Fresh corn fermentation method and application thereof in product processing

Abstract

The invention provides a fermentation method of fresh corn and application thereof in product processing, and the operation steps are as follows: S1: harvesting and treating fresh corn cobs to obtain harvested fresh corn cobs, S2: treating the harvested fresh corn cobs to obtain crushed fresh corn, S3: preparing a fresh corn culture medium from the crushed fresh corn, S4: culturing ganoderma lucidum strains to obtain ganoderma lucidum fermentation seeds, and S5: fermenting the ganoderma lucidum fermentation seeds to obtain the product. S5, inoculating ganoderma lucidum fermentation seeds into the fresh corn culture medium, and fermenting to obtain fermented fresh corn, and S6, drying and crushing the fermented fresh corn to obtain the fermented fresh corn flour which is applied to product processing. The fermented fresh corn flour obtained through fermentation is rich in nutrition and high in active substance content, has the biological activities of improving the immunity of the organism, adjusting blood sugar and blood fat, resisting oxidation and the like, is applied to product processing, enriches the types of processed products, meets the requirements of consumers, and has good market prospects. An effective way is provided for prolonging a fresh corn industry chain and a lucid ganoderma processing industry chain, and the application prospect is wide.

Description

Technical Field

[0001] The invention belongs to the field of microbial fermentation in the field of biotechnology, and specifically relates to a fermentation method of fresh corn and application thereof in product processing. Background Art

[0002] Fresh corn refers to young corn with special flavor and quality, also known as fruit corn. It can be used as vegetables, fruits, food, feed, etc. Compared with ordinary corn, it is sweet, sticky, tender and fragrant. In terms of quality, it can be divided into sweet corn, super sweet corn, sweet sticky corn, sticky corn, etc., and in terms of kernel color, it can be divided into black, purple, yellow, white, variegated, etc. Fresh corn is rich in nutrients, with high content of trace elements such as calcium, magnesium, selenium, vitamins and amino acids; among them, black and purple fresh corn are rich in anthocyanins. Compared with ordinary corn, sticky corn has thin skin and no residue, high sugar content, high content of water-soluble protein and salt-soluble protein, and rich in vitamin E, vitamin B1, vitamin B2, vitamin C, inositol, choline and mineral elements.

[0003] Fresh corn has certain effects in preventing cancer, preventing blood vessel aging, and reducing cholesterol in the blood. It conforms to the healthy dietary concepts of today's mass consumers, such as "anti-oxidation, fine coarse grains, and balanced nutrition", and has become a high-end food favored by modern urbanites. The planting area of ​​fresh corn in my country has risen rapidly in recent years, and the consumption of fresh corn has also increased year by year. However, since the edible part of fresh corn is young and tender fruit that is not fully mature, the respiration and metabolism after picking are vigorous, the sugar conversion is fast, and it is easy to lose water and deteriorate, so fresh corn must be quickly frozen or vacuum packed immediately after picking, otherwise it will be difficult to store for a long time or supply the market throughout the year. At present, the market consumption of fresh corn is mainly fresh ear sales and quick freezing processing, and fresh corn processing is still in the primary processing stage. Because it is easily affected by factors such as production area, season, climate, and growth period, the market sales price of fresh corn fluctuates greatly, with the main fluctuation range being 2 to 6 yuan per kilogram. The large fluctuation in price poses a great challenge to the stable and healthy development of the fresh corn industry. At the same time, the only deep-processed fresh corn products on the market are corn juice, canned corn, etc. The product types are single and the varieties are few, which cannot meet the needs of consumers.

[0004] Yeast belongs to the fungi of higher microorganisms and is a single-cell microorganism. It can survive both under aerobic and anaerobic conditions. It is a natural fermentation agent that can be used for brewing production and can also be used as a model organism for scientific research. Saccharomyces cerevisiae is a large class of yeasts commonly used in production and life, such as fermentation of fruit wine, beer and flour products; in addition, yeast can also be eaten by humans, such as dry yeast powder or tea yeast. Some types of yeast have special metabolic pathways. For example, some terrestrial Issatchen yeast strains have the ability to decompose citric acid and can decompose citric acid for cell growth and metabolism. In the process of citric acid decomposition, rich metabolic intermediates are produced, which then flow to the synthesis pathway of sterols and fatty acids, etc., providing important intermediate metabolites for the synthesis and metabolism of certain active substances such as triterpenes.

