Fibre extracted from tubers

Abstract

The invention relates to a powder of fibre extracted from tubers, comprising a tuber dietary fibre content of at least 30% determined according to the AOAC 985.29 method, and characterized in that it exhibits: - an oil absorption capacity, determined according to TEST A, ranging from 4.0 to 7.5 g of oil / g of powder; - a hydration capacity, determined according to TEST B, ranging from 10.0 to 20.0 g of water / g of powder. The invention also relates to a method for manufacturing said fibre.

Description

[0001] Description

[0002] Fiber extracted from tubers

[0003] Scope of the invention

[0004] The invention relates to a novel fiber powder extracted from tubers, comprising an improved oil absorption capacity. A second object of the invention relates to a method for manufacturing said fiber. A third object of the invention relates to the use of said fiber in the manufacture of food products.

[0005] Previous art

[0006] Keen to find solutions that benefit their health and well-being, modern consumers seek foods and dietary supplements that can help them achieve these goals.

[0007] Among the ingredients used to create these types of foods, those containing dietary fiber are of particular interest. In recent dietary trends, the consumption of foods containing fiber has tended to decrease. This is largely due to the fact that the food industry has grown significantly in recent decades, driven by consumer demand for prepared products, and that few fiber-based products readily available to this industry have been offered during this period.

[0008] In natural products, fruits and vegetables, particularly tubers, contain varying amounts of dietary fiber. This dietary fiber can be extracted and concentrated through separation processes to form tuber fiber compositions, also known as extracted tuber fiber. Tubers contain plant cell walls that include starch granules. These cell walls form the tuber fibers, which, in their wet state, often consist of fragments exceeding 1 millimeter in length and containing numerous open cavities. These extracted tuber fibers offer a range of nutritional benefits, and numerous studies have demonstrated the diverse advantages of dietary fiber in the human diet, such as reducing blood sugar and cholesterol levels.Furthermore, these fibers extracted from tubers are low in calories.

[0009] In addition to their undeniable nutritional value, the morphology (size, shape, cavities) of these fibers extracted from tubers after drying, generally in powder form, also allows them to exhibit interesting physicochemical properties, particularly in food applications. Several documents have described tuber-extracted fibers with such properties. For example, document FR 2331293 A1 describes the use of potato pulp in the production of fruit compotes, marmalades, sauces, and tomato-based preparations. These products are made by directly introducing potato pulp (or extracted potato pulp containing fiber) in powder form, or by introducing a dispersion of this pulp in water.The pulp contains starch in gelatinized form, proteins, minerals, fats, as well as cellulosic matter and other polysaccharides. The fact that the starch is gelatinized, notably by drying on a drum dryer, allows this potato pulp to exhibit these enhanced properties. Furthermore, the powder's high hydration capacity stems from the presence of fibers, which are particularly adept at retaining water. The pulpy texture is also due to the presence of cell walls, which swell after hydration. This document is silent regarding its oil absorption capacity.

[0010] Document WO88 / 01138 A1 describes a process for manufacturing potato fibers with improved taste, including various fiber pressing stages. The fibers' water adsorption capacity is mentioned, but the document remains silent regarding their oil absorption capacity. One advantage of the process is the minimal introduction of water, achieved by using process water. Specifically, in the final process stages, the pulp is pressed before drying to remove as much of the juice as possible, for example, using a screw press. Before drying, this pressed fiber can also be remixed with dry fiber to obtain the highest possible dry matter content, generally around 50%, before the final drying stage, which is carried out using conventional methods with hot air in cyclones.

[0011] US patent 2008 / 0226807 A1 describes potato fibers with high fiber content, ranging from 70 to 75%, low color, and good hydration capacity. It is silent regarding their oil absorption capacity. To produce such fibers, the wet fiber suspension is drained to obtain a high dry matter content, in the same manner as described in WO88 / 01138 A1. The resulting wet fiber suspension is then mixed with already dried fiber in a ratio of 1:1 to 1:6, and the mixture is fed into conventional dryers. However, as will be demonstrated later, this type of process does not produce fibers with a high oil absorption capacity.

[0012] Fibers extracted from tubers using known methods generally exhibit low oil absorption capacities, in contrast to their hydration capacities. For example, see the document by Ktari et al., "Chemical composition, techno-functional and sensory properties and effects of three dietary fibers on the quality characteristics of Tunisian beef sausage," Meat Science 96 (2014) 521-525. Ktari determined a hydration capacity of 6 g / g and an oil absorption capacity of 2.5 g / g for the product VITACEL KF500, marketed by JRS.

[0013] In the document "Techno-Functional Properties of Three Dietary Fibers Used in the Meat Processing Industry" (Proceedings of the 13th International Symposium "Modern Trends in Livestock Production," October 6-8, 2021, Belgrade, Serbia), Stanisic et al. compare the oil absorption capacities of potato fiber, wheat fiber, and oat fiber. They attribute the oil absorption capacity to the fiber composition and the porosity of the powder. According to this document, Paselli FP potato fiber, marketed by AVEBE, has the highest oil absorption capacity of the three, determined to be close to 5.9 g / g of fiber. It should be noted, however, that the method used by Stanisic et al. involves centrifuging the fiber and oil mixture, removing the supernatant oil, weighing the oil-absorbed fiber, and then dividing by the initial quantity of dry fiber used.Therefore, the amount of oil adsorbed obtained using this method incorrectly includes the initial mass of dry fiber. If the initial amount of dry fiber (before absorption) is not taken into account when calculating the amount of oil absorbed per gram of dry fiber, the oil absorption capacity obtained using this method should be considered to be close to 4.9 g / g of fiber. Furthermore, potato fiber, according to Stanisic et al., exhibits a hydration capacity of 9.5 g / g of fiber, a value that appears higher than that described for VITACEL KF500 fiber in the aforementioned Ktari et al. document. Stanisic et al. explain the higher hydration capacity by the difference in nature between the two commercial products. However, this higher value appears to be due to the method used by Stanisic et al.And, as the inventors have demonstrated later in the examples section of this application, the hydration capacity of Paselli FP fiber is actually also limited. Indeed, Stanisic et al. obtained a value of 9.5 g / g of fiber for the fiber extracted from apples, whereas, as with the oil absorption capacity method, this hydration capacity value also incorrectly accounts for the initial mass of dry fiber. Thus, the hydration capacity value according to this document should therefore be considered to be 8.5 g / g. It follows that, while the oil absorption capacity of Paselli FP fiber appears to be relatively high according to Stanisic et al., this fiber would not have a high hydration capacity according to this document, e.g., of at least 10 g of water / g of fiber powder.

[0014] Thus, none of the documents above described tuber-derived fibers exhibiting both high oil absorption and hydration capacities. However, this type of ingredient can be useful in human nutrition, for example, in dietetic food products containing water and fat, such as meat substitutes (emulsified sausages, plant-based steaks, etc.), or in the production of ice cream or sauces. It follows from the above that there is a need to provide a tuber-derived fiber powder with both high oil absorption and hydration capacities.

[0015] Summary of the invention

[0016] The invention thus relates to a fiber powder extracted from tubers comprising a tuber dietary fiber content determined according to method AOAC 985.29 of at least 30%, and characterized in that it exhibits:

[0017] - an oil absorption capacity, determined according to TEST A, ranging from 4.0 to 7.5 g of oil / g of powder;

[0018] - a hydration capacity, determined according to TEST B, ranging from 10.0 to 20.0 g of water / g of powder.

