Selenium-enriched malt flour as well as preparation method and application thereof

Abstract

The invention provides selenium-enriched malt flour as well as a preparation method and application thereof, and belongs to the technical field of food processing. The method comprises the following steps: spraying a selenium-rich nutrient solution in the flowering stage of wheat to obtain selenium-rich wheat grains; mixing the selenium-enriched wheat grains with a selenomethionine solution for accelerating germination to obtain selenium-enriched malt; and mixing the selenium-enriched malt with the nano-selenium solution, adding the mixed strain, fermenting, pulping, and performing vacuum freeze drying to obtain the selenium-enriched malt flour. According to the method disclosed by the invention, different forms of selenium elements are respectively supplemented in the three stages of seed setting, germination and fermentation of the wheat, and the selenium elements can be fully enriched and converted in different culture forms, so that the content of organic selenium in the selenium-enriched malt flour is greatly increased. The selenium-enriched malt flour prepared by the preparation method has obvious effects of resisting tumors and eliminating nodules, has an auxiliary protection effect on chemical liver injury, has very high nutrition and health-care values, and can be used for preparing functional foods.

Description

Technical Field

[0001] The invention belongs to the technical field of food processing, and in particular relates to selenium-enriched malt powder and a preparation method and application thereof. Background Art

[0002] Selenium malt is a selenium supplement product rich in natural organic selenium, which uses wheat as an active carrier for selenium conversion. Through the absorption and conversion effect of the germination process, selenium is enriched in the amino acids, proteins and other molecules contained in the malt. Compared with inorganic selenium, organic selenium is more easily absorbed by human tissues and participates in human life metabolism activities. Daily quantitative selenium supplementation is beneficial to preventing selenium deficiency, sub-health, cancer, excessive heavy metals and toxins in the body, etc.

[0003] The existing preparation method of selenium malt has a low content of organic selenium, which is not conducive to the full absorption and utilization of the human body, and greatly reduces the nutritional and health value of malt powder. Summary of the invention

[0004] In view of this, the object of the present invention is to provide a selenium-enriched malt powder and a preparation method and application thereof, so as to solve the problem of low organic selenium content in the existing selenium malt.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for preparing selenium-enriched malt powder, comprising the following steps:

[0007] 1) Spraying a selenium-enriched nutrient solution on wheat during its flowering period to obtain selenium-enriched wheat grains;

[0008] 2) mixing the selenium-enriched wheat grains and the selenomethionine solution, and accelerating germination to obtain selenium-enriched malt;

[0009] 3) mixing the selenium-enriched malt and the nano-selenium solution, adding the mixed bacteria to ferment and then beating the mixture, and vacuum freeze-drying to obtain the selenium-enriched malt powder.

[0010] Preferably, the selenium-rich nutrient solution comprises the following components in mass concentrations: 200-250 ppm sodium selenite, 9-18 ppm sodium nitrophenolate, 1-5 ppm glycine and the remainder water; the spraying amount of the selenium-rich nutrient solution is 100-150 mL / mu.

[0011] Preferably, the concentration of the selenomethionine solution is 5 to 8 μM, and the mass volume ratio of the mixture of the selenium-enriched wheat grains and the selenomethionine solution is 1 g: 5 to 7 mL.

[0012] Preferably, the germination temperature is 25-30° C., and the germination time is 24-72 hours.

[0013] Preferably, the selenium content in the nano-selenium solution is 0.025-0.075 mol / L; and the mass volume ratio of the mixture of the selenium-enriched malt and the nano-selenium solution is 1 g: 5-7 mL.

[0014] Preferably, the mixed bacteria are Candida utilis and Lactobacillus plantarum, and the mass ratio of Candida utilis to Lactobacillus plantarum is 2-4:1; the inoculation amount of the mixed bacteria is 3-7% of the total mass of selenium-enriched malt and nano-selenium solution.

[0015] Preferably, the fermentation temperature is 28-32° C., and the fermentation time is 28-32 h.

