Preparation method and application of pleurotus citrinopileatus fermented quinoa flour with high antioxidant activity

Abstract

The invention discloses a preparation method and application of pleurotus citrinopileatus fermented quinoa flour with high antioxidant activity. The method comprises the following steps: preparing a pleurotus citrinopileatus seed solution; preparing a quinoa culture medium; inoculating the pleurotus citrinopileatus seed solution into a chenopodium quinoa culture medium, adding sterile water at the same time, and fermenting in a dark place to obtain a fermentation product; and performing freeze-drying treatment on the fermentation product, and performing crushing and sieving to obtain the pleurotus citrinopileatus fermented quinoa flour. According to the method, the contents of protein, total sugar, lysine and total flavone in the quinoa and the antioxidant activity can be effectively improved, a foundation is laid for industrialized production of the quinoa with high contents of protein, total sugar, total flavone and lysine, and a theoretical basis is provided for commercially producing antioxidant related products by the quinoa in the future. The method has the advantages of low cost, simple process, easy realization of industrialized production and the like.

Description

Technical Field

[0001] The present invention relates to the field of biotechnology, and in particular to a preparation method and application of Pleurotus eryngii fermented quinoa powder with high antioxidant activity. Background Art

[0002] Quinoa (Chenopodium quinoa) is a cereal grain native to South America with high nutritional value. Quinoa is not only rich in protein and contains the nine essential amino acids required by the human body, but also contains functional ingredients such as total sugars, flavonoids (total flavonoids), dietary fiber, vitamins (B group, E) and various minerals (such as iron, calcium, magnesium, zinc), showing broad application prospects in functional foods. Among them, lysine, as one of the essential amino acids, plays an important role in promoting the intellectual development of young children, enhancing memory, maintaining acid-base balance, and participating in fat metabolism; flavonoids are closely related to antioxidant, anti-inflammatory, and antiviral effects. However, most of the existing research on quinoa focuses on the optimization of the extraction process of nutrients (such as total flavonoids), and there is less research on how to increase its total flavonoid and lysine content.

[0003] Therefore, developing a method to increase the content of lysine and total flavonoids in quinoa is an urgent problem to be solved. Summary of the Invention

[0004] The invention provides a preparation method of quinoa powder fermented with Pleurotus aviculare with high antioxidant activity. The method can effectively improve the content of protein, total sugar, lysine and total flavonoids and the antioxidant activity of quinoa, and obtain the quinoa powder fermented with Pleurotus aviculare with high protein, total sugar, total flavonoids and lysine content, high antioxidant activity, low water holding capacity, low oil holding capacity, high emulsification and high in vitro digestibility.

[0005] The present invention also provides quinoa powder fermented by Pleurotus aviculare. The quinoa powder fermented by Pleurotus aviculare is prepared by the preparation method of the quinoa powder fermented by Pleurotus aviculare with high antioxidant activity. Therefore, the quinoa powder fermented by Pleurotus aviculare has the advantages of high protein, total sugar, total flavonoids and lysine content, high antioxidant activity, low water holding capacity, low oil holding capacity, high emulsification and high in vitro digestibility.

[0006] The present invention also provides Pleurotus aviculare fermented quinoa powder produced by the method for preparing the above-mentioned Pleurotus aviculare fermented quinoa powder with high antioxidant activity, or the use of the above-mentioned Pleurotus aviculare fermented quinoa powder in improving the hardness and / or elasticity of protein foods. Research by the inventors has shown that the Pleurotus aviculare fermented quinoa powder prepared by this method can be used to prepare protein bars.

[0007] The present invention also provides a method for preparing quinoa powder fermented with Pleurotus eryngii having high antioxidant activity, and its use in culturing quinoa using the method. The inventors' research has shown that the quinoa powder fermented with Pleurotus eryngii prepared by this method has higher protein, total sugar, lysine, and total flavonoid contents, as well as higher antioxidant activity, than the quinoa powder prepared in Comparative Example 1. Therefore, this method can be used to cultivate quinoa.

[0008] A first aspect of the present invention provides a method for preparing Pleurotus eryngii fermented quinoa powder with high antioxidant activity, comprising:

[0009] The Pleurotus erythrorhizome is inoculated into a solid culture medium at an inoculum rate of 8% to 10% by volume, and cultured in the dark to obtain a solid strain.

[0010] Inoculating the solid strain into a liquid culture medium at an inoculum rate of 8% to 10% V / W, and performing stirring culture to obtain a Pleurotus eryngii seed liquid;

[0011] sterilizing the soaked quinoa to obtain a quinoa culture medium;

[0012] inoculating the Pleurotus eryngii seed liquid into the quinoa culture medium, adding sterile water, and fermenting in the dark to obtain a fermentation product;

[0013] The fermentation product is freeze-dried, crushed and sieved to obtain Pleurotus eryngii fermented quinoa powder.

[0014] The method for preparing the Pleurotus eryngii fermented quinoa powder with high antioxidant activity as described above, wherein the freeze-drying process sequentially includes a pre-freeze-drying process and a main freeze-drying process;

[0015] During the pre-freeze-drying process, the temperature is -45 to -30°C and the time is 1 to 3 hours.

[0016] The main freeze-drying process is carried out according to a freeze-drying program, which includes a first section, a second section, a third section, a fourth section, a fifth section, a sixth section, a seventh section, an eighth section and a ninth section that are executed in sequence. From the first section to the ninth section, the temperature is controlled and gradually increases.