[0019] One of the advantages of the present invention is that the powder can exhibit this high oil absorption capacity, even when the amount of dietary fiber in the powder varies and decreases, e.g., to around 50%. Thus, even when the amount of dietary fiber is lower, it is possible to maintain the oil retention capacity. Without being bound to any specific theory, the inventors explain the improved absorption capacity of the powder by a morphology that appears different, as shown in the Figures, although difficult to characterize other than the indirectly obtained functional property. It appears that this also contributes to achieving this high hydration capacity.

[0020] Another object of the invention relates to a process for manufacturing fiber powder extracted from tubers according to the invention, comprising:

[0021] - a step of supplying an aqueous mixture of fiber extracted from tuber having a dry matter content of 15 to 45% by mass, based on the total mass of the aqueous mixture;

[0022] - a drying step of the aqueous mixture to form a powdery composition in a pneumatic dryer supplied with hot air such that the temperature of the air exiting the dryer is between 80 and 120°C, in which at least one disintegration stage of the aqueous mixture is carried out inside the dryer;

[0023] - optionally a sieving step of the powdery composition obtained during the previous step using a sieve with a mesh size ranging from 500 to 2500 pm to separate on one side the agglomerates of particles and on the other the fiber powder extracted from tuber.

[0024] Another object of the invention relates to the use of the fiber extracted from tubers according to the invention for the manufacture of food or beverage products.

[0025] Description of the figures

[0026] Fig. 1

[0027] Figure 1 represents a potato fiber powder according to the invention observed by optical microscopy with a magnification of x8 and x30.

[0028] Fig. 2

[0029] Figure 2 represents a comparative potato fiber powder observed by optical microscopy with x8 and x30 magnification.

[0030] Detailed description of the invention

[0031] The invention will now be described in detail below.

[0032] The invention relates to a fiber powder extracted from tubers. More specifically, the fiber powder extracted from tubers has:

[0033] - an oil absorption capacity, determined according to TEST A, ranging from 4.0 to 7.5 g of oil / g of powder;

[0034] - a hydration capacity, determined according to TEST B, ranging from 10.0 to 20.0 g of water / g of powder.

[0035] The oil absorption capacity, for example of corn oil, quantifies the fiber's ability, after contact with oil, to retain the oil after centrifugation. This absorption capacity is indicated per gram of oil absorbed per gram of powder, i.e., per gram of powder before contact with the oil. It is determined according to the invention by TEST A, performed at a temperature of 20-25°C, which consists of:

[0036] -Record the mass of a 25 ml graduated centrifuge tube (M1).

[0037] - Weigh directly into the tube the equivalent of 1 g of sample of fiber powder extracted from tuber (M2).

[0038] - Prepare, using a test tube, 20 ml of corn oil, for example COPPELIA brand.

[0039] - Pour approximately 10 ml of oil over the sample and then vortex at maximum speed, for example in an IKA® Genius 3 laboratory vortex shaker, for 5 minutes.

[0040] - Fill the tube with the remaining 10 ml of oil from the test tube, then manually shake the tube up and down ten times.

[0041] - Let the tubes rest for 10 minutes, manually shake the tube up and down ten times then let it rest for another 10 minutes, manually shake the tube up and down ten times then let it rest for another 10 minutes.

[0042] -Centrifuge at 60,000 g for 30 min.

[0043] - Decant the supernatant (oil) and carefully invert the tube to empty it. Weigh the M3 tube.

[0044] The mass of oil absorbed per gram of product is calculated as follows:

[0045] [Math. 1] with :

[0046] M1 = mass of the empty tube in g

[0047] M2 = mass of tube + dry sample in g

[0048] M3 = mass of tube + sample after centrifugation and removal of excess oil.

[0049] Hydration capacity quantifies the fiber's ability, after contact with water, to retain water after centrifugation. This absorption capacity is indicated by grams of water absorbed per gram of powder before absorption, i.e., per gram of dry powder brought into contact with water. It is determined according to the invention by TEST B performed at 20-25°C, which consists of:

[0050] - Tare the scale, then weigh the empty centrifuge tube using a magnetic stir bar (m tube). - Add 40 ml of demineralized water and shake for 1 hour at 900 rpm.

[0051] - Centrifuge for 20 minutes at 3000G

[0052] - Decant the supernatant (water) and carefully invert the tube to empty it. Weigh the tube plus the sediment, i.e., total HL

[0053] - Calculate the capacity according to the following equation, expressed in g of water absorbed per g of sample

[0054] [Math. 2] mtotale - mtube — mech)

[0055] Hydration capacity = mech

[0056] This method corresponds, with more details, to the method described in document US2008 / 0226807A1.

[0057] The term "tuber-extracted fiber" according to the present invention means a composition rich in dietary fiber, with a tuber dietary fiber content determined according to AOAC method 985.29 of at least 30%, obtained by an extraction process using at least one tuber as raw material. In the following, the terms "tuber-extracted fiber" are equivalent to the terms "tuber fiber" or "pulp".

[0058] The oil and water absorption capacities are defined in relation to the total mass of the fiber powder extracted from the tuber, before being brought into contact, respectively, with oil or with water.

[0059] In addition to their undeniable nutritional value, already discussed, the morphology (size, shape, cavities) of these fibers extracted from dried tubers, as well as their composition, also give them interesting physicochemical properties, particularly in food applications. These properties include high hydration and oil absorption capacities.

[0060] The term "tuber" should be understood in its usual sense and refers to any type of tuber. A tuber in this definition may originate from roots or stems.

[0061] Generally, a tuber is an edible plant, notably used for human food production. Tubers inherently contain dietary fiber. Preferred types of tubers are also rich in starch. Preferably, tubers are chosen from among potatoes, sweet potatoes, cassava, or yams; even more preferably, tubers are chosen from among potatoes, sweet potatoes, or cassava; even more preferably, tubers are chosen from among potatoes or sweet potatoes.

[0062] Preferably, the tuber is the potato (Solarium tuberosum).

[0063] To improve the oil absorption and hydration capacities of fibers extracted from tubers, increasing their dietary fiber content is a known method. For example, the potato fiber described in Stanisic et al. contains 70–75% dietary fiber by mass, with an oil absorption capacity of 5.9 g / g per 1 g of potato fiber. Similarly, the fibers in US patent 2008 / 0226807 A1 also contain 70–75% dietary fiber. However, increasing the amount of dietary fiber is not the only way to improve these absorption capacities. Indeed, the properties of dry tuber fiber powder also depend on the morphology of the particles that make up the powder.One of the advantages of the present invention is the ability to provide a tuber-extracted fiber powder with high hydration and oil absorption capacities, while potentially containing less than 70% dietary fiber. Since these properties depend on numerous complex parameters, particularly the number of cavities present and accessible to water and oil, which are difficult to describe, it is common practice for those skilled in the art to characterize these tuber-extracted fibers directly by their physicochemical properties, especially their hydration capacity and even their oil absorption capacity.The inventors were able to confirm that oil absorption and hydration capabilities may depend on other parameters such as particle size and apparent density, these properties tending to increase with particle size but hypothesize that they also depend on the shape and quantities of cavities in the fiber.