[0016] Preferably, the temperature of the vacuum freeze-drying is -28 to -38°C, the vacuum degree of the vacuum freeze-drying is 5 to 15 Pa, and the time of the vacuum freeze-drying is 1 to 2 hours.

[0017] The invention also provides selenium-enriched malt powder prepared by the preparation method.

[0018] The present invention also provides the selenium-enriched malt powder prepared by the preparation method or the use of the selenium-enriched malt powder in preparing functional food with auxiliary protective effect on chemical liver damage.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The invention sprays the selenium-rich nutrient solution during the flowering period of wheat to increase the permeability of the leaf surface, promote the absorption and enrichment of inorganic selenium by wheat, stimulate the activity of enzymes in the wheat body, improve the photosynthesis efficiency, and accelerate the conversion process of inorganic selenium in the wheat body to organic selenium.

[0021] The present invention adds a selenomethionine solution during the germination process. As an organic selenium source, selenomethionine can significantly improve the germination index, germination rate and peroxidase (POD) activity of wheat seeds, thereby promoting seed germination; at the same time, selenomethionine can increase the absorption efficiency of wheat seeds for selenium, thereby increasing the organic selenium content in wheat grains.

[0022] The present invention utilizes a mixed strain consisting of Candida utilis and Lactobacillus plantarum to ferment a selenium-enriched malt formulation, and adds a nano-selenium solution during the fermentation process. Nano-selenium, as a nutrient source for the strain, can promote the growth of microorganisms during the fermentation process and improve the fermentation performance of the strain; meanwhile, it can accelerate the conversion rate of organic selenium during the fermentation process.

[0023] The invention supplements selenium in different forms in the three stages of wheat seed setting, germination and fermentation, and can fully enrich and transform selenium under different culture forms, thereby greatly increasing the content of organic selenium in selenium-enriched malt powder. The selenium-enriched malt powder prepared by the invention has obvious anti-tumor and nodule-eliminating effects, can have an auxiliary protective effect on chemical liver damage, has high nutritional and health value, and can be used in the preparation of functional foods. DETAILED DESCRIPTION

[0024] The present invention provides a method for preparing selenium-enriched malt powder, comprising the following steps:

[0025] 1) Spraying a selenium-enriched nutrient solution on wheat during its flowering period to obtain selenium-enriched wheat grains;

[0026] 2) mixing the selenium-enriched wheat grains and the selenomethionine solution, and accelerating germination to obtain selenium-enriched malt;

[0027] 3) mixing the selenium-enriched malt and the nano-selenium solution, adding the mixed bacteria to ferment and then beating the mixture, and vacuum freeze-drying to obtain the selenium-enriched malt powder.

[0028] In the present invention, a selenium-rich nutrient solution is sprayed during the flowering period of wheat to obtain selenium-rich wheat grains. The selenium-rich nutrient solution includes the following components in mass concentrations: 200-250ppm sodium selenite, 9-18ppm sodium nitrophenolate, 1-5ppm glycine and the remainder of water; the concentration of the sodium selenite is preferably 220-240ppm; the concentration of the sodium nitrophenolate is preferably 10-16ppm, and sodium nitrophenolate can increase the permeability of the cuticle of the leaf surface, improve the penetration rate of nutrient elements and the utilization rate of the selenium-rich nutrient solution on the leaf surface; sodium nitrophenolate can also increase the respiration of the leaves, expand the stomata, so that the selenium-rich nutrient solution enters the stomata more and faster, and improves the absorption efficiency; sodium nitrophenolate can also promote the expansion, enlargement and thickening of wheat leaves. , increase the contact area of ​​the leaf surface with the nutrient elements. The larger the contact area, the higher the absorption rate of the leaf to the nutrient elements. The concentration of the glycine is preferably 2-4ppm. Glycine can increase the absorption of phosphorus and potassium elements by wheat, improve the stress resistance of wheat, promote the photosynthesis of wheat, increase the chlorophyll content of wheat, stimulate the activity of various enzymes in wheat, promote the penetration of carbon dioxide, make photosynthesis more vigorous, enhance the metabolism of wheat, and greatly accelerate the conversion process of inorganic selenium to organic selenium in wheat. The spraying amount of the selenium-rich nutrient solution is preferably 100-150mL / mu, and more preferably 110-140mL / mu.