[0017] In the method for preparing the Pleurotus eryngii fermented quinoa powder with high antioxidant activity as described above, the parameters of the freeze-drying process are specifically controlled as follows:

[0018] The first section: temperature -52 to -48°C, normal pressure, time 4 to 6 hours;

[0019] The second section: temperature -42 ~ -38 ° C, vacuum degree 22 Pa, time 2 ~ 4 hours;

[0020] The third section: temperature -32 ~ -28 ° C, vacuum degree 22 Pa, time 4 ~ 6 hours;

[0021] The fourth section: temperature -20 to -15°C, vacuum degree 22 Pa, time 2 to 5 hours;

[0022] The fifth section: temperature -12 to -8°C, vacuum degree 22 Pa, time 1 to 3 hours;

[0023] The sixth section: temperature -6 to -2°C, vacuum degree 22 Pa, time 1 to 3 hours;

[0024] Section 7: temperature 2-6°C, vacuum 10 Pa, time 6-10 hours;

[0025] Section 8: temperature 10-20°C, vacuum 10 Pa, time 3-5 hours;

[0026] Ninth section: temperature 25-35°C, vacuum degree 10 Pa, time 6-10 hours.

[0027] The preparation method of the Pleurotus eryngii fermented quinoa powder with high antioxidant activity as described above, wherein the soaked quinoa is sterilized to obtain a quinoa culture medium, specifically comprising: soaking 50-60 g of quinoa in water for 10-14 hours to obtain soaked quinoa, and then sterilizing the soaked quinoa at 110-130° C. for 20-30 minutes to obtain a quinoa culture medium.

[0028] The method for preparing the Pleurotus eryngii fermented quinoa powder with high antioxidant activity as described above, wherein the volume mass ratio of the Pleurotus eryngii seed liquid to the quinoa culture medium is (8-10 mL): (50-60 g dry weight);

[0029] And / or, the volume mass ratio of the sterile water to the quinoa culture medium is (8-10 mL): (50-60 g dry weight).

[0030] The method for preparing the Pleurotus eryngii fermented quinoa powder with high antioxidant activity as described above, wherein the temperature of the dark-proof culture is 25-28° C. and the time is 10-12 days;

[0031] And / or, the agitation culture temperature is 25-28°C, the rotation speed is 120-150 rpm, and the time is 10-12 days;

[0032] And / or, the temperature of the light-proof fermentation is 25-28° C., and the time is 20-22 days.

[0033] The method for preparing the Pleurotus quinoa fermented quinoa powder with high antioxidant activity as described above, wherein the quinoa is any one of black quinoa, white quinoa, and red quinoa;

[0034] And / or, the solid culture medium is potato dextrose agar medium, and the components and contents of the potato dextrose agar medium are as follows: potato extract powder 12 g / L, glucose 20 g / L, agar 14 g / L;

[0035] And / or, the liquid culture medium is composed of the following components in terms of weight to volume ratio g / mL: 30% potato juice, 4% glucose, 0.1% KH2PO4, 0.1% MgSO4·7H2O, and the remainder water.

[0036] A second aspect of the present invention provides quinoa powder fermented with Pleurotus aviculare, which is prepared by the method for preparing quinoa powder fermented with Pleurotus aviculare with high antioxidant activity.

[0037] The third aspect of the present invention provides Pleurotus aviculare fermented quinoa powder prepared by the method for preparing the Pleurotus aviculare fermented quinoa powder with high antioxidant activity, or the use of the Pleurotus aviculare fermented quinoa powder in preparing protein food.

[0038] A fourth aspect of the present invention provides an application of the method for preparing the Pleurotus ostreatus fermented quinoa powder with high antioxidant activity in quinoa cultivation, and culturing quinoa using the method.

[0039] The solution of the present invention has at least the following effects:

[0040] The present invention provides a method for preparing quinoa powder fermented with Pleurotus eryngii with high antioxidant activity. The method can effectively increase the protein, total sugar, lysine and total flavonoids contents and antioxidant activity in quinoa, lay a foundation for the factory production of quinoa with high protein, total sugar, total flavonoids and lysine contents, and provide a theoretical basis for the future use of quinoa in the commercial production of antioxidant-related products. The quinoa flour fermented with Pleurotus aviculare prepared by this method has high protein, total sugar, total flavonoids, and lysine content, high antioxidant activity, low water holding capacity, low oil holding capacity, high emulsification, and high in vitro digestibility. Low water holding capacity makes it easier for the quinoa flour fermented with Pleurotus aviculare to form a dry, crispy texture during processing (such as baking, frying, or puffing), making it suitable for developing snacks such as quinoa chips, cereal bars, and biscuits that require a crispy texture. Low oil holding capacity reduces the amount of oil absorbed by the quinoa flour fermented with Pleurotus aviculare during frying or pan-frying, making it suitable as a healthy breading (such as tempura and fried chicken substitutes), reducing the fat content of the final product and conforming to the trend of low-fat diets. High emulsification indicates that the quinoa flour fermented with Pleurotus aviculare is easier to emulsify and has potential application value in cosmetics and other fields. High in vitro digestibility is conducive to improving the utilization rate of nutrients in quinoa. This method has the advantages of low cost, simple process, and easy factory production.

[0041] The fermented quinoa powder of Pleurotus eryngii provided by the present invention has the advantages of high protein, total sugar, total flavonoids and lysine content, high antioxidant activity, low water holding capacity, low oil holding capacity, high emulsification and high in vitro digestibility, and has broad application prospects in the fields of food, cosmetics and the like. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0043] Figure 1 The water holding capacity test results and oil holding capacity test results of the quinoa powder fermented with Pleurotus eryngii in Example 1 of the present invention and the quinoa powder in Comparative Example 1;

[0044] Figure 2 These are the emulsification test results of the quinoa powder fermented with Pleurotus ostreatus in Example 1 of the present invention and the quinoa powder in Comparative Example 1. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with embodiments of the present invention. Obviously, the described embodiments are part of embodiments of the present invention, rather than all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. If specific techniques or conditions are not indicated in the embodiments, they are carried out according to the techniques or conditions described in the literature in this area or according to the product specifications. Reagents or instruments used that do not indicate manufacturers are conventional products that can be obtained commercially.

