Preparation method of agrocybe cylindracea solid-state fermentation aleurone layer nutrition powder and nutrition powder prepared by preparation method

Abstract

A preparation method of agrocybe cylindracea solid state fermentation aleurone layer nutrition powder comprises the following steps: (1) selecting wheat grains, peeling and milling to obtain a wheat aleurone layer component; (2) adding water into the aleurone layer prepared in the step (1), uniformly mixing, and sterilizing at 121 DEG C for 20 minutes to obtain a wheat aleurone layer solid-state fermentation culture medium; (3) activating a strain, inoculating the activated agrocybe cylindracea strain into the wheat aleurone layer solid-state fermentation culture medium prepared in the step (2), and culturing at 26 DEG C to obtain a fermentation substrate; and (3) drying and crushing the fermentation substrate prepared in the step (3), and sieving with a 60-mesh sieve to obtain the agrocybe cylindracea solid-state fermentation aleurone layer nutrition powder, so that the agrocybe cylindracea solid-state fermentation aleurone layer nutrition powder is more easily absorbed and utilized by a human body, has higher economic value, achieves the purpose of high-value utilization, and improves the efficacy of the nutrition powder.

Description

Technical Field

[0001] The invention relates to the technical field of biological fermented food, and in particular to a method for preparing aleurone nutrient powder produced by solid-state fermentation of Agrocybe aegerita and the nutrient powder prepared thereby. Background Art

[0002] A large number of nutritional epidemiological studies have shown that increasing the intake of whole grain foods can effectively reduce the incidence of obesity, type 2 diabetes, cardiovascular and cerebrovascular diseases and some cancers, and these health benefits are mainly attributed to the synergistic effects of bioactive components in wheat bran. The physiologically active components in wheat bran are not evenly distributed, but are enriched in the aleurone layer, mainly including dietary fiber, vitamins, minerals, proteins, phenolic substances, lignans and phytosterols. However, most of the bioactive substances in the aleurone layer are connected to lignin or other cell wall polymers, or are embedded in the matrix, resulting in extremely low bioaccessibility and further bioavailability of the bioactive components in the aleurone layer through the digestive tract. Based on the high nutritional richness of the aleurone layer and the extensive resources of wheat bran, releasing the bioactive components in the aleurone layer through scientific and effective processes is the key to achieving its high-value utilization.

[0003] Compared with chemical and enzyme treatment, fermentation of agricultural products and their processing by-products using recognized safe microorganisms is a feasible and safe method for releasing bioactive substances. Solid-state fermentation refers to a fermentation process containing a solid matrix in the absence of or almost no free water. This technology has a history of thousands of years in my country, such as the production of liquor and Shanxi vinegar. It has the advantages of simple process, low cost, mild conditions, no equipment restrictions, high unit volume production capacity, and low wastewater discharge. Since the 1970s, it has regained attention and has developed rapidly. Due to the low water content in the fermentation medium, fungi and yeast are the most commonly used microorganisms, and filamentous fungi have attracted widespread attention due to their strong ability to degrade lignocellulose and can use agricultural waste for growth and reproduction. During the fermentation process, agricultural waste can not only provide the nutrients needed for fungal growth, but also release active substances under the action of extracellular enzymes secreted by fungi, making the entire fermentation process "bidirectional".

[0004] Agrocybe aegerita belongs to the phylum Basidiomycetes, class Agaricaceae, order Agaricales, family Strophariaceae, genus Agaricus. It is a high-fiber, low-fat edible and medicinal fungus that is rich in amino acids and trace elements required by the human body, and contains polysaccharides with anti-cancer activity. Solid-state fermentation of Agrocybe aegerita is a common form of fermentation that utilizes the growth of its mycelium on a specific substrate to produce a variety of enzymes and active substances. Through solid-state fermentation, Agrocybe aegerita can secrete cellulase, hemicellulase, lignin-degrading enzyme, etc., effectively degrade complex organic matter, and release more nutrients and bioactive substances. With the continuous optimization and in-depth research of fermentation technology, the application prospects of Agrocybe aegerita in the health industry will be broader, bringing more benefits to people's health.