[0064] Preferably, the fiber powder extracted from tuber according to the invention has an oil absorption capacity, determined according to TEST A, ranging from 4.5 to 7.0 g of oil / g of powder, by ranging from 5.0 to 7.0 g of oil / g of powder or even for example from 5.3 to 6.4 g of oil / g of powder.

[0065] Preferably, the fiber powder extracted from tuber according to the invention has a hydration capacity, determined according to TEST B, ranging from 12.0 to 17.0 g of water / g of powder.

[0066] A "high-fiber composition" generally means a composition containing at least 30% by mass of tuber-derived dietary fiber, relative to the total mass of the composition. Unless explicitly stated otherwise, the amount of tuber-derived dietary fiber in this application is the total amount of dietary fiber determined according to AOAC Standard 985.29.

[0067] For example, the total amount of tuber dietary fiber in tuber-extracted fiber powder may be equal to or greater than 40% by mass, in particular ranging from 40 to 80% by mass, relative to the total dry mass of the powder. Advantageously, the total amount of tuber dietary fiber in tuber-extracted fiber ranges from 40 to 68% by mass, advantageously from 45 to 65% by mass, and preferably from 50 to 60% by mass, relative to the total dry mass of the powder.

[0068] Unless explicitly stated otherwise, the relative quantities of the other different constituents of the fiber extracted from tuber are expressed as mass percentages (i.e. by weight) expressed in relation to the total dry mass (i.e. weight) of the fiber powder extracted from tuber.

[0069] Tuber-extracted fiber powder may be dry and have a dry matter content of 80% or more by mass, advantageously ranging from 85% to 95% by mass, relative to the total mass of the powder. The dry matter content of tuber-extracted fiber powder can be determined using an infrared moisture balance. Tuber-extracted fiber powder also generally contains tuber starch, tuber proteins, and minerals.

[0070] Advantageously, the mass percentage of tuber starch in the tuber-extracted fiber powder, expressed as a percentage of the dry mass of the tuber-extracted fiber powder, may range from 10 to 45% by mass, preferably from 15 to 35% by mass, and more preferably from 15 to 25% by mass. The amount of tuber starch in the present application can be determined by known methods. The starch content of the tuber-extracted fiber powder can be determined by calculating the total mass percentage of tuber starch relative to the total weight of the tuber-extracted fiber powder.The amount of starch can be determined by multiplying by 0.9 (the glucose-to-starch conversion factor) the amount of glucose released upon hydrolysis of a sample with an amyloglucosidase. This amount of glucose released is obtained by subtracting the free glucose from the fiber powder extracted from the tuber from its total glucose obtained after hydrolysis. Glucose determinations can be performed by enzymatic determination of glucose using the hexokinase method, for example, using kit Cat. No. 10 716 251 035 from R-BIOPHARM. In the Examples section, the following method was used:

[0071] 1. Add approximately 750 mg of tuber fiber powder with a known dry matter content to a glass jar fitted with an airtight lid.

[0072] 2. Add 100 ml of distilled water to the test tube and mix.

[0073] 3. Adjust the pH of the aqueous suspension to 6.5 (Adjustment using 0.1 N HCl or 0.1 N NaOH)

[0074] 4. Place the jar in a 100°C water bath for 3 minutes, shaking the jar. Then transfer it to a 130°C oven for one hour, keeping the jar closed.

[0075] 5. After removing them from the oven, leave them on the work surface for 10 minutes before cooling them in a water bath at 20°C and depressurizing the jar.

[0076] 6. Add 5 mL of 1.2 M sodium acetate solution, check the pH and adjust the pH to 4.6 if necessary (with 0.1 N HCl or 0.1 N NaOH).

[0077] 7. Add 500 L of amyloglucosidase (E-AMGDF from Megazyme).

[0078] 8. Place the jar in a water bath at 60°C for 2 hours.

[0079] 9. Remove the jar and, after cooling, transfer the mixture to a 500 mL volumetric flask and fill to the mark with distilled water. Mix and filter through a pleated paper filter with an 8 µm pore size, for example, Whatman® brand.

[0080] 10. Perform the enzymatic determination of glucose by the hexokinase method to obtain the total glucose released (kit Cat. No. 10 716 251 035 at R-BIOPHARM) then determine the total glucose per gram of powder.

[0081] 11. Analyze free glucose: Dissolve 5 g of tuber fiber powder sample in 250 mL of distilled water and stir with a magnetic stir bar for 1 hour. Filter through pleated filter paper with a pore size of 8 µm, such as Whatman® brand. Collect the filtrate to perform glucose determination using the hexokinase method described above, and then determine the free glucose per gram of powder.

[0082] 12. Calculate the total mass percentage of tuber starch relative to the total weight of the powder: (total glucose released per gram of powder - free glucose per gram of powder) x 0.9 (glucose to starch conversion factor) x 100.

[0083] From this total mass content of tuber starch and the dry matter of the fiber powder, it is possible to calculate the mass quantity of tuber starch in the fiber powder extracted from tuber, expressed in relation to the dry mass of the fiber powder extracted from tuber.

[0084] The mass percentage of N6.25 protein from tubers in the extracted tuber fiber powder, expressed as a percentage of the dry mass of the extracted tuber fiber powder, is generally equal to or less than 10% by mass, for example, from 0.1 to 10% by mass. Advantageously, the mass percentage of tuber protein in the extracted tuber fiber powder, expressed as a percentage of the dry mass of the extracted tuber fiber, is equal to or less than 6% by mass, for example, from 2 to 5% by mass, in particular from 2.5 to 4.5% by mass. The amount of N6.25 protein from tubers in the extracted tuber fiber powder of this application is the amount of protein determined according to the DUMAS method, the result obtained for nitrogen according to the method being multiplied by the factor 6.25 to express the mass percentages of N6.25 protein.

[0085] From this mass content of tuber protein and the dry matter of the fiber powder, it is possible to calculate the mass quantity of tuber protein in the fiber powder extracted from tuber, expressed in relation to the dry mass of the fiber powder extracted from tuber.

[0086] The mass percentage of minerals in the fiber powder extracted from tubers, expressed as a percentage of the dry mass of the fiber powder extracted from tubers, is generally equal to or less than 7% by mass, for example, from 0.1 to 7% by mass. Advantageously, the mass percentage of minerals in the fiber powder extracted from tubers, expressed as a percentage of the dry mass of the fiber powder extracted from tubers, is equal to or less than 3.5% by mass, or is equal to or less than 3.2% by mass, or is equal to or less than 3% by mass, for example, ranging from 1 to 3% by mass, in particular from 1.5 to 2.9% by mass.

[0087] The quantity of minerals in the fiber powder extracted from tuber of this application can be obtained by measuring the quantity of minerals expressed relative to the wet mass of a sample of fiber powder extracted from tuber with a known dry matter content, using for example the following method:

[0088] - In a gondola previously dried and weighed (m1), then tareed and introduce a test sample mO.

[0089] - Carefully heat the basket and its contents on the hot plate until the test sample is completely carbonized. Then place the basket in the oven set at 550°C plus or minus 20°C until the carbon residue disappears.

[0090] - Place the gondola and the residue in the desiccator, allow to cool to room temperature, and weigh, i.e. m2

[0091] - The residue after calcination represents the quantity of minerals, expressed as a percentage by mass, obtained from the sample as such, and is given by the formula:

[0092] [Math 3]

[0093] (m2 — ml) X 100 mO where: mO is the mass, in grams, of the test sample, m1 is the mass, in grams, of the empty gondola before incineration, m2 is the mass, in grams, of the gondola after incineration.