[0046] Quinoa contains nutrients such as protein, total sugars, flavonoids (total flavonoids), and lysine, and has broad applications in food, medicine, and beauty. However, existing research on quinoa has mostly focused on nutrient extraction, with less research on how to increase the content of nutrients (such as total flavonoids and lysine) in quinoa.

[0047] Based on this, the first aspect of the present invention provides a method for preparing Pleurotus eryngii fermented quinoa powder with high antioxidant activity, comprising:

[0048] The Pleurotus erythrorhizome is inoculated into a solid culture medium at an inoculum rate of 8% to 10% by volume, and cultured in the dark to obtain a solid strain.

[0049] Inoculating the solid strain into a liquid culture medium at an inoculum rate of 8% to 10% V / W, and performing stirring culture to obtain a Pleurotus eryngii seed liquid;

[0050] sterilizing the soaked quinoa to obtain a quinoa culture medium;

[0051] inoculating the Pleurotus eryngii seed liquid into the quinoa culture medium, adding sterile water, and fermenting in the dark to obtain a fermentation product;

[0052] The fermentation product is freeze-dried, crushed and sieved to obtain Pleurotus eryngii fermented quinoa powder.

[0053] The present invention does not particularly limit the specific particle size of the Pleurotus quinoa fermented quinoa powder obtained after the crushing and sieving, and can be selected according to actual needs.

[0054] The invention provides a preparation method for quinoa powder fermented with Pleurotus aviculare with high antioxidant activity. Specifically, Pleurotus aviculare strains are inoculated into a solid culture medium at an inoculum rate of 8% to 10% by volume, and cultured in the dark to activate the Pleurotus aviculare strains, thereby obtaining a solid strain; the solid strains are inoculated into a liquid culture medium at an inoculum rate of 8% to 10% by volume, and cultured with stirring to obtain a Pleurotus aviculare seed liquid, which is used for subsequent inoculation of a quinoa culture medium; the soaked quinoa is sterilized to obtain a sterile quinoa culture medium, which is conducive to the subsequent growth of Pleurotus aviculare mycelia in a sterile environment, that is, growth in the sterile quinoa culture medium; the Pleurotus aviculare seed liquid is inoculated into the quinoa culture medium, and sterile water is added, and fermentation is carried out in the dark to obtain a fermentation product; the fermentation product is freeze-dried, and crushed and sieved to obtain the Pleurotus aviculare fermented quinoa powder. The method provided by the present invention can improve the protein, total sugar, lysine and total flavonoids contents and antioxidant activity in quinoa; the quinoa powder fermented with Pleurotus ostreatus prepared by the method has the advantages of high protein, total sugar, total flavonoids and lysine contents, high antioxidant activity, low water holding capacity, low oil holding capacity, high emulsification and high in vitro digestibility.

[0055] In some embodiments, the freeze-drying process sequentially includes a pre-freeze-drying process and a main freeze-drying process;

[0056] During the pre-freeze-drying process, the temperature is -45 to -30°C and the time is 1 to 3 hours.

[0057] The main freeze-drying process is carried out according to a freeze-drying program, which includes a first section, a second section, a third section, a fourth section, a fifth section, a sixth section, a seventh section, an eighth section and a ninth section that are executed in sequence. From the first section to the ninth section, the temperature is controlled and gradually increases.

[0058] Specifically, the fermentation product is subjected to a pre-freeze-drying treatment and a main freeze-drying treatment in sequence to obtain a freeze-dried fermentation product, and then the freeze-dried fermentation product is crushed and sieved to obtain Pleurotus eryngii fermented quinoa powder.

[0059] The present invention first performs a pre-freeze-drying treatment on the fermentation product in order to form ice from the water in the fermentation product, and then performs a main freeze-drying treatment according to the freeze-drying procedure in order to sublime the ice into water vapor, thereby achieving efficient freeze-drying, thereby facilitating the acquisition of Pleurotus ostreatus fermented quinoa powder with high protein, total sugar, total flavonoids and lysine content, high antioxidant activity, low water retention, low oil retention, high emulsification and high in vitro digestibility.

[0060] In some embodiments, the parameters of the freeze-drying process are specifically controlled as follows:

[0061] The first section: temperature -52 to -48°C, normal pressure, time 4 to 6 hours;

[0062] The second section: temperature -42 ~ -38 ° C, vacuum degree 22 Pa, time 2 ~ 4 hours;

[0063] The third section: temperature -32 ~ -28 ° C, vacuum degree 22 Pa, time 4 ~ 6 hours;

[0064] The fourth section: temperature -20 to -15°C, vacuum degree 22 Pa, time 2 to 5 hours;

[0065] The fifth section: temperature -12 to -8°C, vacuum degree 22 Pa, time 1 to 3 hours;

[0066] The sixth section: temperature -6 to -2°C, vacuum degree 22 Pa, time 1 to 3 hours;

[0067] Section 7: temperature 2-6°C, vacuum 10 Pa, time 6-10 hours;

[0068] Section 8: temperature 10-20°C, vacuum 10 Pa, time 3-5 hours;

[0069] Ninth section: temperature 25-35°C, vacuum degree 10 Pa, time 6-10 hours.