[0029] In the present invention, selenium-enriched wheat grains and selenomethionine solution are mixed and germinated to obtain selenium-enriched malt. The concentration of the selenomethionine solution is preferably 5-8 μM, more preferably 6-7 μM; the mass volume ratio of the selenium-enriched wheat grains and the selenomethionine solution is preferably 1 g: 5-7 mL, more preferably 1 g: 6 mL; the germination temperature is preferably 25-30°C, more preferably 26-29°C; the germination time is preferably 24-72 hours, more preferably 30-66 hours.

[0030] In the present invention, selenium-enriched malt and nano-selenium solution are mixed, mixed bacteria are added for fermentation, and then pulped, and vacuum freeze-dried to obtain selenium-enriched malt powder. The selenium content in the nano-selenium solution is preferably 0.025-0.075 mol / L, and more preferably 0.05 mol / L; the mass volume ratio of the mixture of selenium-enriched malt and nano-selenium solution is preferably 1g:5-7mL, and more preferably 1g:6mL; the mixed bacteria are Candida utilis and Lactobacillus plantarum, and the mass ratio of Candida utilis and Lactobacillus plantarum is preferably 2-4:1, and more preferably 3:1; the inoculation amount of the mixed bacteria is preferably 3-7% of the total mass of selenium-enriched malt and nano-selenium solution, and more preferably 1g:6mL; the ... It is preferably 4-6% of the total mass of selenium-enriched malt and nano-selenium solution; the fermentation temperature is preferably 28-32°C, and more preferably 29-31°C; the fermentation time is preferably 28-32h, and more preferably 29-31h; the vacuum freeze-drying temperature is preferably -28--38°C, and more preferably -30--37°C; the vacuum degree of the vacuum freeze-drying is preferably 5-15Pa, and more preferably 7-14Pa; the vacuum freeze-drying time is preferably 1-2h, and more preferably 1.5h.

[0031] The invention also provides selenium-enriched malt powder prepared by the preparation method.

[0032] The present invention also provides the selenium-enriched malt powder prepared by the preparation method or the use of the selenium-enriched malt powder in preparing functional food with auxiliary protective effect on chemical liver damage.

[0033] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0034] Materials used in the present invention: Candida utilis, item number hz11660; Lactobacillus bulgaricus, item number hz11705; purchased from Shanghai Huzhen Biotechnology Co., Ltd.; Lactobacillus plantarum, ATCC8014, purchased from Qiyi Biotechnology (Shanghai) Co., Ltd.;

[0035] Liver function test kits: alanine aminotransferase (ALT), alkaline phosphatase (ALP), albumin (ALB), and total bilirubin (TBIL) were purchased from Beijing Antu Bioengineering Co., Ltd., and rat liver cancer specific indicator detection kits (GST, γ-GT) were purchased from Shanghai Bolson Biotechnology Co., Ltd.

[0036] The preparation method of nano-selenium is carried out according to the literature (Chen JR, Feng T, Wang B, et al. Enhancing organic selenium content and antioxidant activities of soy sauce using nano-selenium during soybean soaking [J]. Frontiers in Nutrition, 2022, 9: 970-206.): 50 mL of 0.1 mol / L, 0.2 mol / L, and 0.3 mol / L Na2SeO3 and 60 mL of 10 g / L chitosan solution were respectively placed in a 500 mL stoppered brown conical flask, shaken in a shaker (28 ° C) for 30 min, 50 mL of 0.5 mol / L ascorbic acid solution was added, and distilled water was added to a total volume of 200 mL. Mix well, place in a shaker (28 ° C) and shake for 90 min to obtain 0.025 mol / L, 0.05 mol / L, and 0.075 mol / L (in terms of Se) red nano-selenium solutions.