[0094] From this mass quantity of minerals and the dry matter of the fiber powder, it is possible to calculate the mass quantity of minerals in the fiber powder extracted from tuber, expressed in relation to the dry mass of the fiber powder extracted from tuber.

[0095] Fiber powder extracted from tubers may contain other residual compounds such as glycoalkaloids, phenolic compounds, the enzyme polyphenol oxidase, or sugars. However, these compounds are generally removed during the extraction process, and the total amount of constituents other than tuber dietary fiber, tuber starch, minerals, tuber proteins, and water is generally equal to or less than 1% by mass, or even equal to or less than 0.1% by mass, relative to the dry mass of the powder.

[0096] A powder is made up of particles of different sizes. Fiber extracted from tubers can therefore be a powder of fiber extracted from tubers. This fiber powder can thus consist of particles of different sizes.

[0097] The powder can be characterized by a particle size d50. In the present invention, "d50" refers to the particle size in microns that separates the particles into two populations by volume, each containing 50% of the smallest particles and 50% of the largest particles, the percentage being relative to the total number of particles in the fiber powder extracted from the tuber. The fiber powder extracted from the tuber of the invention can have a d50 equal to or greater than 330 µm, advantageously from 350 to 500 µm, preferably from 380 to 460 µm.

[0098] Furthermore, to characterize the particle population distribution within the powder, the particle sizes d10 and / or d90 can be used. In the present invention, "d10" refers to the particle size in microns that divides the powder into two populations by volume, containing respectively 10% of the smallest particles and 90% of the largest particles, this percentage being relative to the total number of particles in the fiber powder extracted from the tuber. Similarly, "d90" refers to the particle size in microns that divides the powder into two populations by volume, containing respectively 90% of the smallest particles and 10% of the largest particles, this percentage being relative to the total number of particles in the fiber powder extracted from the tuber. The fiber powder extracted from the tuber according to the invention can have a size d10 equal to or greater than 100 µm, advantageously from 120 to 200 µm, and preferably from 140 to 190 µm.The fiber powder extracted from tuber according to the invention can have a size d90 equal to or greater than 500 pm, advantageously from 700 to 1200 pm, preferably from 750 to 1000 pm.

[0099] Particle sizes d10, d50, and d90 can be determined using a dry method by laser granulometry with the Fraunhofer optical model. For example, Malvern Mastersizer models, such as the Malvern Mastersizer MS 3000+, can be used, following the instructions in the manual.

[0100] The fiber powder extracted from tubers according to the invention can also have an apparent density ranging from 0.10 to 0.20 g / ml. The apparent density indirectly quantifies the cavities formed within the particles, as well as the air that may intrude between them, which can also influence the absorption capacity properties. The density can be determined conventionally, for example, using the following method:

[0101] Wash and dry the test tube, then weigh it (mO).

[0102] Fill the test tube to the brim with distilled water and weigh again (m1)

[0103] Empty, wash, and dry the test tube. Pour the sample into the hopper, allowing it to flow freely into the test tube until it is filled to the brim.

[0104] Trim off the excess product

[0105] Weigh the test tube with its contents (m2)

[0106] The density, expressed in kg / L or g / ml, is given by the formula below:

[0107] [Math 4] m2 — mO

[0108] — — — — xp ml - mO r where: m0 = mass (g) of the empty and dried test tube; m1 = mass (g) of the test tube filled with water; m2 = mass (g) of the test tube and its contents; ρ = density (in g / mL) of water at the temperature of the determination

[0109] The inventors have thus succeeded in obtaining fiber powders extracted from dried tubers exhibiting high hydration and oil content. The manufacturing process will now be described in detail, and in particular the method for preparing the powder, including a specific drying process. One of the objects of the invention relates to a process for manufacturing tuber fiber powder according to the invention, comprising:

[0110] - a step of supplying an aqueous mixture of fiber extracted from tuber having a dry matter content of 15 to 45% by mass, based on the total mass of the aqueous mixture;

[0111] - a drying step of the aqueous mixture to form a powdered composition in a pneumatic dryer supplied with hot air such that the temperature of the air exiting the dryer is between 80 and 120°C, in which at least one disintegration stage of the aqueous mixture is carried out inside the dryer,

[0112] - optionally a sieving step of the powdery composition obtained during the previous step using a sieve with a mesh size ranging from 500 to 2500 pm to separate on one side the agglomerates of particles and on the other the fiber powder extracted from tuber.

[0113] To provide an aqueous mixture of fiber extracted from tuber, conventional methods of extracting fiber from tuber already known are used.

[0114] To achieve this, the tubers are generally subjected to a preliminary washing stage. This washing stage allows for the removal of soil and other residues such as weeds, stones, and pebbles. It can be carried out using conventional methods, for example by washing in water or by pressure washing the tubers.

[0115] According to one embodiment, the tubers may also optionally undergo a preliminary peeling step. The peels may be removed during the process.

[0116] The process generally involves grinding the tubers in an aqueous solution to produce a suspension of ground tubers, followed by a fractionation step of the ground tuber suspension to provide a "soluble fraction" consisting mainly of soluble proteins, minerals, and sugars, and an "insoluble fraction" consisting mainly of tuber dietary fiber and tuber starch. The soluble fraction is commonly referred to as "red waters." This soluble fraction also includes glycoalkaloids, phenolic compounds, and the enzyme polyphenol oxidase. The insoluble fraction also includes residual tuber proteins and minerals.

[0117] The grinding stage can be carried out using conventional wet grinding methods. This wet grinding stage is preferably a grating stage. This grating stage is generally performed by machines equipped with rotating drums fitted with blades: these are often referred to as industrial graters. This grating stage promotes the opening of the tuber cells and produces plant cell wall fragments with an elongated morphology and a larger particle size than potato starch.

[0118] To avoid enzymatic browning reactions caused by polyphenol oxidase in the presence of oxygen and phenolic compounds, it is best to perform this fractionation operation soon after the wet grinding of the tubers. Reducing agents can also be added to the aqueous solution or during the grinding stage to irreversibly inhibit polyphenol oxidase. These reducing agents can be sulfite or bisulfite derivatives such as sodium bisulfite or sodium metabisulfite.

[0119] Regarding the fractionation step of the crushed tuber suspension, the soluble fraction can be separated from the insoluble fraction using standard fractionation methods. These can include mechanical separation methods that do not separate starch from dietary fiber, such as filtration, decantation, and centrifugation, preferably using a decanter centrifuge or plate separators. The recovered insoluble fraction then contains tuber starch and dietary fiber, as well as insoluble proteins and remnants of the soluble compounds mentioned previously (proteins, sugars, minerals, etc.).

[0120] Alternatively, it is possible to perform wet sieving of the crushed tuber suspension. A wet sieving step consists of diluting an insoluble fraction, obtained during the crushing step, with water to obtain a suspension of this insoluble fraction, and then passing this suspension through a sieving cloth, for example using centrifugal sieving equipment from brands such as Stamex, Nivoba, Larsson™ or Siccadania.This wet sieving step of the crushed tuber suspension is carried out in such a way as to recover a fraction passing through the sieve comprising the majority of the starch and soluble compounds and an insoluble fraction retained in the sieve which contains constituents of the same nature as mechanical separation methods do not separate starch from dietary fiber (tuber starch, tuber fiber, insoluble tuber protein as well as remnants of soluble compounds) but in different proportions, i.e. that the fraction remaining on the sieve is comparatively richer in dietary fiber and less rich in starch.

