A process for preparing multiple nutritional ingredients from oats

Abstract

The present invention provides a process for preparing multiple nutrients from oats, relating to the technical field of oat deep processing. The process comprises the following steps: oat crushing, sieving, and obtaining oat bran; oat bran is extracted by supercritical extraction technology to obtain pretreated oat bran and extract, the extract is treated with a gradient membrane and ultrafiltered to obtain oat oil; the pretreated oat bran is extracted by a continuous segmented extraction device; one-stage protein extraction, two-stage glucan extraction, three-stage immobilized enzymatic hydrolysis, and four-stage filler decolorization are followed by entering a system balance tank, membrane separation, and concentration to obtain oat β-glucan. The present invention can simultaneously extract multiple nutrients such as oat β-glucan, oat protein, oat oil, etc., which makes up for the shortcomings of the prior art, has a high degree of automation, and saves energy and reduces emissions.

Description

Technical Field

[0001] The invention relates to the technical field of oat deep processing, and in particular to a process for preparing multiple nutritional components from oats. Background Art

[0002] Oats, a member of the genus Avena in the family Poaceae, are annual or perennial herbs. They offer a rich and comprehensive nutritional profile, boasting higher levels of protein, fat, vitamin E, dietary fiber, and minerals such as calcium, magnesium, iron, and phosphorus than other cereals. They have numerous benefits, including lowering blood lipids, cholesterol, blood pressure, and blood sugar, and providing antioxidant properties.

[0003] Oat protein is one of the main components of oats. It has the highest protein content among cereals and a balanced composition of essential amino acids, containing all eight essential amino acids. Its lysine content is higher than that of wheat and rice, which facilitates the absorption of other amino acids in the diet. It is also rich in tryptophan, making it highly nutritional and health-promoting. Traditional protein extraction methods use alkali dissolution and acid precipitation. However, alkali can alter the structure of some amino acids in the protein, leading to toxicity and food safety concerns. Alternatively, enzyme preparations can be used to break down impurities or degrade proteins into peptides. However, plant proteins are complex, and a single protease cannot fully degrade them. Consequently, protein extraction rates are low, hindering the full utilization of the raw materials.

[0004] Oats are rich in oat β-glucan, which regulates the three highs, improves the intestinal tract, and enhances immunity. When used in cosmetics, it improves skin tone, repairs damaged skin, moisturizes, and mitigates UV damage. Oat β-glucan is a non-starch polysaccharide found in the cell walls of the oat endosperm and aleurone layer. It is a high-molecular-weight polymer composed of monomeric β-D-pyranose glucose linked by β-(1-3) and β-(1-4) glycosidic bonds. The ratio of β-(1-3) to β-(1-4) glycosidic bonds in water-soluble β-glucans is 1:2.5-1:2.6, while the ratio in water-insoluble β-glucans is 1:4.2. β-glucan accounts for over 85% of the oat endosperm and aleurone cell walls. Most oat β-glucans have a molecular weight range of 10 kDa to 200 kDa.

[0005] In order to increase the solubility and dispersibility of oat beta-glucan, fermentation is generally used to reduce the molecular weight of oat beta-glucan, or to achieve it by the method of end group modification. Fermentation method (such as Chinese patent CN110305920A, Chinese patent CN104846031A) produces enzymes by fermenting oat raw materials through bacterial strains, and degrades oat beta-glucan by enzymes. The types of enzymes are difficult to control, and there are many miscellaneous enzymes that cannot specifically decompose glucans. At the same time, some proteins are also degraded. The fermentation liquid components produced by this method are complex, and the back end is difficult to purify, making it difficult to achieve the industrialization of high-content oat beta-glucan. The method of group modification (Chinese patent CN103772527A) can introduce many drugs with certain oxidation and corrosiveness, and the defect of inaccurate modification site selection makes it difficult to ensure the safety of the product, thereby limiting its use in cosmetics and food fields.

[0006] Existing records show that oat β-glucan, oat oil, and oat protein can be extracted separately through a single production line, making it difficult to simultaneously extract multiple components in one step. Traditional oil crop extraction is generally achieved through pressing, subcritical extraction, supercritical extraction, and organic solvent extraction. Oats are not suitable for pressing. Subcritical extraction and organic solvent extraction can cause heavy organic solvent residues. Supercritical extraction is more natural and environmentally friendly, but the equipment investment is relatively large, making it unsuitable for large-scale, low-value-added products.