[0037] Example 1

[0038] During the flowering period of wheat, a selenium-rich nutrient solution (230 ppm sodium selenite, 14 ppm sodium nitrophenolate, 3 ppm glycine and the remainder water) is sprayed at a spraying rate of 130 mL / mu to obtain selenium-rich wheat grains; the selenium-rich wheat grains and a 7 μM selenomethionine solution are mixed at a mass volume ratio of 1 g: 6 mL, and the mixture is germinated at 28°C for 48 h to obtain selenium-rich malt; the selenium-rich malt and a nano-selenium solution with a selenium content of 0.05 mol / L are mixed at a mass volume ratio of 1 g: 6 mL, and mixed bacteria are added (the mass ratio of Candida utilis and Lactobacillus plantarum is 3: 1), and the mixture is fermented at 30°C for 30 h, followed by pulping and vacuum freeze-drying (-32°C, 10 Pa, 1.5 h) to obtain selenium-rich malt powder.

[0039] Example 2

[0040] During the flowering period of wheat, a selenium-rich nutrient solution (200 ppm sodium selenite, 9 ppm sodium nitrophenolate, 1 ppm glycine and the remainder water) is sprayed at a spraying rate of 100 mL / mu to obtain selenium-rich wheat grains; the selenium-rich wheat grains and a 5 μM selenomethionine solution are mixed at a mass volume ratio of 1 g:5 mL, and the mixture is germinated at 25°C for 24 hours to obtain selenium-rich malt; the selenium-rich malt and a nano-selenium solution with a selenium content of 0.025 mol / L are mixed at a mass volume ratio of 1 g:5 mL, and mixed bacteria are added (the mass ratio of Candida utilis and Lactobacillus plantarum is 2:1), and the mixture is fermented at 28°C for 28 hours, then pulped, and vacuum freeze-dried (-28°C, 5 Pa, 1 hour) to obtain selenium-rich malt powder.

[0041] Example 3

[0042] During the flowering period of wheat, a selenium-rich nutrient solution (250 ppm sodium selenite, 18 ppm sodium nitrophenolate, 5 ppm glycine and the remainder water) is sprayed at a spraying rate of 150 mL / mu to obtain selenium-rich wheat grains; the selenium-rich wheat grains and a selenomethionine solution with a concentration of 8 μM are mixed at a mass volume ratio of 1 g:7 mL, and germinated at a temperature of 30°C for 72 hours to obtain selenium-rich malt; the selenium-rich malt and a nano-selenium solution with a selenium content of 0.075 mol / L are mixed at a mass volume ratio of 1 g:7 mL, and mixed strains (the mass ratio of Candida utilis and Lactobacillus plantarum is 4:1) are added, and fermented at a temperature of 32°C for 32 hours, followed by pulping and vacuum freeze-drying (-38°C, 15 Pa, 2 hours) to obtain selenium-rich malt powder.

[0043] Comparative Example 1

[0044] The difference from Example 1 is that "Lactobacillus plantarum" is replaced by "Lactobacillus bulgaricus".

[0045] Comparative Example 2

[0046] The difference from Example 1 is that glycine in the selenium-enriched nutrient solution is removed.

[0047] Comparative Example 3

[0048] The difference from Example 1 is that the nano-selenium solution is removed and the selenium-enriched malt is directly pulped and fermented.