[0121] The process may further include at least one step of enriching the insoluble fraction obtained from the fractionation step or from the wet sieving step with dietary fiber. This step may also be carried out by wet sieving. Thus, enrichment can be achieved through successive wet sievings. This sieving is generally performed using rotary sieves. At the end of this dietary fiber enrichment step, a fiber-enriched insoluble fraction extracted from tubers is obtained, having the dietary fiber, starch, mineral, and protein compositions defined above.

[0122] During the wet sieving stages, the dry matter content of the crushed tuber suspension can vary, preferably from 10 to 20% by mass, based on the total mass of the suspension. At this stage, using a lower dry matter content (e.g., 10% by mass) results in a greater enrichment in dietary fiber than using a higher dry matter content (e.g., 20% by mass). This is illustrated in the Examples section, in Examples 1 and 2. The choice of parameters during these sieving stages, particularly their number and the dry matter content of the suspension, allows for the adjustment of the desired dietary fiber content. Furthermore, depending on the preferred variant where the tuber-extracted fiber has reduced amounts of protein and minerals, as described previously, the process includes a specific final wet sieving stage.

[0123] First, it's important to clarify that in industrial tuber fiber extraction processes, process water is systematically recycled at various points in the process for reuse in different stages, in accordance with sustainability principles. Therefore, in these industrial processes, there are generally no process water streams that haven't been in the circuit at all. These water streams typically have a dry matter content of 20% or less by mass and can contain up to 80% starch by mass relative to the dry matter content, with the remaining dry matter consisting primarily of tuber fiber, tuber protein, and minerals.However, to achieve the aforementioned reduced quantities of minerals (equal to or less than 3.5% by mass or equal to or less than 3% by mass) and tuber protein (equal to or less than 6% by mass) in the extracted tuber fiber during the final wet sieving step, dilution must be carried out with a water stream having a dry matter content equal to or less than 2% by mass, based on the total mass of the stream. Preferably, the water stream used for dilution has a protein content equal to or less than 1% by mass, or even equal to or less than 0.5% by mass, and preferably a mineral content equal to or less than 0.8% by mass, or even equal to or less than 0.4% by mass, based on the total mass of the stream.Furthermore, this wet sieving must be carried out using sufficient quantities of water to obtain a tuber protein content, expressed as a percentage of the dry matter of the powder, equal to or less than 6%, and a mineral content, expressed as a percentage of the dry matter of the powder, equal to or less than 3.5% or equal to or less than 3%. Thus, on an industrial scale, those skilled in the art will adjust the water flow according to the quantities of product to be sieved, in order to regulate the dry matter, protein, and mineral content of the dilution water, thereby enabling the production of the desired tuber fiber.

[0124] Following this extraction by fractionation or wet sieving, an aqueous composition of tuber fiber is obtained, with the dry matter content potentially varying. Generally, after the aforementioned conventional sieving steps, the dry matter content of this aqueous tuber fiber composition ranges from 5 to 15% by mass relative to the total mass of the aqueous composition. Preferably, an additional concentration step is carried out to achieve an aqueous tuber fiber composition with a dry matter content ranging from 18 to 25% by mass relative to the total mass of the composition, for example, by using a decanter centrifuge or passing the fiber through a press or belt filter.According to a first variant, the aqueous composition of tuber-extracted fiber is concentrated to provide an aqueous tuber-extracted fiber mixture with a dry matter content of 15 to 45% by mass, relative to the total mass of the aqueous tuber-extracted fiber mixture. According to a preferred variant, the aqueous tuber-extracted fiber mixture is obtained by mixing, using a mixer, the aqueous tuber-extracted fiber composition (obtained during the fractionation or wet sieving steps and the optional wet sieving concentration steps) and a dry tuber-extracted fiber composition.According to this variant, the aqueous composition of tuber-extracted fiber is mixed with a portion of the dry potato fiber obtained from the dryer. This portion can be recycled upstream of the feed and mixed with the aqueous composition of tuber-extracted fiber to provide a homogeneous aqueous mixture of tuber-extracted fiber with a dry matter content ranging from 15 to 45% by mass, for example, 30 to 45% by mass, relative to the total mass of the homogeneous aqueous mixture of tuber-extracted fiber. This mixing can be carried out using a paddle mixer, such as a double-shaft paddle mixer or a Ploughshare mixer from Lôdige, to obtain a non-sticky, homogeneous, and lump-free dispersible mixture.According to this variant, the aqueous composition of fiber extracted from tuber and the dry composition of fiber extracted from tuber can be introduced in a mass ratio of 1 / 0.15 to 1 / 0.5. Therefore, in this variant, the aqueous mixture of fiber extracted from tuber is obtained by mixing an aqueous composition of fiber extracted from tuber and a dry composition of fiber extracted from tuber from the drying stage in a mass ratio of 1 / 0.15 to 1 / 0.5.

[0125] The process according to the invention further includes a step of drying the wet mixture to form a powdery composition in a pneumatic dryer supplied with hot air such that the temperature of the air exiting the dryer has a temperature between 80 and 120°C, in which at least one stage of disintegration of the wet mixture is carried out inside the dryer.

[0126] A pneumatic flash drying system, also called a flash dryer, is a type of dryer used in various industries to dry materials. Here is an explanation of its operation and main characteristics: the aqueous mixture of fiber extracted from tubers is fed into the dryer through a hopper or feeding system and then exposed to a high-velocity stream of hot air. This hot air can be produced by a gas burner, a heat exchanger, or another heat source. The hot air transfers its heat to the material, causing the moisture in the mixture to evaporate rapidly. Evaporation occurs almost instantaneously due to the direct contact between the mixture and the hot air. The dried mixture is then conveyed to a drying chamber or a conveying pipe where it continues to be exposed to the hot air.Drying is completed during transport. Once the mixture is dry, it is separated from the hot air. This separation typically occurs in a cyclone separator or baghouse, where the dry mixture is collected as a powder, and the air is exhausted. Examples of flash dryers include pneumatic dryers, as well as more specialized flash dryers such as rotary flash dryers (also known as spin flash dryers) or ring dryers (also known as ring dryers) from the Dedert brand. These technologies, well-known to those skilled in the art, are described, for example, in Borde et al., Pneumatic and Flash Drying, Chapter 16, Handbook of Industrial Drying, Fourth Edition, published on November 8, 2006, DOI: 10.1201 / 9781420017618.ch16. According to the invention, the temperature of the dryer outlet air is between 70 and 150°C, for example between 80 and 120°C.The skilled person can adjust the conditions of the supply flow rate of the homogeneous aqueous mixture, the volumetric flow rate of the air and the inlet air temperature in order to obtain the desired outlet temperature.