[0007] Based on this, developing an oat extraction process that can simultaneously extract multiple nutrients such as oat β-glucan and oat protein is a research focus of researchers in this field and is of great significance. Summary of the Invention

[0008] In view of the above problems, the present invention provides a process for preparing multiple nutrients from oats, which saves energy and reduces emissions with high efficiency by continuously extracting multiple nutrients.

[0009] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0010] In one aspect, the present invention provides a process for preparing multiple nutritional components from oats, comprising the following steps:

[0011] S1: Oatmeal is crushed and sieved to obtain oat bran;

[0012] S2: Oat bran is extracted by supercritical extraction technology at 30-50°C to obtain pretreated oat bran and extract, and the extract is treated with gradient membrane and membrane ultrafiltration to obtain oat oil;

[0013] S3: The pretreated oat bran obtained in S2 is extracted by a continuous segmented extraction device, wherein the continuous segmented extraction device comprises five sections: protein extraction, glucan extraction, immobilized enzymatic hydrolysis, filler decolorization, and a system balancing tank;

[0014] S4: First-stage protein extraction: The pretreated oat bran obtained in S2 is mixed with a buffer solution, adjusted to pH 6.5-7.0 at a temperature of 40-55°C, and extracted for 1-1.5 hours to obtain an oat protein extract and first-stage extracted bran; the oat protein extract is purified to obtain oat protein;

[0015] S5: Secondary β-glucan extraction: The bran obtained in S4 is mixed with a solvent and stirred at 70-90° C. for 1-2.5 hours at a stirring rate of 100-150 r / min to obtain a crude oat β-glucan extract and bran after secondary extraction;

[0016] S6: Three-stage immobilized enzymatic hydrolysis: The composite enzyme is immobilized and packed with a diameter-to-height ratio of 1:12-18 to obtain a packing layer; the crude oat β-glucan extract obtained in S5 is cooled to 55-65°C and passed through the packing layer at a flow rate of 700-850 kg / h to obtain an enzymatic hydrolyzate;

[0017] S7: Four-stage filler decolorization: The enzymatic hydrolyzate obtained in S6 is decolorized by adsorption and enters the system balance tank for membrane separation and concentration to obtain oat β-glucan.

[0018] Preferably, in S1, the mesh number of the sieve is 40-90 mesh; further preferably, in S1, the mesh number of the sieve is 40-80 mesh.

[0019] Preferably, in S2, the pore size of the gradient membrane treatment is 1.2-1.5 μm; further preferably, in S2, the pore size of the gradient membrane treatment is 1.4 μm.

[0020] Preferably, in S2, the retention rate of the membrane ultrafiltration is 45-55 KDa; further preferably, in S2, the retention rate of the membrane ultrafiltration is 45-50 KDa.

[0021] Preferably, in S2, the membrane for membrane ultrafiltration is an inorganic ceramic membrane.

[0022] Preferably, in S3, the continuous segmented extraction equipment further comprises a front-end treatment (supercritical extraction equipment) and a matching membrane separation device.

[0023] Preferably, in S3, the five sections of protein extraction, glucan extraction, immobilized enzymatic hydrolysis, filler decolorization, and system balancing tank are designed in series.

[0024] Preferably, in S4, the buffer is sodium phosphate;

[0025] Preferably, in S4, the solid-liquid ratio of the pretreated oat bran to the buffer solution is 1:12-18 g / 100 mL; further preferably, in S4, the solid-liquid ratio of the pretreated oat bran to the buffer solution is 1:12-15 g / 100 mL.

[0026] Preferably, in S4, the purification is inorganic membrane separation purification;

[0027] Preferably, the cutoff of the inorganic membrane separation and purification is 90-110KDa; further preferably, the cutoff of the inorganic membrane separation and purification is 90-100KDa.

[0028] Preferably, in S5, the solid-liquid ratio of the bran obtained in S4 to the solvent is 1:18-22 g / 100 mL; further preferably, in S5, the solid-liquid ratio of the bran obtained in S4 to the solvent is 1:18-20 g / 100 mL.

[0029] Preferably, in S5, the solvent is water.

[0030] Preferably, in S5, the stirring time is 1.5-2 h; further preferably, in S5, the stirring time is 2 h.

[0031] Preferably, in S5, the bran after the second stage extraction is dried and used as feed.

[0032] Preferably, in S6, the complex enzyme comprises cellulase, pentosanase and xylanase.

[0033] Preferably, the mass ratio of the cellulase, pentosanase and xylanase is 3-5:4-6:7-9; further preferably, the mass ratio of the cellulase, pentosanase and xylanase is 4:5:8.