[0049] Experimental Example 1

[0050] Determination of germination rate of selenium-enriched malt

[0051] The selenium-enriched wheat grains obtained by culturing according to the method in Example 1 were selected, and three groups of experiments, A, B, C, D, and E, were set up, with 100 grains in each group. Group A adopted the method in Example 1 for germination treatment, in Group B, the 7 μM selenomethionine solution in Example 1 was replaced with clean water, in Group C, the 7 μM selenomethionine solution in Example 1 was replaced with 230 ppm of sodium selenite, in Group D, the 7 μM selenomethionine solution in Example 1 was replaced with a 3 μM selenomethionine solution, and in Group E, the 7 μM selenomethionine solution in Example 1 was replaced with a 10 μM selenomethionine solution. The germination conditions of the selenium-enriched wheat grains in different treatment groups were recorded.

[0052] Experimental results: as shown in Table 1.

[0053] Table 1 Germination of selenium-enriched wheat grains in different treatment groups

[0054] Group Number of germination / grain Germination rate A 98 98％ B 69 69％ C 81 81％ D 74 74％ E 52 52％

[0055] As shown in Table 1, the use of selenomethionine solution can significantly improve the germination rate of selenium-enriched wheat grains and promote the germination of selenium-enriched wheat grains compared with water and sodium selenite. The concentration of selenomethionine solution significantly affects the germination of selenium-enriched wheat grains. If the concentration of selenomethionine solution is too low, the promoting effect on the germination of selenium-enriched wheat grains is low, while if the concentration is too high, the activity of enzymes in selenium-enriched wheat grains will be inhibited, which is not conducive to the germination of selenium-enriched wheat grains.

[0056] Experimental Example 2

[0057] Selenium content test

[0058] The selenium content in the selenium-rich malt powder prepared in Examples 1 to 3 and Comparative Examples 1 to 3 was tested. The detection method referred to the detection method for the total selenium content of the product in GB5009.932017 "Determination of Selenium in Foods". However, since this method detects all the selenium content in the selenium-rich malt powder, it is impossible to distinguish between organic selenium and inorganic selenium. Therefore, after measuring the total selenium content in the selenium-rich malt powder, the same selenium-rich malt powder is extracted with ethanol, and the organic selenium in the malt powder is extracted into ethanol. The content is determined again by the method in GB5009.932017 "Determination of Selenium in Foods", and the proportion of organic selenium in the same malt powder can be obtained.

[0059] Experimental results: as shown in Table 2.

[0060] Table 2 Selenium content in different treatment groups

[0061] Group Total selenium content mg / kg Organic selenium content mg / kg Organic selenium content% Example 1 522 503 96.36 Example 2 508 484 95.28 Example 3 513 491 95.71 Comparative Example 1 446 377 84.53 Comparative Example 2 427 354 82.90 Comparative Example 3 395 307 77.72

[0062] Experimental Example 3

[0063] SD clean rats, male, weighing 180-220 g, were purchased from Shanghai Slake Experimental Animal Co., Ltd., with the experimental animal production license number: SCXK (Shanghai) 2003-0003. The rats were housed in separate cages and, after 3 days of adaptive feeding, were randomly divided into 5 groups, with 10 rats in each group. Group I: negative control group, no cancer induction and no addition of selenium-enriched malt powder; Group II: model group, sodium selenite was added to the diets of Group I and Group II until the selenium content reached 0.1 mg / kg; Group III to Group V, the selenium-enriched malt powder prepared in Example 1 was added to the diets until the selenium content reached 0.3, 1.0, and 3.0 mg / kg. The rats in each group were fed with restricted feed, with a maximum daily feed intake of 25 g per rat. Except for the negative control group, the other four groups were modeled according to the method in the literature (Zou Jing, Chen Jianjie. Preventive effect of Bushen prescription on diethylnitrosamine-induced rat liver cancer [J]. Journal of Integrated Traditional Chinese and Western Medicine for Hepatology 2003, 13(5): 278-280): drinking 100 mg / L DEN solution freshly prepared with sterile tap water to maintain a DEN intake of about 10 mg / kg per day for 16 consecutive weeks, and then drinking sterile tap water until the end of the experiment at the end of the 18th week. At the end of the 18th week, blood was collected from the orbits of the rats in each group, and the plasma was separated with heparin anticoagulation and frozen at -20℃ for biochemical index analysis.

