing "grinding peas with a stone mill" with "wet grinding pea cotyledons" as described in Example 1 of document WO2019 / 053387. The grinding involves placing the pea cotyledons in an aqueous solution at 80°C, heat treating for 3 minutes while maintaining the solution at that temperature, then recovering the peas and cooling them to 10°C by immersing them in water adjusted to 7°C, and then grinding the peas into a solution. At the end of the method, a control protein composition is obtained, the gel strength of which does not decrease relative to that of protein composition a.

Claims

1. A method for producing a bean protein composition, the method comprising the following steps: i) dry heat treating the pulse seeds at a temperature between 70°C and 130°C for a period of 2 minutes to 6 minutes; ii) grinding the seeds into powder and suspending them in an aqueous solution; iii) separating the soluble components from the suspension using centrifugal force; iv) Extraction of proteins from the soluble fraction, wherein, during the thermal treatment, heat is provided by convection, Wherein, the heat treatment is performed without controlling the relative humidity.

2. The method according to claim 1, characterized in that In step i), the pulse seeds are dry heat treated at a temperature between 80°C and 125°C.

3. The method according to claim 2, characterized in that In step i), the pulse seeds are dry heat treated at a temperature between 100°C and 120°C.

4. The method according to claim 1, characterized in that: In step i), the pulse seeds are dry heat treated for 2 to 5 minutes.

5. The method according to claim 4, characterized in that In step i), the pulse seeds are dry heat treated for 2 to 4 minutes.

6. The method according to claim 1, characterized in that The powder in step ii) is suspended in an aqueous solution, wherein the concentration of dry matter in the suspension is 15% to 25%.

7. The method according to claim 6, characterized in that The concentration of dry matter in the suspension was 20%.

8. The method according to claim 1 or 6, characterized in that: Step iv) protein extraction comprises the following steps: - Coagulation of proteins in aqueous solution at a pH between 4 and 6 and heat treatment at a temperature between 45°C and 65°C.

9. The method according to claim 8, characterized in that The protein in the aqueous solution was coagulated at a pH of 4 to 6 and heat treated at a temperature of 55°C.

10. The method according to claim 8, further comprising the steps of: - recovering the coagulated protein obtained by centrifugation and suspending the protein in an aqueous solution; - adjusting the pH value of the aqueous solution to between 6 and 8; - heat treating the aqueous protein solution at a temperature between 130°C and 150°C for 5 seconds to 15 seconds.

11. The method according to claim 10, characterized in that The pH value of the aqueous solution was adjusted to 7.

12. The method according to claim 10, characterized in that The aqueous protein solution was heat treated at 140°C.

13. The method according to claim 10, characterized in that The aqueous protein solution was heat treated for 10 seconds.

14. The method of claim 1, further comprising a drying step of the aqueous protein suspension.

15. The method according to claim 1, characterized in that The legume seeds are selected from peas, lupines and broad beans.

16. The method according to claim 15, characterized in that The legume seeds are pea seeds.

17. A pulse protein composition obtainable by the method according to any one of claims 1 to 16.

18. Use of the bean protein composition according to claim 17 in food production.

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