[0034] Preferably, the enzymatic activity of the cellulase is 18,000-25,000 u / g; further preferably, the enzymatic activity of the cellulase is 18,000-20,000 u / g.

[0035] Preferably, the enzymatic activity of the pentosanase is 8000-12000 u / g; further preferably, the enzymatic activity of the pentosanase is 8000-10000 u / g.

[0036] Preferably, the enzymatic activity of the xylanase is 180,000-220,000 u / g; further preferably, the enzymatic activity of the xylanase is 180,000-200,000 u / g.

[0037] Preferably, in S7, the adsorption decolorization filler is activated carbon.

[0038] Preferably, in S7, the cutoff of the membrane separation is 18-22 KDa; further preferably, in S7, the cutoff of the membrane separation is 18-20 KDa.

[0039] Preferably, in S7, the concentration is membrane concentration with a cut-off of 0.8-1.2 KDa; more preferably, the cut-off is 1 KDa.

[0040] Preferably, S7 further comprises the steps of drying and screening.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] 1. The present invention uses supercritical extraction technology to extract avenanthramides and oat oil from oat bran with carbon dioxide, extracts heat-sensitive substances at low temperature, and retains the effective ingredients of medicinal plants in the extract. In addition, substances with high boiling points, low volatility, and easy pyrolysis can be extracted at a temperature far below their boiling points to obtain oat oil rich in avenanthramides. The oat oil can be used as an antioxidant and antihistamine ingredient in cosmetics, and can also be used as a food, with certain efficacy.

[0043] 2. The protein extraction of the present invention adopts low-temperature extraction with a buffer solution, avoiding the use of acid and alkali, protecting the activity of the protein, and solving environmental problems.

[0044] 3. The enzymatic hydrolysis process of the present invention uses immobilized enzyme fillers, the enzyme preparation can be reused, and the degree of enzymatic hydrolysis can be controlled by flow rate. This reduces the number of enzyme inactivation steps and reduces the generation of heat-sensitive materials in the product.

[0045] 4. The present invention adopts a filler method in the decolorization process, changes the traditional method of adding, mixing and stirring, improves the decolorization efficiency, solves the problem of difficult removal of activated carbon at the back end, and the filler activated carbon can be reused.

[0046] 5. The multi-product separation of the present invention is mainly achieved through membrane separation equipment, which has high separation accuracy, high degree of automation, high efficiency and low energy consumption.

[0047] 6. The present invention can simultaneously extract multiple nutrients such as oat β-glucan, oat protein, oat oil, etc., which makes up for the shortcomings of the existing technology.

[0048] 7. The present invention uses few drugs in the whole process, and all additives are food-grade raw and auxiliary materials, which meet the food safety usage specifications; the raw material utilization rate is high, no waste is generated, and resources are used rationally; the amount of wastewater generated is small, and the COD, BOD and suspended solids content in the water are low, which is easy to handle. The wastewater can be fermented anaerobicly, and after aerobic fermentation, it can be separated by ultrafiltration membrane and filtered by reverse osmosis membrane to achieve wastewater recycling, solving the problem of water resource consumption and environmental protection.

[0049] 8. This independently developed continuous segmented extraction equipment boasts high continuity, enabling continuous feeding and extraction. This system reduces pipeline transportation and eliminates dead spots where liquids remain. The system is highly airtight, eliminating contact with air and preventing microbial contamination. The equipment enables continuous multi-component segmented extraction, enzymatic hydrolysis, and decolorization. In conjunction with membrane separation equipment, it achieves high purification and recovery rates, enhancing product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 This is a flow chart of equipment and process of the process of Example 1 of the present invention. DETAILED DESCRIPTION

[0051] In order to make the technical means, creative features, purpose and effect of the present invention easy to understand, the present invention is further illustrated below in conjunction with specific embodiment, but the following embodiment is only a preferred embodiment of the present invention, not all. Based on the embodiment in the embodiment, other embodiments obtained by those skilled in the art without making creative work all fall within the protection scope of the present invention. It is worth noting that the raw materials used in the present invention are all common commercial products, and their source is not specifically limited. The technology and scientific terms used in the embodiment have the meaning commonly understood by those of ordinary skill in the art to which the present invention belongs.

[0052] Example 1

[0053] A process for preparing multiple nutritional components from oats comprises the following steps:

[0054] S1: Grind the oats, sieve them, and take oat bran with a mesh size of 60.

[0055] S2: Oat bran pretreatment: The sieved oat bran is subjected to supercritical extraction technology at a controlled extraction temperature of 40°C. Avenanthramides and oat oil in the oat bran are extracted using carbon dioxide to obtain pretreated oat bran and extract.