[0070] When the main freeze-drying process is carried out according to the parameter control of the above-mentioned freeze-drying procedure, the ice is fully sublimated into water vapor, achieving more efficient freeze-drying, thereby obtaining Pleurotus ostreatus fermented quinoa powder with higher protein, total sugar, total flavonoids and lysine content, higher antioxidant activity, lower water holding capacity, lower oil holding capacity, higher emulsification and higher in vitro digestibility.

[0071] In some embodiments, the method of sterilizing the soaked quinoa to obtain the quinoa culture medium specifically comprises: soaking 50-60 g of quinoa in water for 10-14 hours to obtain soaked quinoa, and then sterilizing the soaked quinoa at 110-130° C. for 20-30 minutes to obtain the quinoa culture medium.

[0072] The water is of conventional type, for example, pure water.

[0073] In some embodiments, the volume-to-mass ratio of the Pleurotus quinoa seed solution to the quinoa culture medium is (8-10 mL): (50-60 g dry weight).

[0074] In some embodiments, the volume-to-mass ratio of the sterile water to the quinoa culture medium is (8-10 mL): (50-60 g dry weight).

[0075] In some embodiments, the temperature of the dark-proof culture is 25-28° C., and the time is 10-12 days.

[0076] Specifically, the Pleurotus ostreatus strain is inoculated into a solid culture medium at an inoculation rate of 8% to 10% V / W, and cultured in the dark at 25 to 28° C. for 10 to 12 days to obtain a solid strain.

[0077] In some embodiments, the agitation culture is carried out at a temperature of 25 to 28° C., a rotation speed of 120 to 150 rpm, and a time period of 10 to 12 days.

[0078] Specifically, the solid strain is inoculated into a liquid culture medium at an inoculation rate of 8% to 10% V / W, and cultured in the dark at 25 to 28° C. and 120 to 150 rpm for 10 to 12 days to obtain a Pleurotus eryngii seed liquid.

[0079] In some embodiments, the temperature of the light-proof fermentation is 25-28° C., and the fermentation time is 20-22 days.

[0080] Specifically, the Pleurotus quinoa seed liquid is inoculated into the quinoa culture medium, and sterile water is added, and fermented in the dark at 25-28° C. for 10-12 days to obtain a fermentation product. Sterile water, 25-28° C., and a dark environment provide necessary conditions for the growth of Pleurotus quinoa mycelium, and during the fermentation process under these conditions, the Pleurotus quinoa mycelium interacts with the quinoa to obtain a fermentation product.

[0081] In some embodiments, the quinoa is any one of black quinoa, white quinoa, and red quinoa, preferably black quinoa.

[0082] In some embodiments, the solid culture medium is potato dextrose agar medium, and the components and contents of the potato dextrose agar medium are as follows: 12 g / L potato extract, 20 g / L glucose, and 14 g / L agar.

[0083] In some embodiments, the liquid culture medium is composed of the following components in terms of weight to volume ratio g / mL: 30% potato juice, 4% glucose, 0.1% potassium dihydrogen phosphate (KH2PO4), 0.1% magnesium sulfate heptahydrate (MgSO4·7H2O), and the remainder water.

[0084] A second aspect of the present invention provides quinoa powder fermented with Pleurotus eryngii, which is prepared by the method for preparing quinoa powder fermented with Pleurotus eryngii with high antioxidant activity. Therefore, the quinoa powder fermented with Pleurotus eryngii has the advantages of high protein, total sugar, total flavonoids, and lysine content and high antioxidant activity, as well as low water and oil retention, high emulsification, and good in vitro digestibility.

[0085] A third aspect of the present invention provides Pleurotus aviculare fermented quinoa powder prepared by the method for preparing the above-mentioned Pleurotus aviculare fermented quinoa powder with high antioxidant activity, or the use of the above-mentioned Pleurotus aviculare fermented quinoa powder in preparing protein foods. Research by the inventors has shown that the Pleurotus aviculare fermented quinoa powder prepared by this method can be used to prepare protein bars.

[0086] A fourth aspect of the present invention provides an application of the method for preparing quinoa powder fermented with Pleurotus eryngii having high antioxidant activity in quinoa cultivation, wherein quinoa is cultivated using the method. Research by the inventors has shown that the protein, total sugar, lysine, and total flavonoids content, antioxidant activity, emulsification, and in vitro digestibility of the quinoa powder fermented with Pleurotus eryngii prepared by the method are significantly higher than those of unfermented quinoa, while its water and oil holding capacity are significantly lower than those of unfermented quinoa. Therefore, the method can be used to cultivate quinoa to increase the protein, total sugar, lysine, and total flavonoids content and antioxidant activity in quinoa.

[0087] The present invention is further described below through specific examples.

[0088] Example 1

[0089] This embodiment provides a method for preparing Pleurotus eryngii fermented quinoa powder with high antioxidant activity, comprising:

[0090] (1) A Pleurotus erythrorhizome strain (purchased from the Minyuan Edible Fungus Plant in Bayi Township, Wusheng County, with the strain number "Changbai Mountain No. 1") was inoculated into a potato dextrose agar medium at a volume of 10% by weight, and cultured in the dark at 28°C for 12 days to obtain a solid strain; wherein the components and contents of the potato dextrose agar medium are as follows: 12 g / L potato extract powder, 20 g / L glucose, and 14 g / L agar;

[0091] (2) inoculating the solid strain into a liquid culture medium at an inoculum size of 10% by weight, and stirring and culturing the culture at 28°C and 150 rpm for 12 days to obtain a Pleurotus eryngii seed solution; wherein the liquid culture medium is composed of the following components in terms of weight-volume ratio (g / mL): 30% potato juice, 4% glucose, 0.1% KH2PO4, 0.1% MgSO4·7H2O, and the remainder water;