[0005] In summary, although the endosperm contains most of the active substances in whole-wheat foods, it is not conducive to the market promotion of the product due to problems such as poor taste and low bioavailability. Summary of the invention

[0006] Based on the problems or shortcomings existing in the prior art, the purpose of the present invention is to provide a method for preparing a nutrient powder of solid-state fermented aleurone layer of Agrocybe aegerita and the nutrient powder prepared therefrom, so as to obtain a nutrient powder with low production cost, simple and easy-to-obtain production process equipment, low anti-nutritional factors in the obtained product, high content of absorbable nutrients, and a flavor and taste that are deeply loved by consumers, thereby realizing high-value utilization of bran resources.

[0007] In order to achieve the above object, the present invention provides a tea tree agrocybe solid-state fermentation aleurone layer nutrient powder, and the preparation method of the tea tree agrocybe solid-state fermentation aleurone layer nutrient powder comprises the following steps: Selecting wheat grains, peeling, and milling to obtain wheat aleurone components; The aleurone layer obtained in step (1) is mixed with water and sterilized at 121° C. for 20 minutes to obtain a wheat aleurone layer solid fermentation medium; Activating the strains, inoculating the activated Agrocybe aegerita strains into the wheat aleurone solid fermentation medium prepared in step (2), and culturing at 26° C. to obtain a fermentation matrix; The fermentation matrix prepared in step (3) is dried, crushed and passed through a 60-mesh sieve to obtain Agrocybe aegerita solid-state fermentation aleurone nutrient powder.

[0008] As a further description of the above technical solution, the wheat endosperm in step (1) is a bran component obtained by peeling 3-5% of wheat grains and then separating them through a traditional flour-making method.

[0009] As a further description of the above technical solution, the aleurone solid fermentation medium in step (2) uses only un-crushed wheat aleurone with a natural pH.

[0010] Preferably, in step (2), the mass ratio of the endosperm to water is 1:1.5.

[0011] As a further description of the above technical solution, the activated strain in step (3) is to inoculate Agrocybe aegerita on a PDA solid plate culture medium, culture it at 26°C for 9 days, and put it into use after activating it for more than 3 generations.

[0012] As a further description of the above technical solution, the inoculation of Agrocybe aegerita spawn in step (3) is achieved as follows: selecting activated Agrocybe aegerita spawn in good growth state, punching holes at the edge of the hyphae to obtain a mushroom block with an inner diameter of 15 mm, picking up the mushroom block with an inoculation needle, and evenly inoculating the hyphae downward on the endosperm culture medium.

[0013] Preferably, the solid-state fermentation time in step (3) is 12 days.

[0014] As a further description of the above technical solution, the drying temperature in step (4) is 60° C. and the drying time is 24 h.

[0015] The present invention also includes nutrient powder prepared by adopting the method for preparing nutrient powder of aleurone layer from solid-state fermentation of Agrocybe aegerita.

[0016] The present invention also provides application of the Agrocybe aegerita solid-state fermented aleurone layer nutrient powder in preparing food.

[0017] The endosperm layer contains abundant bioactive substances, most of which are covalently bound to biomacromolecules such as cellulose, lignin and protein, and can provide abundant nutrients for the growth and reproduction of Agrocybe aegerita, and is an excellent matrix for solid-state fermentation. Agrocybe aegerita mycelium can transform nutrients through its own metabolic activities to produce substances with a variety of biological activities, which have antioxidant, immunomodulatory, antibacterial and antiviral effects. The fruiting body is formed by highly twisted mycelium, so the nutritional value and effective components of the mycelium are highly similar to those of the fruiting body. Therefore, the solid-state fermentation endosperm layer nutrient powder of Agrocybe aegerita can degrade the macromolecules in the endosperm layer and release bioactive components while maintaining the efficacy of edible fungi.

[0018] The beneficial effects of the present invention include at least: (1) The content of phytic acid, an anti-nutritional factor, in the aleurone layer nutrient powder of the solid-state fermentation of Agrocybe aegerita is reduced, and the content and bioavailability of the active ingredients in the aleurone layer are increased through fermentation. During the solid-state fermentation process, Agrocybe aegerita secretes cellulase, xylanase, lignin degrading enzyme, ferulic acid esterase and phytase. Compared with the initial stage of fermentation, the enzyme activity increases by about 4-33 times. These enzymes can hydrolyze ether bonds, ester bonds or glycosidic bonds, degrade the fermentation substrate into small molecules, release bioactive ingredients, and make them easier to be absorbed and utilized by the human body.