[0127] According to the invention, the drying step to produce the powder composition includes at least one disintegration stage of the wet mixture carried out inside the dryer. Disintegration is understood to mean the application of shear force to form wet particles. Without being bound to any particular theory, the inventors believe that by applying this shear force to the homogeneous wet mixture of defined dry material, wet particles of a more elongated and / or more porous shape are formed, leading to fiber powders with different properties. Thus, after pneumatic drying, a powder composition comprising these particles in dry form is obtained. This disintegration stage can be carried out using dispersing rotors comprising blades, vanes, hammers, or knives.This disintegration stage is preferably carried out immediately after the introduction of the wet mixture, at the beginning of the drying step. Alternatively, this disintegration stage is carried out during the drying process. In one embodiment, the drying step includes a disintegration stage carried out at the beginning of the drying process and a disintegration stage carried out during the drying process. Spin-flash dryers can be used to carry out this drying step, which includes this disintegration stage. These dryers are described in particular by Borde et al. in the Handbook of Industrial Drying, Fourth Edition, 2006, in Chapter 16, Pneumatic and Flash Drying. Dryers of this type are available and marketed by companies such as Allgaier, Larsson, and Siccadania. Based on the information in the description, a person skilled in the art will be able to select a dryer in accordance with the teachings of Borde et al.and adapt the operating parameters, particularly shearing, to obtain the fiber powder extracted from the tuber of the invention.

[0128] Upon exiting the dryer, the fiber powder extracted from the tuber of the invention may have a dry matter content equal to or greater than 80% by mass, advantageously ranging from 85 to 95% by mass, relative to the total mass of the powder.

[0129] Upon exiting the dryer, an optional sieving step can be performed on the powdered composition obtained in the previous step. This can be carried out using a sieve with a mesh size ranging from 500 to 2500 µm to separate the particle agglomerates on one side and the extracted tuber fiber powder on the other. This sieve can be equipped with a magnet. Preferably, the sieve mesh size ranges from 800 to 2500 µm, for example, from 1000 to 2200 µm. The sieving step can be performed with a safety sieve equipped with a magnet. The manufacturing process may include an additional optional step for classifying the fiber particles. An example of a powder classification step is dry sieving, for example, using vibrating sieves.

[0130] Another object of the invention relates to the use of fiber powder extracted from tubers for the manufacture of food or beverage products.

[0131] In general, the fiber powder extracted from tubers according to the invention can be used in food and beverage products, which may contain up to 100% by weight relative to the total dry weight of the food or beverage, for example, from approximately 0.1% to approximately 10% by weight relative to the total dry weight of the food or beverage. All intermediate amounts and ranges based on these amounts may be used. These food and beverage products can be adapted for vegetarian or vegan populations.

[0132] In beverages, the fiber content extracted from tubers can vary widely. For example, the amount of fiber extracted from tubers can range from 0.1% to 10% by dry weight relative to the total mass of the beverage. Beverages can be of any type and include plant-based milk alternatives or milk substitutes, including barista-style milks and coffee creamers. Milk alternatives, including plant-based milk alternatives, can be manufactured from the tuber-extracted fiber powder according to the invention, along with fats, proteins, carbohydrates, and / or other optional ingredients that are emulsified to form the substitute. Alternatively, milk alternatives can be made from plant-based milks, such as oat milk, rice milk, soy milk, coconut milk, or almond milk.These plant-based milks can thus be supplemented with the fiber powder extracted from tuber according to the invention. It can also be other ready-to-drink beverages, acidic or not, such as carbonated beverages (including, but not limited to, carbonated soft drinks), non-carbonated beverages (including, but not limited to, non-carbonated soft drinks such as flavored waters, fruit juices and sweetened or unsweetened tea or coffee-based beverages), alcoholic beverages such as beers or spirits, smoothies, beverage concentrates (including, but not limited to, liquid concentrates and syrups as well as non-liquid "concentrates", such as freeze-dried and / or powdered preparations or "powder mixes")■.

[0133] The food products that may be affected include bakery products such as bread products (including, but not limited to, leavened and unleavened breads, sandwich breads, yeast breads and unleavened breads such as baking soda breads), breads containing all types of wheat flour, breads containing all types of flour other than wheat (such as potato, rice, barley, spelt and rye flours), gluten-free breads; mixes for preparing said bread products; sweet bakery products (including, but not limited to, rolls, cakes, pies, pastries, waffles, pancakes, muffins, pancakes, and biscuits); mixes for preparing said sweet bakery products;pie fillings and other sweet fillings (including, but not limited to, fruit pie fillings and nut pie fillings such as pecan pie fillings, as well as fillings for cookies, cakes, pastries, confectionery and other products, such as cream fillings); snack bars (including, but not limited to, energy, cereal, nut, and / or fruit bars).

[0134] This can also include set desserts such as custards, flans, and puddings. Another type of dessert can be frozen desserts (including, but not limited to, frozen dairy desserts such as ice cream – including regular ice cream, soft-serve ice cream, and all other types of ice cream – and frozen non-dairy desserts such as non-dairy ice cream, sorbet, and others).

[0135] Other products traditionally prepared from animal milk may also include the extract of fiber powder extracted from tubers according to the invention to form substitutes. These may be acidified and / or fermented products, such as lactic acid, vegan, or mesophilic cultures. They may include yogurts (including, but not limited to, full-fat, reduced-fat, and fat-free yogurts, which may be free of milk proteins and lactose). The term "yogurts" also includes Greek-style or skyr-type yogurts, which are high-protein yogurts (often containing 8 to 20 g of protein), as well as soft cheeses and fromage frais.This can also include cheese substitutes such as spreadable, processed, cooked and uncooked pressed cheeses, soft cheeses, stretched-curd cheeses, and blue cheeses; these can include Emmental, string cheese, ricotta, provolone, Parmesan, Munster, mozzarella, Monterey Jack, Manchego, blue cheese, Fontina, feta, Edam, Double Gloucester, Camembert, Cheddar, Brie, Asiago, and Havarti. It can also include other products such as vegetable butters or crème fraîche.

[0136] Other products that may include the fiber powder extracted from tuber according to the invention are also sauces such as tomato sauces, pesto, salad dressings or sauces based on mayonnaise or ketchup, soups or syrups.

[0137] Also, the fiber powder extracted from tubers according to the invention can be incorporated into confectionery products (including, but not limited to, gummy candies, soft candies, hard candies, chocolates, caramels, and gums); sweetened and unsweetened breakfast cereals (including, but not limited to, extruded cereals, flaked cereals, and puffed cereals); and cereal coating compositions for the preparation of breakfast cereals. It can also be used in sweet spreads (including, but not limited to, jellies, jams, nut butters such as peanut butter, spreads, and other spreadable products).

[0138] Other types of food and beverages not mentioned here but which typically contain one or more dietary fibers may also be considered within the scope of the present invention. In particular, animal feed (such as pet food like kibble or wet food) is explicitly considered.

[0139] The fiber powder extracted from tubers according to the invention can also be used in combination with proteins, optionally after texturizing, in meat substitutes such as emulsified sausages or hamburgers, or in fish or seafood substitutes. It can also be used in egg replacement formulations or for the manufacture of protein products such as tofu or tempeh. Textured proteins generally refer to proteins textured by extrusion, i.e., in particular, dry extrusion (also known as Textured Vegetable Protein) or high-moisture extrusion. The extruders can be single-screw, twin-screw, or multi-screw. In the case of twin-screw extrusion, the extrusion can be co-rotating or counter-rotating.Examples of multi-screw extrusion include the planetary extruder and the ring extruder. Other more specialized technologies include shear cell technology, microextrusion, and 3D printing.

[0140] The fiber powder extracted from the tuber can also be used mixed with meat, particularly minced or diced meat. The meat can be beef, veal, chicken, turkey, pork, or mutton. It can also be used in pâtés.