[0092] (3) 55 g of black quinoa (purchased from Ganzhou Kangrui Agricultural Products Co., Ltd.) was soaked in pure water for 12 h to obtain soaked black quinoa, and then the soaked quinoa was sterilized at 120 ° C for 25 min to obtain quinoa culture medium (the dry weight of black quinoa in the quinoa culture medium was 55 g);

[0093] (4) 10 mL of Pleurotus eryngii seed liquid was inoculated into quinoa culture medium, and 10 mL of sterile water was added, and the mixture was placed in a constant temperature incubator at 28° C. for 22 days in the dark to obtain a fermentation product;

[0094] (5) The fermentation product was pre-freeze-dried at -40 ° C for 2 h, and then the main freeze-drying process was carried out according to the freeze-drying procedure to obtain the freeze-dried fermentation product; the freeze-dried fermentation product was crushed and passed through a 60-mesh sieve to obtain Pleurotus eryngii fermented quinoa powder (i.e., fermented quinoa); wherein the freeze-drying procedure is the first section, the second section, the third section, the fourth section, the fifth section, the sixth section, the seventh section, the eighth section and the ninth section executed in sequence, and the parameter control is as follows: the first section: temperature -50 ° C, normal pressure, time 5 h; the second section: temperature The first section is -40℃, vacuum degree 22Pa, time 3h; the third section is -30℃, vacuum degree 22Pa, time 5h; the fourth section is -15℃, vacuum degree 22Pa, time 4h; the fifth section is -10℃, vacuum degree 22Pa, time 2h; the sixth section is -5℃, vacuum degree 22Pa, time 2h; the seventh section is 5℃, vacuum degree 10Pa, time 8h; the eighth section is 15℃, vacuum degree 10Pa, time 4h; the ninth section is 30℃, vacuum degree 10Pa, time 8h.

[0095] Example 2

[0096] The preparation method of the Pleurotus eryngii fermented quinoa powder with high antioxidant activity provided in this embodiment is basically the same as that in Example 1, except that:

[0097] (5) The fermentation product was pre-freeze-dried at -30 ° C for 2 h, and then the main freeze-drying process was carried out according to the freeze-drying procedure to obtain the freeze-dried fermentation product; the freeze-dried fermentation product was crushed and passed through a 60-mesh sieve to obtain Pleurotus eryngii fermented quinoa powder (i.e., fermented quinoa); wherein the freeze-drying procedure is the first section, the second section, the third section, the fourth section, the fifth section, the sixth section, the seventh section, the eighth section and the ninth section executed in sequence, and the parameter control is as follows: the first section: temperature -50 ° C, normal pressure, time 4 h; the second section: temperature The first section is -40℃, vacuum degree 22Pa, time 3h; the third section is -30℃, vacuum degree 22Pa, time 4h; the fourth section is -20℃, vacuum degree 22Pa, time 2h; the fifth section is -10℃, vacuum degree 22Pa, time 2h; the sixth section is -2℃, vacuum degree 22Pa, time 2h; the seventh section is 6℃, vacuum degree 10Pa, time 6h; the eighth section is 20℃, vacuum degree 10Pa, time 4h; the ninth section is 25℃, vacuum degree 10Pa, time 6h.

[0098] Comparative Example 1 (without using Pleurotus erythrorhizome)

[0099] This comparative example provides a method for preparing quinoa powder, comprising:

[0100] 55 g of black quinoa (purchased from Ganzhou Kangrui Agricultural Products Co., Ltd.) was soaked in water for 12 h to obtain soaked quinoa, and then the soaked quinoa was sterilized at 120° C. for 25 min to obtain a quinoa culture medium (the dry weight of black quinoa in the quinoa culture medium was 55 g);

[0101] 10 mL of sterile water was added to the quinoa culture medium, and the culture was carried out in a constant temperature incubator at 28° C. in the dark for 22 days to obtain the product;

[0102] The product was first pre-freeze-dried at -40°C for 2 hours, and then subjected to main freeze-drying according to the freeze-drying procedure. After being crushed, it was passed through a 60-mesh sieve to obtain quinoa powder (i.e., unfermented quinoa). The freeze-drying procedure consisted of the first, second, third, fourth, fifth, sixth, seventh, eighth and ninth sections, which were executed in sequence. The parameters were controlled as follows: Section 1: temperature -50°C, normal pressure, time 5 hours; Section 2: temperature -40°C, vacuum 22 Pa, time 3 hours ; The third section: temperature -30℃, vacuum 22Pa, time 5h; the fourth section: temperature -15℃, vacuum 22Pa, time 4h; the fifth section: temperature -10℃, vacuum 22Pa, time 2h; the sixth section: temperature -5℃, vacuum 22Pa, time 2h; the seventh section: temperature 5℃, vacuum 10Pa, time 8h; the eighth section: temperature 15℃, vacuum 10Pa, time 4h; the ninth section: temperature 30℃, vacuum 10Pa, time 8h.

[0103] Comparative Example 2 (hot air drying)

[0104] The preparation method of the fermented quinoa powder of Pleurotus eryngii provided in this comparative example is basically the same as that in Example 1, except that:

[0105] (5) The fermentation product was spread onto a culture dish, and then placed in a hot air drying oven at a temperature of 55°C for hot air drying for 5 hours to obtain a hot air dried fermentation product; the hot air dried fermentation product was crushed and passed through a 60-mesh sieve to obtain Pleurotus eryngii fermented quinoa powder.