[0056] The extract is processed through a 1.4μm gradient membrane to remove some protein and starch, while also achieving a sterilization effect. It is then ultrafiltered through a 50KDa inorganic ceramic membrane to obtain oat alkaloid-rich oat oil.

[0057] S3: The pretreated oat bran obtained in S2 is Figure 1 The continuous segmented extraction equipment shown in the figure comprises five sections: protein extraction, glucan extraction, immobilized enzymatic hydrolysis, filler decolorization, and system balance tank.

[0058] S4: One-stage protein extraction: The pretreated oat bran was mixed with sodium phosphate buffer at a solid-liquid ratio of 1:15 g / 100 mL. The extraction temperature was controlled at 48°C and the pH was adjusted to 6.5-7.0. The oat bran was extracted for 1 hour and then solid-liquid separation was performed using the separation equipment provided by the equipment to obtain the oat protein extract and the bran after the first stage extraction.

[0059] The oat protein extract is separated and purified by a 100KDa inorganic membrane and then dried by a low-temperature spray drying tower to obtain an oat protein product with a protein content of 60-80%. The low-temperature extraction retains the natural activity of the protein and does not use alkali or acid, thus effectively solving environmental protection issues.

[0060] S5: Secondary β-glucan extraction: The bran after primary extraction enters the secondary extraction process of the equipment and is mixed with water. It is stirred at high speed for 2 hours at a speed of 120 r / min, a material-liquid ratio of 1:20 g / 100 mL, and a temperature of 80°C to fully dissolve the oat β-glucan in the extract, thereby obtaining a crude oat β-glucan extract and bran after secondary extraction. The crude oat β-glucan extract enters the third enzymatic hydrolysis reaction process, and the bran is separated and extruded by the equipment. After drying, it can be used as feed.

[0061] S6: Three-stage immobilized enzymatic hydrolysis: Using an immobilized enzyme filling design, 20,000 u / g of cellulase, 10,000 u / g of pentosanase, and 200,000 u / g of xylanase were compounded in a ratio of 4:5:8, and then the composite enzyme was immobilized by a porous ceramic material for filling, with a controlled diameter-to-height ratio of 1:15 to obtain an enzyme preparation filling layer.

[0062] The crude oat β-glucan extract was cooled to 63°C through a heat exchanger, with a flow rate controlled at 800 kg / h, and passed through an enzyme preparation filler layer.

[0063] S7: Four-stage filler decolorization: The enzymatic hydrolyzate obtained in S6 passes through the activated carbon filler layer for decolorization and adsorption. The refined extract enters the system balance tank, where it is separated from oat β-glucan by a 20KDa polyethersulfone organic membrane and concentrated by a 1KDa nanofiltration membrane. The finished product is spray-dried at low temperature, sieved, packaged, and stored.

[0064] Example 2

[0065] A process for preparing multiple nutritional components from oats comprises the following steps:

[0066] S1: Grind the oats, sieve them, and take oat bran of 80 mesh size.

[0067] S2: Oat bran pretreatment: The sieved oat bran is subjected to supercritical extraction technology at a controlled extraction temperature of 30°C. Avenanthramides and oat oil in the oat bran are extracted using carbon dioxide to obtain pretreated oat bran and extract.

[0068] The extract is processed through a 1.4μm gradient membrane to remove some protein and starch, while also achieving a sterilization effect. It is then ultrafiltered through a 45kDa inorganic ceramic membrane to obtain oat alkaloid-rich oat oil.

[0069] S3: The pretreated oat bran obtained in S2 is Figure 1 The continuous segmented extraction equipment shown in the figure comprises five sections: protein extraction, glucan extraction, immobilized enzymatic hydrolysis, filler decolorization, and system balance tank.

[0070] S4: One-stage protein extraction: The pretreated oat bran was mixed with sodium phosphate buffer at a solid-liquid ratio of 1:12 g / 100 mL. The extraction temperature was controlled at 45°C and the pH was adjusted to 6.5-7.0. The oat bran was extracted for 1 hour and then solid-liquid separation was performed using the separation equipment provided by the equipment to obtain the oat protein extract and the bran after the first stage extraction.

[0071] The oat protein extract is separated and purified by a 90KDa inorganic membrane and then dried by a low-temperature spray drying tower to obtain an oat protein product with a protein content of 60-80%. The low-temperature extraction retains the natural activity of the protein and does not use alkali or acid, thus effectively solving environmental protection issues.