[0019] (2) The tea tree mushroom solid-state fermentation aleurone layer nutrient powder of the present invention has a reduced lignocellulose content, an increased soluble solid content of 84.62%, an increased water holding capacity of 35.12%, and an increased total antioxidant capacity of 35.48%. While reducing the rough taste of the aleurone layer and improving consumer sensory acceptance, the antioxidant and anti-glycemic effects of the nutrient powder are enhanced, achieving the purpose of high-value utilization.

[0020] (3) The raw materials and preparation method of the present invention are simple, and since the water content of the fermentation matrix is ​​low, the risk of bacterial contamination can be minimized, and it is suitable for industrial production. In addition, the nutritional powder prepared by this method has a wide range of applications and can be added back into flour for making noodles, biscuits, steamed buns, bread, cakes, etc., and has high economic value.

[0021] (4) The cultivation technology of Agrocybe aegerita fruiting bodies is complicated and time-consuming, resulting in high product costs. Agrocybe aegerita fruiting bodies are formed by highly twisted mycelium, and the chemical composition and effective components of the mycelium are highly similar to those of the fruiting bodies. Therefore, the solid-state fermentation of Agrocybe aegerita can not only retain the biologically active components and unique flavor of edible fungi, but also synergize with the active components in the aleurone layer to improve the efficacy of the nutrient powder. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The growth status of mycelium of Agrocybe aegerita in the solid-state fermentation process in the embodiment of the present invention; Figure 2 The figure shows the changes in enzyme activity during the solid-state fermentation of Agrocybe aegerita in the embodiment of the present invention. DETAILED DESCRIPTION

[0023] In order to better understand the present invention, the present invention is further described and illustrated below in conjunction with examples, but the embodiments of the present invention are not limited thereto. Example

[0024] A method for preparing aleurone nutrient powder from solid-state fermentation of Agrocybe aegerita, the preparation steps being as follows: (1) Wheat kernels were first dehulled to 4% using a dehulling machine and then separated into the aleurone layer using a traditional milling method.

[0025] (2) The aleurone layer and water are uniformly mixed in a mass ratio of 1:1.5, with a natural pH value and without other auxiliary materials or additives, and sterilized at 121° C. for 20 minutes to obtain a wheat aleurone layer solid fermentation medium.

[0026] (3) The Agrocybe aegerita slant strain was activated and inoculated into PDA solid plate culture medium (short for Potato Dextrose Agar (Medium)), cultured at 26°C for 9 days, and put into use after being activated for more than 3 generations.

[0027] (4) Select the activated Agrocybe aegerita strain with good growth status, punch holes at the edge of the hyphae to obtain mushroom blocks with an inner diameter of 15 mm, pick up the mushroom blocks with an inoculation needle, and evenly inoculate the hyphae downward on the endosperm culture medium. Inoculate 15 mushroom blocks for every 300 g of fermentation medium. Culture at 26°C for 12 days to obtain the fermentation medium.

[0028] (5) The fermentation matrix is ​​dried at 60°C for 24 h, crushed after drying, and passed through a 60-mesh sieve to obtain the tea tree agrocybe solid-state fermentation aleurone nutrient powder. The physical and chemical properties are tested, and the powder is packaged in a sealed bag. The powder can be used to make nutrient powder products, including but not limited to noodles, biscuits, steamed buns, bread, and cakes.

[0029] Test Example 1 The growth of Agrocybe aegerita in the solid-state fermentation process in Example 1 was tested, including biomass and cellulose, hemicellulose, laccase and feruloyl esterase activities. The results were as follows: Figure 1 and Figure 2 shown.

[0030] Depend on Figure 1 It can be seen that as the fermentation time continues, the hyphae of Agrocybe aegerita expand outward in a circular shape. Within 6 days after inoculation, the hyphae are in the early stage of germination, and white filamentous hyphae are generated. By the 12th day, the hyphae have basically covered the surface of the fermentation matrix, and it can be seen from the cross-section that the hyphae have penetrated to the bottom of the fermentation matrix. From the internal diagram, it can be seen that the hyphae have basically wrapped the entire fermentation matrix. After 12 days, the growth rate of the hyphae began to slow down, and the fermentation matrix changed from a loose state to a compact or even hardened state. At the same time, small water droplets appeared on the surface of the hyphae, which may be due to the vigorous respiration of the Agrocybe aegerita during its growth.