[0106] Application Example 1

[0107] This application example provides a protein bar, which includes the following raw materials in parts by mass: 10 parts of a protein composition (the protein composition is composed of soy protein isolate and whey protein in a mass ratio of 1:1), 10 parts of Pleurotus ostreatus fermented quinoa powder (Pleurotus ostreatus fermented quinoa powder prepared by the method in Example 1), 10 parts of maltitol, 10 parts of polydextrose, 10 parts of wheat flour, 10 parts of berry powder, 15 parts of chocolate, 10 parts of whole milk powder, 4 parts of coconut oil, 3 parts of glycerin, 3 parts of red beet powder, 2 parts of chia seed powder, 2 parts of phospholipids, and 1 part of edible salt.

[0108] The method for preparing the protein bar provided in this application example comprises the following steps:

[0109] Mix 10 parts of the protein composition, 10 parts of fermented quinoa powder with Pleurotus eryngii, 10 parts of maltitol, 10 parts of polydextrose, 10 parts of wheat flour, 10 parts of berry powder, 15 parts of chocolate, 10 parts of whole milk powder, 4 parts of coconut oil, 3 parts of glycerin, 3 parts of red beet powder, 2 parts of chia seed powder, 2 parts of phospholipids and 1 part of edible salt to prepare a powder;

[0110] Heat 10 parts of polydextrose and 10 parts of maltitol at 160°C to form a syrup with a sugar content of 85.5 degrees. Add the powder to the syrup with a sugar content of 85.5 degrees, stir and mix evenly, and mix the ingredients.

[0111] The mixed material is pressed into shape using a roller press to control the thickness between 5 cm and 6 cm, and then cut into strip-shaped protein bars with a length of 12 to 13 cm and a width of 5 to 6 cm. The protein bars are cooled to room temperature to obtain protein bars.

[0112] Experiment 1

[0113] The following measurements were performed on the quinoa powder fermented with Pleurotus eryngii in Example 1-2, the quinoa powder in Comparative Example 1, and the quinoa powder fermented with Pleurotus eryngii in Comparative Example 2 as samples, respectively. The measurement results are shown in Table 1.

[0114] Protein: Determine the protein content in the sample according to GB5009.5-2016;

[0115] Total sugar: Determine total sugar according to the phenol-sulfuric acid method: add 25 mL of anhydrous ethanol (80% by mass) to 1 g of sample, let it stand for 30 min, centrifuge at 3220 × g for 15 min, discard the supernatant, add 20 mL of ultrapure water, and place in a constant temperature water bath at 80°C for 2 h. After cooling, take 1 mL of the supernatant, add 0.5 mL of phenol (6% by mass) and 2.5 mL of sulfuric acid, and measure the absorbance at 490 nm after 30 min to obtain the total sugar content;

[0116] Lysine: The lysine content in the sample was determined according to GB 5009.124-2016.

[0117] Table 1 Measurement results

[0118] project Protein (g / 100g) Total sugar (mg / g) Lysine (g / 100g) Example 1 12.65 7.21 0.83 Example 2 12.87 7.33 0.83 Comparative Example 1 11.37 5.45 0.69 Comparative Example 2 12.43 6.79 0.74

[0119] As shown in Table 1, the protein, total sugar, and lysine contents in the quinoa powder fermented with Pleurotus eryngii in Examples 1-2 are all higher than those in the comparative example. The above results illustrate that the method provided by the present invention can effectively increase the protein, total sugar, and lysine contents in quinoa, thereby obtaining quinoa powder fermented with Pleurotus eryngii having high protein, total sugar, and lysine contents.

[0120] Experiment 2

[0121] The following measurements were performed on the quinoa powder fermented with Pleurotus eryngii in Example 1-2, the quinoa powder in Comparative Example 1, and the quinoa powder fermented with Pleurotus eryngii in Comparative Example 2 as samples. The measurement results are shown in Table 2.

[0122] Total flavonoids: The total flavonoids content in the sample was determined according to SN / T 4592-2016 standard;

[0123] DPPH free radical scavenging rate: The DPPH free radical scavenging rate of the sample was determined according to the method of the purchased Solebaugh DPPH free radical scavenging ability test kit.

[0124] Table 2 Measurement results

[0125] project Total flavonoids (mg RE / g) DPPH free radical scavenging rate (%) Example 1 0.630 50.03 Example 2 0.610 48.71 Comparative Example 1 0.350 25.46 Comparative Example 2 0.504 41.03

[0126] As can be seen from Table 2, the total flavonoids content and DPPH radical scavenging rate of the quinoa powder fermented with Pleurotus eryngii in Examples 1-2 are higher than those of the comparative example, indicating that the method provided by the present invention can effectively improve the total flavonoids content and antioxidant activity of quinoa, and obtain quinoa powder fermented with Pleurotus eryngii with high total flavonoids content and high antioxidant activity, which enhances the scientific value of quinoa as a natural antioxidant and promotes the transformation of quinoa from a traditional food to a high-value-added functional raw material.

[0127] Experiment 3

[0128] 1. Water holding capacity test

[0129] The quinoa powder fermented with Pleurotus eryngii in Example 1 and the quinoa powder in Comparative Example 1 were used as samples for water holding capacity test: 0.5 g of sample was weighed into a centrifuge tube, 1 ml of distilled water was added, the sample was allowed to stand for 30 min, stirred, and fully shaken, and centrifuged at room temperature at 6000 r / min for 20 min. The upper layer of water in the centrifuge tube was discarded, the water on the tube wall was absorbed by filter paper, and the weight of the centrifuge tube and the precipitate was weighed; the water holding capacity was calculated according to formula (1):

[0130] Water holding capacity (g / g) = (m3-m2-m1) / m2 Formula (1)

[0131] Where m1 represents the weight of the centrifuge tube, g; m2 represents the mass of the weighed sample, g; m3 represents the weight of the centrifuge tube and precipitate, g.