[0072] S5: Secondary β-glucan extraction: The bran after primary extraction enters the secondary extraction process of the equipment and is mixed with water. It is stirred at high speed for 1.5 hours at a speed of 120 r / min, a material-liquid ratio of 1:20 g / 100 mL, and a temperature of 75°C to fully dissolve the oat β-glucan in the extract, thereby obtaining a crude oat β-glucan extract and bran after secondary extraction. The crude oat β-glucan extract enters the third enzymatic hydrolysis reaction process, and the bran is separated and extruded by the equipment. After drying, it can be used as feed.

[0073] S6: Three-stage immobilized enzymatic hydrolysis: Using an immobilized enzyme filling design, 20,000 u / g of cellulase, 10,000 u / g of pentosanase, and 200,000 u / g of xylanase were compounded in a ratio of 3:6:9. The composite enzyme was then immobilized on a porous ceramic material for filling, with a controlled diameter-to-height ratio of 1:15 to obtain an enzyme preparation filling layer.

[0074] The crude oat β-glucan extract was cooled to 60°C through a heat exchanger, with a flow rate controlled at 800 kg / h, and passed through an enzyme preparation filler layer.

[0075] S7: Four-stage filler decolorization: The enzymatic hydrolyzate obtained in S6 passes through the activated carbon filler layer for decolorization and adsorption. The refined extract enters the system balance tank, where it is separated from oat β-glucan by a 20KDa polyethersulfone organic membrane and concentrated by a 1KDa nanofiltration membrane. The finished product is spray-dried at low temperature, sieved, packaged, and stored.

[0076] Example 3

[0077] A process for preparing multiple nutritional components from oats comprises the following steps:

[0078] S1: Grind the oats, sieve them, and take oat bran with a mesh size of 60.

[0079] S2: Oat bran pretreatment: The sieved oat bran is subjected to supercritical extraction technology at a controlled extraction temperature of 45°C. Avenanthramides and oat oil in the oat bran are extracted using carbon dioxide to obtain pretreated oat bran and extract.

[0080] The extract is processed through a 1.4μm gradient membrane to remove some protein and starch, while also achieving a sterilization effect. It is then ultrafiltered through a 55kDa inorganic ceramic membrane to obtain oat alkaloid-rich oat oil.

[0081] S3: The pretreated oat bran obtained in S2 is Figure 1 The continuous segmented extraction equipment shown in the figure comprises five sections: protein extraction, glucan extraction, immobilized enzymatic hydrolysis, filler decolorization, and system balance tank.

[0082] S4: One-stage protein extraction: The pretreated oat bran was mixed with sodium phosphate buffer at a solid-liquid ratio of 1:18 g / 100 mL. The extraction temperature was controlled at 50°C and the pH was adjusted to 6.5-7.0. The oat bran was extracted for 1 hour and then solid-liquid separation was performed using the separation equipment provided by the equipment to obtain the oat protein extract and the bran after the first stage extraction.

[0083] The oat protein extract is separated and purified by a 110KDa inorganic membrane and then dried by a low-temperature spray drying tower to obtain an oat protein product with a protein content of 60-80%. The low-temperature extraction retains the natural activity of the protein and does not use alkali or acid, thus effectively solving environmental problems.

[0084] S5: Secondary β-glucan extraction: The bran after primary extraction enters the secondary extraction process of the equipment and is mixed with water. It is stirred at high speed for 2 hours at a speed of 120 r / min, a material-liquid ratio of 1:20 g / 100 mL, and a temperature of 85°C to fully dissolve the oat β-glucan in the extract, thereby obtaining a crude oat β-glucan extract and bran after secondary extraction. The crude oat β-glucan extract enters the third enzymatic hydrolysis reaction process, and the bran is separated and extruded by the equipment. After drying, it can be used as feed.

[0085] S6: Three-stage immobilized enzymatic hydrolysis: Using an immobilized enzyme filling design, 20,000 u / g of cellulase, 10,000 u / g of pentosanase, and 200,000 u / g of xylanase were compounded in a ratio of 5:4:7. The composite enzyme was then immobilized on a porous ceramic material for filling, with a controlled diameter-to-height ratio of 1:15 to obtain an enzyme preparation filling layer.

[0086] The crude oat β-glucan extract was cooled to 65°C through a heat exchanger, with a flow rate controlled at 800 kg / h, and passed through an enzyme preparation filler layer.

[0087] S7: Four-stage filler decolorization: The enzymatic hydrolyzate obtained in S6 passes through the activated carbon filler layer for decolorization and adsorption. The refined extract enters the system balance tank, where it is separated from oat β-glucan by a 20KDa polyethersulfone organic membrane and concentrated by a 1KDa nanofiltration membrane. The finished product is spray-dried at low temperature, sieved, packaged, and stored.