[0031] like Figure 2As shown in the figure, during the solid-state fermentation of Agrocybe aegerita, the overall cellulase activity showed a trend of first increasing and then decreasing. In the early stage of fermentation, the enzyme activity gradually increased, which promoted the decomposition of cellulose and the release of phenolic and flavonoid substances; in the middle stage, the enzyme activity reached a peak, and the cellulose degradation efficiency was the highest; in the late stage, the enzyme activity decreased, which may be affected by substrate exhaustion and metabolite accumulation. The xylanase activity showed a trend of first increasing and then decreasing during the solid-state fermentation of Agrocybe aegerita. In the early stage of fermentation, the xylanase activity was low. As the strain gradually adapted, the xylanase activity gradually increased; in the middle stage of fermentation, the metabolic activity of the strain was the most active, and the highly active xylanase rapidly degraded xylan, releasing a large amount of available sugar substances. In this stage, the xylanase activity increased significantly, reaching a maximum of 10.00 U / g; in the late stage of fermentation, xylan had been largely degraded, and the remaining xylan was not enough to maintain a high level of enzyme activity. At the same time, the accumulation of metabolites may inhibit the activity of the enzyme, resulting in a decrease in xylanase activity. As the fermentation process progresses, the activity of laccase gradually increases, and the degradation and modification of lignin and phenolic compounds accelerate. The oxidation of laccase on lignin is significantly enhanced, generating a large amount of modified lignin and simple phenolic compounds, while releasing more cellulose and hemicellulose. In the early stage of fermentation, the activity of feruloyl esterase gradually increases, first hydrolyzing ferulic acid ester to release free ferulic acid, and gradually destroying the plant cell wall structure, promoting the action of other degrading enzymes. In the middle stage of fermentation, the enzyme activity reaches a peak, ferulic acid ester is decomposed in large quantities, and the concentration of free ferulic acid increases significantly. At the same time, the decomposition of the cell wall further promotes the degradation of cellulose and xylan, releasing a large amount of sugar substances for the use of Agrocybe aegerita strains, supporting their rapid growth and metabolic activities.

[0032] Test Example 2 The nutritional components of the tea tree mushroom solid-state fermentation aleurone layer nutrient powder prepared in Example 1 were detected, and the untreated aleurone layer was used for comparison, and its physical and chemical properties were measured at the same time, and the results are shown in Table 1. The soluble solids content of the aleurone layer before and after fermentation was 13% and 24%, respectively, the water holding capacity was 1.68 g / g and 2.27 g / g, respectively, the phytic acid content was 74.80 mg / g and 60.89 mg / g, respectively, and the total antioxidant capacity was 29.17 mmol TE / kg and 39.52 mmol TE / kg, respectively.

[0033] Table 1 Comparison of basic nutritional components between aleurone layer and nutrient powder The starch and fat contents in the solid-state fermented aleurone layer nutritional powder of Agrocybe aegerita decrease, while the protein and ash contents increase. This is because Agrocybe aegerita decomposes starch and fat during the fermentation process to provide energy for its growth and metabolic activities, and Agrocybe aegerita is a high-dietary fiber, low-fat edible and medicinal fungus that is rich in amino acids and trace elements required by the human body, thereby increasing the protein and ash contents in the nutritional powder. Therefore, the nutritional powder of the present invention is rich in amino acids and trace elements required by the human body while having low starch and fat contents, and has good practical value and promotion space.

[0034] As shown in Table 1, the soluble solid content in the nutrient powder increased after fermentation, and the water holding capacity was enhanced. This may be because the lignin degrading enzymes secreted by the tea tree mushroom destroyed the cell wall structure of the aleurone layer, and the long chains of cellulose and hemicellulose were broken, which increased the specific surface area and porosity, and helped the water to fully contact and penetrate the fiber interior. Good water holding capacity helps to improve the hydration capacity of the nutrient powder, thereby increasing the viscosity of the food. In addition, strong hydrophilicity helps defecation, thereby effectively preventing constipation and colon cancer.