[0141] Food products or beverages can be used in specialized nutrition, for example for specific populations such as babies or infants, children, adolescents, adults, the elderly, athletes, and people with illnesses. These can include nutritional meal replacement formulas, complete nutritional drinks (for example, for weight management), or in clinical nutrition (for example, tube feeding or enteral nutrition).

[0142] A person skilled in the art will be able, on the basis of the above description and on the basis of the illustrative examples appearing later in the description, to supply the fiber extracted from the tuber of the invention.

[0143] Examples

[0144] Example 1: Fiber production including a step of drying wet pulp from a wet / dry mixture of 1 / 0.33

[0145] 80 tons per hour of pre-washed potatoes are fed into four industrial graters, each equipped with a 400 mm diameter drum. 0.8 liters per hour of a 39% (mass) sodium bisulfite solution are introduced at the grater. The resulting grated potato has a dry matter content of 24.3% (mass), based on the total mass of the grated potato.

[0146] This grated material is then fed into centrifugal decanters to obtain solid sediments containing mainly starch and fiber with a dry matter content of 43% by mass, based on the total mass of the sediments. The sediments are then diluted to a dry matter content of 14% by mass, based on the total mass of the diluted sediments, with process water containing less than 12% dry matter by mass, based on the total mass of the water.

[0147] The starch and fiber suspension is separated on 4 stages of 2 centrifugal rotary sieves, each equipped with a screen with perforations corresponding to 125pm by 1500pm slots.

[0148] Process water is used on each stage to dilute the residues and allow the suspension to be conveyed onto the sieve cloth.

[0149] The process water feeds in a counter-current flow to the 4th ème centrifugal rotary sieve stage is water having a dry matter of 0.8% by mass, and containing 0.25% by mass of starch and an N6.25 content of 0.12% by mass, based on the total mass of water.

[0150] The refusal stemming from the 4th ème The stage is concentrated by passing through a centrifugal decanter in order to obtain wet pulps (aqueous composition of fiber extracted from tuber) having a dry matter of 18% by mass, based on the total mass of the pulp.

[0151] 5T / h of wet pulp (aqueous composition of fiber extracted from tuber) obtained previously are mixed with 1.67T / h of dried fiber (powdered composition) in a twin-shaft paddle mixer to obtain an aqueous mixture of fiber extracted from tuber in the form of a friable product having a dry matter of 36% by mass, based on the total mass of the product.

[0152] The drying stage is carried out using a Flash type pneumatic dryer. The mixture is fed into a rotating disperser in a stream of hot air and conveyed within a drying tube.

[0153] The inlet temperature of the dryer is 280°C and the outlet temperature is 103°C.

[0154] At the outlet of the dryer, 1 T / h of fiber powder with a dry matter of approximately 90% by mass, based on the total mass of the powder, is obtained.

[0155] [Table 1]

[0156] From the fiber coming out of the dryer, an additional sieving step is carried out to make 2 batches: batch A is obtained by sieving on a vibrating sieve equipped with a 500pm screen and batch B is obtained by sieving on a vibrating sieve equipped with a 2mm screen.

[0157] Other batches C and D are also manufactured using a process similar to that of batch B. The properties of the fibers obtained using the methods detailed in the description are summarized in the table below. The "CAH" column corresponds to the oil absorption capacity (g of oil / g of powder). The "CH" column corresponds to the hydration capacity (g of water / g of powder). It should be noted that the method described above for obtaining the hydration capacity corresponds to that of US patent 2008 / 0226807.

[0158] [Table 2}

[0159] The fibers from these batches A to D have a high dietary fiber content. Tests have demonstrated that the invention makes it possible to produce a potato fiber powder with excellent hydration and oil absorption properties.

[0160] Example 2: Fiber production including a step of drying wet pulp from a wet / dry mixture of 1 / 0.33

[0161] 80 tons per hour of pre-washed potatoes are fed into four industrial graters, each equipped with a 400 mm diameter drum. 0.8 liters per hour of a 39% (mass) sodium bisulfite solution are introduced at the grater. The resulting grated potato has a dry matter content of 24.3% (mass), based on the total mass of the grated potato.

[0162] This grated material then feeds into centrifugal decanters to obtain solid sediments containing mainly starch and fiber with a dry matter content of 43% by mass, based on the total mass of the sediments.

[0163] The sediments are then diluted to a dry matter of 20% by mass based on the total mass of the diluted sediments, with process waters of which the dry matter is less than 12% by mass, based on the total mass of the waters.

[0164] The starch and fiber suspension is separated on 4 stages of 2 centrifugal rotary sieves, each equipped with a screen with perforations corresponding to 125pm by 1500pm slots.

[0165] Process water is used on each stage to dilute the residues and allow the suspension to be conveyed onto the screen. The process water feeds counter-currently to the 4th èmecentrifugal rotary sieve stage is water having a dry matter of 0.8% by mass and containing 0.25% by mass of starch and an N6.25 content of 0.12% by mass, based on the total mass of water.

[0166] The refusal stemming from the 4th ème The stage is concentrated by passing through a centrifugal decanter in order to obtain wet pulps (aqueous composition of fiber extracted from tuber) having a dry matter of 19% by mass, based on the total mass of the pulps.

[0167] 4.63T / h of wet pulp (aqueous composition of fiber extracted from tuber) obtained previously are mixed with 1.57T / h of dried fiber (powdered composition) in a twin-shaft paddle mixer to obtain an aqueous mixture of fiber extracted from tuber in the form of a friable product having a dry matter of 36.5% by mass, based on the total mass of the product.

[0168] The drying stage is carried out using a Flash type pneumatic dryer. The mixture is fed into a rotating disperser in a stream of hot air and conveyed within a drying tube.

[0169] The inlet temperature of the dryer is 280°C and the outlet temperature is 101°C.

[0170] At the outlet of the dryer, 1 T / h of fiber powder with a dry matter of approximately 90% by mass, based on the total mass of powder, is obtained.

[0171] [Table 3]

[0172] From the fiber coming out of the dryer, an additional sieving step is carried out on a vibrating screen equipped with a 2mm screen.

[0173] The properties of the resulting fiber are grouped in the table below.

[0174] [Table 4]

[0175] The test demonstrated that it was possible, thanks to the invention, to provide a potato fiber powder with excellent hydration capacity and oil absorption capacity properties, close to those of batches A to D. This demonstrates that, even when the potato fiber content is lower, it is possible to obtain the fibers of the invention.

[0176] Example 3 (comparative): Drying of wet pulps from a wet / dry mixture of 1 / 1.05

[0177] This trial replicates the findings of US patent 2008 / 0226807. 80 tons per hour of pre-washed potatoes are fed into four industrial graters, each equipped with a 400 mm diameter drum. 0.8 L / h of a 39% (w / w) sodium bisulfite solution is introduced at the grater. The resulting grated potato has a dry matter content of 24.3% (w / w), based on the total mass of the grated potato.

[0178] This grated material then feeds into centrifugal decanters to obtain solid sediments containing mainly starch and fiber with a dry matter content of 43% by mass, based on the total mass of the sediments.

[0179] The sediments are then diluted to a dry matter of 14% by mass, based on the total mass of the diluted sediments, with process waters having a dry matter equal to or less than 12% by mass, based on the total mass of the waters.