[0088] Comparative Example 1

[0089] A process for preparing multiple nutritional components from oats comprises the following steps:

[0090] S1: Grind the oats, sieve them, and take the oat bran in the 60-mesh range.

[0091] S2: Oat bran pretreatment: The sieved oat bran is subjected to supercritical extraction technology, the extraction temperature is controlled at 65°C, and avenanthramides and oat oil in the oat bran are extracted by carbon dioxide to obtain pretreated oat bran and extract.

[0092] The extract is ultrafiltered through an inorganic ceramic membrane 50KDa to obtain oat oil rich in oat alkaloids.

[0093] S3: The pretreated oat bran obtained in S2 is Figure 1 The continuous segmented extraction equipment shown in the figure comprises five sections: protein extraction, glucan extraction, immobilized enzymatic hydrolysis, filler decolorization, and system balance tank.

[0094] S4: One-stage protein extraction: The pretreated oat bran was mixed with sodium phosphate buffer at a solid-liquid ratio of 1:10 g / 100 mL. The extraction temperature was controlled at 65°C and the pH was adjusted to 6.5-7.0. The oat bran was extracted for 1 hour and then solid-liquid separation was performed using the separation equipment provided by the equipment to obtain the oat protein extract and the bran after the first stage extraction.

[0095] The oat protein extract is separated and purified by a 100KDa inorganic membrane and then passed through a low-temperature spray drying tower to obtain an oat protein product with a protein content of 60-80%.

[0096] S5: Secondary β-glucan extraction: The bran after primary extraction enters the secondary extraction process of the equipment and is mixed with water. It is stirred at high speed for 2 hours at a speed of 120 r / min, a material-liquid ratio of 1:20 g / 100 mL, and a temperature of 95°C to fully dissolve the oat β-glucan in the extract, thereby obtaining a crude oat β-glucan extract and bran after secondary extraction. The crude oat β-glucan extract enters the third enzymatic hydrolysis reaction process, and the bran is separated and extruded by the equipment. After drying, it can be used as feed.

[0097] S6: Three-stage immobilized enzymatic hydrolysis: Using an immobilized enzyme filling design, 20,000 u / g of cellulase, 10,000 u / g of pentosanase, and 200,000 u / g of xylanase were compounded in a ratio of 4:5:8, and then the composite enzyme was immobilized by a porous ceramic material for filling, with a controlled diameter-to-height ratio of 1:15 to obtain an enzyme preparation filling layer.

[0098] The crude oat β-glucan extract was cooled to 55°C through a heat exchanger, with a flow rate controlled at 800 kg / h, and passed through an enzyme preparation filler layer.

[0099] S7: Four-stage filler decolorization: The enzymatic hydrolyzate obtained in S6 passes through the activated carbon filler layer for decolorization and adsorption. The refined extract enters the system balance tank, where it is separated from oat β-glucan by a 20KDa polyethersulfone organic membrane and concentrated by a 1KDa nanofiltration membrane. The finished product is spray-dried at low temperature, sieved, packaged, and stored.

[0100] Comparative Example 2

[0101] A process for preparing multiple nutritional components from oats comprises the following steps:

[0102] S1: Grind the oats, sieve them, and take the oat bran in the 60-mesh range.

[0103] S2: Oat bran pretreatment: The sieved oat bran is subjected to supercritical extraction technology, the extraction temperature is controlled at 40°C, and avenanthramides and oat oil in the oat bran are extracted by carbon dioxide to obtain pretreated oat bran and extract.

[0104] The extract is processed through a 1.4μm gradient membrane to remove some protein and starch, while also achieving a sterilization effect. It is then ultrafiltered through a 50KDa inorganic ceramic membrane to obtain oat alkaloid-rich oat oil.

[0105] S3: The pretreated oat bran obtained in S2 is Figure 1 The continuous segmented extraction equipment shown in the figure comprises five sections: protein extraction, glucan extraction, immobilized enzymatic hydrolysis, filler decolorization, and system balance tank.

[0106] S4: One-stage protein extraction: The pretreated oat bran was mixed with a mixed aqueous solution of sodium chloride and EDTA (mass ratio 10:1, the total concentration of sodium chloride and EDTA is 1%), with a solid-liquid ratio of 1:15 g / 100 mL, the extraction temperature was controlled at 48°C, the pH was adjusted to 6.5-7.0, and the equipment was used for one-stage extraction for 1 hour. The solid-liquid separation was performed using the equipment's own separation equipment to obtain the oat protein extract and the bran after one-stage extraction.