[0064] Number of liver surface cancer nodules: Counted according to the literature (Mereno FS, Rizzi M BSL, Dagli MLZ, et al. Inhibitory effect of B-corotence on preneoplastic lesions induced in wister rats by theresitent hepatocyte model [J]. Carcinogenesis. 1991, 12: 1817-1822). Plasma alanine aminotransferase (ALT), alkaline phosphatase (ALP), albumin (ALB), and total bilirubin (TBIL) were measured using an automatic biochemical analyzer; GST and γ-GT were measured using a colorimetric method according to the instructions of the kit.

[0065] Experimental results: as shown in Table 3.

[0066] Table 3 Analysis results of liver surface cancer nodules and biochemical indicators in different treatment groups

[0067]

[0068] As shown in Table 3, compared with group II, the number of liver surface cancer nodules, ALT, ALP, ALB, TBIL, GST and γ-GT in groups III to V were significantly reduced, indicating that the selenium-enriched malt powder prepared by the present invention has the effects of alleviating liver damage, delaying the formation of liver cancer in rats, and inhibiting the formation of liver cancer nodules.

[0069] It can be seen from the above embodiments and experimental examples that the selenium-enriched malt powder prepared by the present invention has a good content of organic selenium, can promote human absorption, and has the effects of alleviating liver damage, delaying the formation of liver cancer, and inhibiting the formation of liver cancer nodules.

[0070] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing selenium-enriched malt powder, characterized in that: The following steps are involved: 1) Spraying a selenium-enriched nutrient solution on wheat during its flowering period to obtain selenium-enriched wheat grains; 2) mixing the selenium-enriched wheat grains and the selenomethionine solution, and accelerating germination to obtain selenium-enriched malt; 3) mixing the selenium-enriched malt and the nano-selenium solution, adding the mixed bacteria to ferment and then beating the mixture, and vacuum freeze-drying to obtain the selenium-enriched malt powder.

2. The preparation method according to claim 1, characterized in that: The selenium-rich nutrient solution comprises the following components in mass concentrations: 200-250 ppm sodium selenite, 9-18 ppm sodium nitrophenolate, 1-5 ppm glycine and the remainder water; the spraying amount of the selenium-rich nutrient solution is 100-150 mL / mu.

3. The preparation method according to claim 1, characterized in that: The concentration of the selenomethionine solution is 5-8 μM, and the mass volume ratio of the selenium-enriched wheat grains and the selenomethionine solution is 1 g: 5-7 mL.

4. The preparation method according to claim 1, characterized in that: The germination temperature is 25-30° C., and the germination time is 24-72 hours.

5. The preparation method according to claim 1, characterized in that: The selenium content in the nano-selenium solution is 0.025-0.075 mol / L; the mass volume ratio of the mixture of the selenium-enriched malt and the nano-selenium solution is 1 g: 5-7 mL.

6. The preparation method according to claim 1, characterized in that: The mixed bacteria are Candida utilis and Lactobacillus plantarum, the mass ratio of Candida utilis and Lactobacillus plantarum is 2-4:1; the inoculation amount of the mixed bacteria is 3-7% of the total mass of selenium-enriched malt and nano-selenium solution.

7. The preparation method according to claim 1, characterized in that: The fermentation temperature is 28-32° C., and the fermentation time is 28-32 hours.

8. The preparation method according to claim 1, characterized in that: The temperature of the vacuum freeze drying is -28 to -38°C, the vacuum degree of the vacuum freeze drying is 5 to 15 Pa, and the time of the vacuum freeze drying is 1 to 2 hours.

9. Selenium-enriched malt powder prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the selenium-enriched malt powder prepared by the preparation method according to any one of claims 1 to 8 or the selenium-enriched malt powder according to claim 9 in the preparation of functional foods having auxiliary protective effects on chemical liver damage.

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