[0180] The starch and fiber suspension is separated on 4 stages of 2 centrifugal rotary sieves, each equipped with a screen with perforations corresponding to 125pm by 1500pm slots.

[0181] Process water is used on each stage to dilute the residues and allow the suspension to be conveyed onto the sieve cloth.

[0182] The process water feeds in a counter-current flow to the 4th èmeThe centrifugal rotary sieve stage is water with a dry matter content of 0.8% by mass and containing 0.25% by mass of starch and a nitrogen content of 0.12% by mass, based on the total mass of the water. The residue from the 4th stage ème The stage is concentrated by passing through a centrifugal decanter in order to obtain wet pulps (aqueous composition of fiber extracted from tuber) having a dry matter of 18% by mass, based on the total mass of the pulps.

[0183] 50kg / h of wet pulp (aqueous composition of fiber extracted from tuber) are mixed with 52.9kg / h of dried fiber (powdery composition), within a double shaft paddle mixer to obtain an aqueous mixture of fiber extracted from tuber in the form of a friable product having a dry matter of 55% by mass, based on the total mass of the product.

[0184] The drying stage is carried out using a pneumatic Flash Ring Dryer. The mixture is fed into a rotating disperser in a stream of hot air and conveyed within a drying tube.

[0185] The inlet temperature of the dryer is 167°C and the outlet temperature is 85°C.

[0186] At the outlet of the dryer, 10kg / h of fiber powder with a dry matter of approximately 90% by mass, based on the total mass of powder, is obtained.

[0187] Two samples are taken and analyzed:

[0188] [Table 5]

[0189] The products contain a significant proportion of agglomerates. The fibers are sieved on a vibrating screen equipped with a 2000 µm mesh to remove agglomerates and granular fibers.

[0190] [Table 6]

[0191] Thus, the teaching of document US 2008 / 0226807 makes it possible to obtain fibers with a relatively high hydration capacity, although lower than in batches A to E. However, it is also noted that these potato fibers have a significantly lower oil absorption capacity than those of the invention.

[0192] For illustrative purposes, the hydration and oil absorption capacities of tuber fiber powder G were determined using the methods described in Stanisic et al. A hydration capacity of 12.0 g / g was determined and an oil absorption capacity of 3.6 g / g.

[0193] This also confirms that the fiber powder evaluated in the publication by Stanisic et al. as having a hydration capacity of 9.5 g / g and, therefore, has a hydration capacity much lower than that of the comparative fibers of Example 3, and thus even lower than that of the tuber fibers of the invention (Examples 1 and 2).

[0194] All the tests demonstrated that it was possible with the invention to obtain tuber fibers that combined high hydration and oil absorption capacities. Several hypotheses could explain these differences, which are otherwise characterizable by its improved oil absorption and hydration capacities. These hypotheses could include the shape of the tuber fiber powder particles, which appear particularly elongated, and / or a density that may appear different, and / or the composition of the fiber powder.

[0195] Example 4 (comparative): Properties of commercial potato fibers

[0196] The table below shows the properties of potato fibers marketed by JRS: Vitacel KF150+ and Vitacel KF200+

[0197] [Table 7]

[0198] It is noted that all commercial potato fibers also exhibit a lower oil absorption capacity than those of the invention.

[0199] Example 5: Illustration of the benefits of the fibers of the invention in use as an alternative to meat

[0200] It is preferable when cooking a steak if it does not shrink during pan-frying. The shrinkage of a plant-based burger during cooking was evaluated in the following test.

[0201] The recipes used are as follows:

[0202] [Table 8]

[0203] For a 1500 gram batch of meat alternative

[0204] Binder production: Disperse the methylcellulose in the oil in a mixer, adding two-thirds of the water that has been previously stored in the refrigerator.

[0205] Production of hydrated protein: mix the protein for 30 minutes at room temperature with one-third of the remaining water.

[0206] Mix the binder with the hydrated protein in a mass ratio of 60% binder / 40% hydrated protein. Form burgers by hand, each weighing 30 grams.

[0207] Preheat for 6 minutes at 180°C in an oven at 50% relative humidity

[0208] Freeze

[0209] The surface area of ​​the burgers was determined before cooking. The burger was then cooked in a fan oven at 180°C for 15 minutes, turning it halfway through.

[0210] The surface area of ​​the burgers was determined after cooking.

[0211] Compared to the control burger, the burger according to the invention appears less greasy on the surface. Furthermore, the surface area is reduced by only 13% instead of 15%, demonstrating more reliable shrinkage during cooking.

[0212] Thus, in addition to the nutritional interest of the fibers of the invention, thanks to their excellent hydration capacity and oil absorption capacity, they are also of interest when used in plant-based burger-type products.

Claims

Demands

1. Tuber-extracted fiber powder comprising a tuber dietary fiber content determined according to AOAC method 985.29 of at least 30%, and characterized in that it has: - an oil absorption capacity, determined according to TEST A, ranging from 4.0 to 7.5 g of oil / g of powder; - a hydration capacity, determined according to TEST B, ranging from 10.0 to 20.0 g of water / g of powder.

2. Fiber powder extracted from tuber according to claim 1 characterized in that it has an apparent density ranging from 0.10 to 0.20 g / ml.

3. Tuber-extracted fiber powder according to any one of the preceding claims characterized in that it comprises a total amount of tuber dietary fiber in the tuber-extracted fiber equal to or greater than 40%, e.g., from 40 to 80%, determined according to method AOAC 985.

29.

4. Tuber fiber powder according to any one of the preceding claims characterized in that it comprises a total amount of tuber dietary fiber in the tuber fiber ranging from 40 to 68%, advantageously from 45 to 65%, preferably from 50 to 60%, determined according to method AOAC 985.

29.

5. Fiber powder extracted from tuber according to any one of the preceding claims characterized in that it has a size d50 greater than 330 pm, advantageously from 350 to 500 pm, preferably from 380 to 460 pm, this size d50 being determined in dry process by laser granulometry.

6. Fiber powder extracted from tuber according to any one of the preceding claims characterized in that it has a dry matter content equal to or greater than 80% by mass, advantageously ranging from 85 to 95% by mass, relative to the total mass of the powder.

7. Fiber powder extracted from tuber according to any one of the preceding claims characterized in that it has an oil absorption capacity, determined according to TEST A, ranging from 5.0 to 7.0 g of oil / g of powder, for example from 5.3 to 6.4 g of oil / g of powder.

8. Fiber powder extracted from tuber according to any one of the preceding claims characterized in that it has a hydration capacity, determined according to TEST B, ranging from 12.0 to 17.0 g of water / g of powder.

9. Fiber powder extracted from tuber according to any one of the preceding claims characterized in that the tuber is the potato.

10. A process for manufacturing tuber-extracted fiber powder according to any one of the preceding claims, characterized in that it comprises: - a step of supplying an aqueous mixture of fiber extracted from tuber having a dry matter content of 15 to 45% by mass, relative to the total mass of the aqueous mixture; - a drying step of the aqueous mixture to form a powdery composition in a pneumatic dryer supplied with hot air such that the temperature of the air exiting the dryer is between 80 and 120°C, in which at least one stage of disintegration of the aqueous mixture is carried out inside the dryer; - optionally a sieving step of the powdery composition obtained during the previous step using a sieve with a mesh size ranging from 500 to 2500 pm to separate on one side the agglomerates of particles and on the other the fiber powder extracted from tuber.

Images