[0035] Phytic acid can combine with protein, starch and minerals in bran, thereby changing the solubility of these nutrients, resulting in a decrease in their functionality, digestibility and absorption characteristics. As can be seen from Table 1, after solid-state fermentation, the phytic acid content in the nutritional powder decreased by 18.60%. The ortho-phenolic hydroxyl groups of phenolic substances give polyphenols strong antioxidant and free radical scavenging abilities, which can reduce inflammatory responses and blood clot formation, thereby playing a role in preventing cardiovascular diseases. Compared with the aleurone layer, the total phenol content and antioxidant capacity of the nutritional powder increased by 9.27% ​​and 35.48%, respectively.

[0036] In summary, the nutritional powder of the present invention has simple ingredients, low anti-nutritional factor content, high absorbable nutrient content, and its flavor and taste are deeply loved by consumers. In addition, the preparation method is simple, the raw material price is low, and it is easy to industrialize production, so it has good practical value and promotion space.

[0037] The above embodiment is only one of the specific implementation methods selected by the present invention, so the application of the present invention is not limited to the above examples. The usual changes and substitutions made by those skilled in the art within the scope of this technical solution should fall within the protection scope of the claims attached to the present invention.

Claims

1. A method for preparing tea tree mushroom solid-state fermentation aleurone nutrient powder, characterized in that: The following steps are involved: Selecting wheat grains, peeling, and milling to obtain wheat aleurone components; The aleurone layer obtained in step (1) is mixed with water and sterilized at 121° C. for 20 minutes to obtain a wheat aleurone layer solid fermentation medium; Activating the strains, inoculating the activated Agrocybe aegerita strains into the wheat aleurone solid fermentation medium prepared in step (2), and culturing at 26° C. to obtain a fermentation matrix; The fermentation matrix prepared in step (3) is dried, crushed and passed through a 60-mesh sieve to obtain Agrocybe aegerita solid-state fermentation aleurone nutrient powder.

2. The method for preparing the tea tree agrocybe solid-state fermentation aleurone nutrient powder according to claim 1, characterized in that: The wheat endosperm in step (1) is a bran component obtained by peeling 3-5% of wheat grains and then separating them through a traditional flour-making method.

3. The method for preparing the tea tree agrocybe solid-state fermentation aleurone nutrient powder according to claim 1, characterized in that: The aleurone solid fermentation medium in step (2) uses only un-crushed wheat aleurone with a natural pH.

4. The method for preparing the tea tree agrocybe solid-state fermentation aleurone nutrient powder according to claim 1, characterized in that: In step (2), the mass ratio of the endosperm to water is 1:1.

5.

5. The method for preparing the tea tree agrocybe solid-state fermentation aleurone nutrient powder according to claim 1, characterized in that: The activated strain in step (3) is obtained by inoculating Agrocybe aegerita into a PDA solid plate culture medium, culturing at 26° C. for 9 days, and putting it into use after being activated for more than 3 generations.

6. The method for preparing the tea tree agrocybe solid-state fermentation aleurone nutrient powder according to claim 1, characterized in that: The inoculation of Agrocybe aegerita spawn in step (3) is achieved as follows: selecting activated Agrocybe aegerita spawn in good growth state, punching holes at the edge of the hyphae to obtain a mushroom block with an inner diameter of 15 mm, picking up the mushroom block with an inoculation needle, and evenly inoculating the hyphae downward on the aleurone culture medium.

7. The method for preparing the tea tree agrocybe solid-state fermentation aleurone nutrient powder according to claim 6, characterized in that: The solid-state fermentation time in step (3) is 12 days.

8. The method for preparing the tea tree agrocybe solid-state fermentation aleurone nutrient powder according to claim 1, characterized in that: The drying temperature in step (4) is 60°C and the drying time is 24 h.

9. A tea tree mushroom solid-state fermentation aleurone nutrient powder, characterized in that: The powder is prepared by the method for preparing the tea tree agrocybe solid-state fermentation aleurone layer nutrient powder as described in any one of claims 1 to 8.

10. The tea tree agrocybe solid-state fermentation aleurone nutrient powder according to claim 9, characterized in that: It also includes the application of Agrocybe aegerita solid-state fermentation aleurone nutrient powder in food preparation.

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