[0107] The oat protein extract is separated and purified by a 100KDa inorganic membrane and then dried by a low-temperature spray drying tower to obtain an oat protein product with a protein content of 60-80%. The low-temperature extraction retains the natural activity of the protein and does not use alkali or acid, thus effectively solving environmental protection issues.

[0108] S5: Secondary β-glucan extraction: The bran after primary extraction enters the secondary extraction process of the equipment and is mixed with the solvent. It is stirred at high speed for 2 hours at a speed of 120 r / min, a material-liquid ratio of 1:20 g / 100 mL, and a temperature of 80°C to fully dissolve the oat β-glucan in the extract, thereby obtaining a crude oat β-glucan extract and the bran after secondary extraction. The crude oat β-glucan extract enters the third enzymatic hydrolysis reaction process, and the bran is separated and extruded by the equipment. After drying, it can be used as feed.

[0109] S6: Three-stage immobilized enzymatic hydrolysis: Using an immobilized enzyme filling design, 20,000 u / g of cellulase, 10,000 u / g of pentosanase, and 200,000 u / g of xylanase were compounded in a ratio of 4:5:8, and then the composite enzyme was immobilized by a porous ceramic material for filling, with a controlled diameter-to-height ratio of 1:15 to obtain an enzyme preparation filling layer.

[0110] The crude oat β-glucan extract was cooled to 63°C through a heat exchanger, with a flow rate controlled at 800 kg / h, and passed through an enzyme preparation filler layer.

[0111] S7: Four-stage filler decolorization: The enzymatic hydrolyzate obtained in S6 passes through the activated carbon filler layer for decolorization and adsorption. The refined extract enters the system balance tank, where it is separated from oat β-glucan by a 20KDa polyethersulfone organic membrane and concentrated by a 1KDa nanofiltration membrane. The finished product is spray-dried at low temperature, sieved, packaged, and stored.

[0112] Comparative Example 3

[0113] A process for preparing multiple nutritional components from oats comprises the following steps:

[0114] Compared with Example 1, only the complex enzyme in S6 was changed to cellulase, and the total enzyme activity was consistent with that in Example 1. The rest of the operations were the same as those in Example 1.

[0115] Comparative Example 4

[0116] A process for preparing multiple nutritional components from oats comprises the following steps:

[0117] Compared with Example 1, only the complex enzyme in S6 was changed to pentosanase, and the total enzyme activity was consistent with that in Example 1. The rest of the operations were the same as those in Example 1.

[0118] Comparative Example 5

[0119] A process for preparing multiple nutritional components from oats comprises the following steps:

[0120] Compared with Example 1, only the complex enzyme in S6 was changed to xylanase, and the total enzyme activity was consistent with that in Example 1. The rest of the operations were the same as in Example 1.

[0121] Comparative Example 6

[0122] A process for preparing multiple nutritional components from oats comprises the following steps:

[0123] Compared with Example 1, only the complex enzyme in S6 was changed to cellulase and xylanase in a ratio of 4:8, and the total enzyme activity was consistent with that in Example 1. The rest of the operations were the same as in Example 1.

[0124] Comparative Example 7

[0125] A process for preparing multiple nutritional components from oats comprises the following steps:

[0126] Compared with Example 1, only the complex enzyme in S6 was changed to cellulase and pentosanase in a ratio of 4:5, and the total enzyme activity was consistent with that in Example 1. The rest of the operations were the same as in Example 1.

[0127] Comparative Example 8

[0128] A process for preparing multiple nutritional components from oats comprises the following steps:

[0129] Compared with Example 1, only the composite enzyme in S6 was changed to add a thermostable α-amylase to hydrolyze starch, and the total enzyme activity was consistent with that in Example 1. The rest of the operations were the same as in Example 1.

[0130] Comparative Example 9

[0131] A process for preparing multiple nutritional components from oats comprises the following steps:

[0132] Compared with Example 1, only the ratio of cellulase, pentosanase and xylanase in S6 was changed to 2:1:10. The rest of the operations were the same as in Example 1.

[0133] Test Example 1

[0134] The products obtained in the examples and comparative examples of the present invention were tested, and the test basis is as follows:

[0135] Oat β-glucan testing basis: NY / T2006-2011;

[0136] Protein detection according to: GB / T5009.5-2016;

[0137] Pentosan testing is based on: NY / T2335-2013;

[0138] Glucose testing is based on: GB / T5009.8-2023;

[0139] Avenanthramide detection basis: GB / T 36942-2018.