[0132] 2. Oil retention test

[0133] The quinoa powder fermented with Pleurotus eryngii in Example 1 and the quinoa powder in Comparative Example 1 were used as samples for oil retention tests: a certain amount of sample was weighed into a centrifuge tube, 1 mL of soybean oil was added, stirred, and thoroughly shaken. The sample was centrifuged at room temperature at 6000 rpm for 20 minutes. The upper layer of oil in the centrifuge tube was discarded, the oil on the tube wall was absorbed with filter paper, and the weight of the centrifuge tube and the precipitate was weighed. The oil retention was calculated according to formula (2):

[0134] Oil retention (g / g) = (n3-n2-n1) / n2 Formula (2)

[0135] Wherein, n1 represents the weight of the centrifuge tube, g; n2 represents the mass of the weighed quinoa, g; n3 represents the weight of the centrifuge tube and the sediment, g.

[0136] 3. Emulsification test

[0137] The quinoa powder fermented with Pleurotus eryngii in Example 1 and the quinoa powder in Comparative Example 1 were used as samples for emulsification tests: the sample was dissolved in distilled water to prepare a quinoa solution with a concentration of 1 mg / mL, soybean oil was added at an oil-to-oil ratio of 3:2, and high-speed shearing was performed at 10,000 r / min for 2 minutes to obtain an emulsion; 100 μL of the emulsion was taken, 1 mL of 1% SDS solution (purchased from Sinopharm Chemical Reagent Co., Ltd.) was added to dilute it 50 times (i.e., the dilution factor was 50), and after thorough mixing, the absorbance value A0 was measured at 500 nm using an ultraviolet spectrophotometer; the emulsification was calculated according to formula (3):

[0138]

[0139] Where A0 represents the absorbance at 500 nm; D represents the dilution factor; C represents the protein concentration in g / mL; Indicates 0.01, optical path.

[0140] Figure 1 The water holding capacity test results and oil holding capacity test results of the quinoa powder fermented with Pleurotus eryngii in Example 1 of the present invention and the quinoa powder in Comparative Example 1; Figure 2 These are the emulsification test results of the quinoa powder fermented with Pleurotus ostreatus in Example 1 of the present invention and the quinoa powder in Comparative Example 1.

[0141] Depend on Figure 1 and Figure 2 It can be seen that the water holding capacity and oil holding capacity of the quinoa powder fermented by Pleurotus aviculare in Example 1 are lower than those of the quinoa powder in Comparative Example 1, and the emulsification property of the quinoa powder fermented by Pleurotus aviculare in Example 1 is higher than that of the quinoa powder in Comparative Example 1, which illustrates that the quinoa powder fermented by Pleurotus aviculare in Example 1 has the characteristics of low water holding capacity, low oil holding capacity and high emulsification property: low water holding capacity makes it easier for the quinoa powder fermented by Pleurotus aviculare to form a dry and crispy texture during processing (such as baking, frying or puffing), which is suitable for the development of snacks such as quinoa chips, cereal bars, and biscuits that need to maintain a crispy taste; low oil holding capacity reduces the amount of oil absorbed by the quinoa powder fermented by Pleurotus aviculare during frying or pan-frying, and is suitable as a healthy coating (such as tempura, fried chicken substitutes), reduces the fat content of the final product, and is in line with the trend of low-fat diet; high emulsification property indicates that the quinoa powder fermented by Pleurotus aviculare is easier to emulsify and has potential application value in the fields of cosmetics and the like.

[0142] Experiment 4

[0143] Artificial saliva, artificial gastric juice and artificial intestinal juice are all purchased from Xinxinfan Biotechnology Co., Ltd.

[0144] The quinoa powder fermented with Pleurotus eryngii in Example 1 and the quinoa powder in Comparative Example 1 were used as samples for in vitro digestibility tests:

[0145] The sample was dissolved in distilled water to prepare a protein solution with a mass fraction of 5%. 500 μL of protein solution was taken, and 500 μL of artificial saliva (insulated in a 37°C water bath) was added, mixed thoroughly, and placed in a 37°C water bath for 5 minutes to obtain a solution digested with artificial saliva; 500 μL of artificial gastric juice (insulated in a 37°C water bath) was added to the solution digested with artificial saliva, mixed thoroughly, and placed in a 37°C water bath for 2 hours to obtain a solution digested with artificial saliva and artificial gastric juice; 1000 μL of artificial intestinal juice (insulated in a 37°C water bath) was added to the solution digested with artificial saliva and artificial gastric juice, mixed thoroughly, and placed in a 37°C water bath for 1 hour to obtain a solution digested with artificial saliva. , artificial gastric juice and artificial intestinal juice digested solution; the solution digested with artificial saliva, artificial gastric juice and artificial intestinal juice was inactivated in a 90°C water bath for 5 minutes, centrifuged at 14,000×g for 10 minutes, the supernatant was collected, and the supernatant was ultrafiltered through an ultrafiltration tube at 8,000×g for 5 minutes; the protein content in the sample (i.e., undigested protein content), the protein content in the solution digested with artificial saliva and artificial gastric juice (i.e., gastric digested protein content), and the protein content in the solution digested with artificial saliva, artificial gastric juice and artificial intestinal juice (i.e., intestinal digested protein content) were measured respectively, and the digestibility was calculated based on the protein content before and after digestion. The calculation results are shown in Table 3;

[0146] Simulated gastric digestion digestibility (%) = (undigested protein content - gastric digested protein content) / undigested protein content × 100%;

[0147] Simulated intestinal digestive tract digestibility (%) = (undigested protein content - intestinal digested protein content) / undigested protein content × 100%.

[0148] Table 3 Measurement results

[0149] project Digestibility in simulated gastric tract (%) Simulated intestinal digestive tract digestibility (%) Example 1 40 74.67 Comparative Example 1 26.67 61.33

[0150] High in vitro digestibility is beneficial for improving the utilization of nutrients in quinoa. As shown in Table 3, the simulated gastric digestive tract digestibility and simulated intestinal digestive tract digestibility of the quinoa powder fermented with Pleurotus eryngii in Example 1 are both higher than those of the quinoa powder in Comparative Example 1, indicating that the in vitro digestibility of the fermented quinoa (i.e., the quinoa powder fermented with Pleurotus eryngii in Example 1) is higher than that of the quinoa powder in Comparative Example 1.

[0151] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing quinoa powder fermented with Pleurotus eryngii having high antioxidant activity, characterized in that: include: The Pleurotus erythrorhizome is inoculated into a solid culture medium at an inoculum rate of 8% to 10% by volume, and cultured in the dark to obtain a solid strain. Inoculating the solid strain into a liquid culture medium at an inoculum rate of 8% to 10% V / W, and performing stirring culture to obtain a Pleurotus eryngii seed liquid; sterilizing the soaked quinoa to obtain a quinoa culture medium; inoculating the Pleurotus eryngii seed liquid into the quinoa culture medium, adding sterile water, and fermenting in the dark to obtain a fermentation product; The fermentation product is freeze-dried, crushed and sieved to obtain Pleurotus eryngii fermented quinoa powder.

2. The method for preparing the Pleurotus eryngii fermented quinoa powder with high antioxidant activity according to claim 1, wherein The freeze-drying process includes a pre-freeze-drying process and a main freeze-drying process in sequence; During the pre-freeze-drying process, the temperature is -45 to -30°C and the time is 1 to 3 hours. The main freeze-drying process is carried out according to a freeze-drying program, which includes a first section, a second section, a third section, a fourth section, a fifth section, a sixth section, a seventh section, an eighth section and a ninth section that are executed in sequence. From the first section to the ninth section, the temperature is controlled and gradually increases.

3. The method for preparing the Pleurotus eryngii fermented quinoa powder with high antioxidant activity according to claim 2, wherein The parameters of the freeze-drying process are specifically controlled as follows: The first section: temperature -52 to -48°C, normal pressure, time 4 to 6 hours; The second section: temperature -42 ~ -38 ° C, vacuum degree 22 Pa, time 2 ~ 4 hours; The third section: temperature -32 ~ -28 ° C, vacuum degree 22 Pa, time 4 ~ 6 hours; The fourth section: temperature -20 to -15°C, vacuum degree 22 Pa, time 2 to 5 hours; The fifth section: temperature -12 to -8°C, vacuum degree 22 Pa, time 1 to 3 hours; The sixth section: temperature -6 to -2°C, vacuum degree 22 Pa, time 1 to 3 hours; Section 7: temperature 2-6°C, vacuum 10 Pa, time 6-10 hours; Section 8: temperature 10-20°C, vacuum 10 Pa, time 3-5 hours; Ninth section: temperature 25-35°C, vacuum degree 10 Pa, time 6-10 hours.

4. The method for preparing the Pleurotus eryngii fermented quinoa powder with high antioxidant activity according to claim 1, wherein The method of sterilizing the soaked quinoa to obtain the quinoa culture medium specifically comprises: soaking 50-60 g of quinoa in water for 10-14 hours to obtain the soaked quinoa, and then sterilizing the soaked quinoa at 110-130° C. for 20-30 minutes to obtain the quinoa culture medium.

5. The method for preparing the Pleurotus eryngii fermented quinoa powder with high antioxidant activity according to claim 4, characterized in that: The volume-to-mass ratio of the Pleurotus quinoa seed solution to the quinoa culture medium is (8-10 mL): (50-60 g dry weight); And / or, the volume mass ratio of the sterile water to the quinoa culture medium is (8-10 mL): (50-60 g dry weight).

6. The method for preparing the Pleurotus eryngii fermented quinoa powder with high antioxidant activity according to claim 1, characterized in that: The temperature of the dark-proof culture is 25-28° C., and the time is 10-12 days; And / or, the agitation culture temperature is 25-28°C, the rotation speed is 120-150 rpm, and the time is 10-12 days; And / or, the temperature of the light-proof fermentation is 25-28° C., and the time is 20-22 days.

7. The method for preparing the Pleurotus eryngii fermented quinoa powder with high antioxidant activity according to claim 1, characterized in that: The quinoa is any one of black quinoa, white quinoa and red quinoa; And / or, the solid culture medium is potato dextrose agar medium, and the components and contents of the potato dextrose agar medium are as follows: potato extract powder 12 g / L, glucose 20 g / L, agar 14 g / L; And / or, the liquid culture medium is composed of the following components in terms of weight to volume ratio g / mL: 30% potato juice, 4% glucose, 0.1% KH2PO4, 0.1% MgSO4·7H2O, and the remainder water.

8. A kind of Pleurotus eryngii fermented quinoa powder, characterized in that: The Pleurotus aviculare fermented quinoa powder is prepared by the preparation method of the Pleurotus aviculare fermented quinoa powder with high antioxidant activity according to any one of claims 1 to 7.

9. Use of the Pleurotus aviculare fermented quinoa powder obtained by the method for preparing the Pleurotus aviculare fermented quinoa powder with high antioxidant activity according to any one of claims 1 to 7 or the Pleurotus aviculare fermented quinoa powder according to claim 8 in preparing protein food.

10. Use of the method for preparing quinoa powder fermented with Pleurotus eryngii having high antioxidant activity according to any one of claims 1 to 7 in quinoa cultivation, characterized in that: Quinoa is cultured using the method.

Images