[0140] The products obtained in Examples 1-3 and Comparative Examples 1-9 were tested, as shown in Table 1:

[0141] Table 1. Nutrient content

[0142] As can be seen from the data in Table 1, the specific supercritical extraction technology of the present invention uses carbon dioxide to extract avenanthramides and oat oil from oat bran while separating them through a specific membrane. Then, a buffer solution is used to extract protein at low temperature, avoiding the use of acid and alkali, protecting the activity of the protein, and solving environmental problems. Through a specific enzymatic hydrolysis process, the immobilized enzyme filler is used to operate, so that the β-glucan in the oats is extracted efficiently. Although accompanied by a little pentosan with the effects of enhancing immunity, anti-oxidation, reducing inflammation, promoting intestinal health, and supporting cardiovascular health, the glucose (impurity) content is very low. The products of Examples 1-3 contain high levels of β-glucan, protein, and avenanthramide. Comparative Example 1 reduces β-glucan and increases glucose content by adjusting the extraction temperature; protein and avenanthramide content are reduced. Comparative Example 2 does not undergo a membrane separation step, and the buffer of S4 is also replaced. It can be seen that its protein and avenanthramide content is significantly reduced. Comparative Examples 3-9 mainly change the complex enzyme in S6, and its β-glucan content is significantly reduced and its glucose content is significantly increased.

[0143] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions of the technical solution of the present invention by ordinary technicians in this field do not deviate from the essence and scope of the technical solution of the present invention.

Claims

1. A process for preparing multiple nutritional ingredients from oats, characterized in that: The following steps are involved: S1: Oatmeal is crushed and sieved to obtain oat bran; S2: Oat bran is extracted by supercritical extraction technology at 30-50°C to obtain pretreated oat bran and extract, and the extract is treated with gradient membrane and membrane ultrafiltration to obtain oat oil; S3: The pretreated oat bran obtained in S2 is extracted by a continuous segmented extraction device, wherein the continuous segmented extraction device comprises five sections: protein extraction, glucan extraction, immobilized enzymatic hydrolysis, filler decolorization, and a system balancing tank; S4: First-stage protein extraction: The pretreated oat bran obtained in S2 is mixed with a buffer solution, adjusted to pH 6.5-7.0 at a temperature of 40-55°C, and extracted for 1-1.5 hours to obtain an oat protein extract and first-stage extracted bran; the oat protein extract solution is purified to obtain oat protein; the buffer solution is sodium phosphate; S5: Secondary β-glucan extraction: The bran obtained in S4 is mixed with a solvent and stirred at 70-90° C. for 1-2.5 hours at a stirring rate of 100-150 r / min to obtain a crude oat β-glucan extract and bran after secondary extraction; S6: Three-stage immobilized enzymatic hydrolysis: The composite enzyme is immobilized and packed with a diameter-to-height ratio of 1:12-18 to obtain a packing layer; the crude oat β-glucan extract obtained in S5 is cooled to 55-65°C and passed through the packing layer at a flow rate of 700-850 kg / h to obtain an enzymatic hydrolysis solution; the composite enzyme comprises cellulase, pentosanase, and xylanase; the mass ratio of the cellulase, pentosanase, and xylanase is 3-5:4-6:7-9; S7: Four-stage filler decolorization: The enzymatic hydrolyzate obtained in S6 is decolorized by adsorption and enters the system balance tank for membrane separation and concentration to obtain oat β-glucan.

2. The process according to claim 1, characterized in that In S1, the mesh size of the sieving is 40-90 meshes.

3. The process according to claim 1, characterized in that In S2, the pore size of the gradient membrane treatment is 1.2-1.5 μm; the retention capacity of the membrane ultrafiltration is 45-55 KDa.

4. The process according to claim 1, characterized in that In S3, the five sections of protein extraction, glucan extraction, immobilized enzymatic hydrolysis, filler decolorization, and system balance tank are designed in series.

5. The process according to claim 1, characterized in that In S4, the purification is inorganic membrane separation and purification; the cutoff of the inorganic membrane separation and purification is 90-110KDa.

6. The process according to claim 1, characterized in that The enzymatic activity of the cellulase is 18,000-25,000 u / g; the enzymatic activity of the pentosanase is 8,000-12,000 u / g; and the enzymatic activity of the xylanase is 180,000-220,000 u / g.

7. The process according to claim 1, characterized in that In S7, the filler for adsorption and decolorization is activated carbon; the cutoff of the membrane separation is 18-22 KDa; and the concentration is membrane concentration with a cutoff of 0.8-1.2 KDa.

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