[0005] Ganoderma lucidum is a precious edible and medicinal fungus, and is included in the list of "substances that are traditionally both food and Chinese medicinal materials". Ganoderma lucidum contains a variety of nutrients and active substances, such as protein, amino acids, polysaccharides, polypeptides, triterpenes, taurine, adenosine, alkaloids, volatile oils, mannitol, etc., among which the two most important active substances are triterpenes and polysaccharides. In traditional Chinese medicine in my country, Ganoderma lucidum has always been a highly recognized precious Chinese medicine, with physiological effects such as immunomodulation, anti-tumor, protection from radiotherapy and chemotherapy damage, sedation, anti-depression, anti-epileptic, anti-Alzheimer's disease, anti-Parkinson's disease, protection from heart and brain ischemia, regulation of blood lipids, lowering blood pressure, lowering blood sugar, protecting the liver, protecting the kidneys, anti-aging, and anti-virus.

[0006] The edible and medicinal part of Ganoderma lucidum is the fruiting body, which is kidney-shaped, semicircular or nearly circular, and the texture of the cap and stipe is leathery, woody or corky, so it is not suitable for direct consumption; generally, the active substances are extracted from Ganoderma lucidum or eaten after being processed by breaking the wall. At present, the production technology of Ganoderma lucidum is mainly based on traditional solid-state cultivation, which is mainly used for the formation of fruiting bodies and the extraction of important active substances. However, Ganoderma lucidum in my country is mainly planted in a scattered manner, with less large-scale cultivation and more traditional cultivation technology; at the same time, solid-state cultivation of Ganoderma lucidum requires a lot of manpower and material resources, and the cultivation cycle is long and requires a lot of time cost. These unfavorable factors lead to weak production capacity, long cycle and uneven quality of Ganoderma lucidum products. There are few types of Ganoderma lucidum products on the market, and the varieties are single. Most of them are sold in the form of whole flowers, slices, spore powder, extracts, etc., and the price is expensive, which limits the public's consumption of health foods. Summary of the invention

[0007] The present invention provides a method for fermenting fresh corn and its application in product processing. One purpose is to solve the problem of few types and single varieties of processed products using fresh corn as raw materials, enrich the types of corn and related products, and meet consumer needs; the second purpose is to solve the problems of single ganoderma products, fruiting bodies not being suitable for direct consumption, and high product prices; the third purpose is to significantly increase the content of ganoderma triterpenes in fermented fresh corn, so that the processed products contain rich active substances of fresh corn and ganoderma, and have better biological activity functions. The fermented fresh corn obtained by the present invention is not only rich in corn nutrition and high content of ganoderma active substances, especially ganoderma triterpenes, so that the fermented fresh corn has the characteristics of rich and balanced nutrition and high content of active substances, and also has multiple biological activities such as anti-oxidation, anti-aging, improving body immunity, regulating blood sugar, blood lipids and blood pressure, protecting liver and kidney, etc.

[0008] The present invention is achieved through the following technical solutions.

[0009] A method for fermenting fresh corn and application thereof in product processing. In order to obtain the fermented fresh corn and apply it to product processing, the operation steps include: S1: harvesting and processing fresh corn cobs to obtain harvested fresh corn cobs, S2: processing the harvested fresh corn cobs to obtain fresh corn crumbs, S3: preparing a fresh corn culture medium with the fresh corn crumbs, S4: culturing ganoderma lucidum strains to obtain ganoderma lucidum fermented seeds, S5: inoculating the ganoderma lucidum fermented seeds into the fresh corn culture medium to obtain fermented fresh corn through fermentation, and S6: drying and crushing the fermented fresh corn to obtain fermented fresh corn powder for application in product processing.

[0010] The fermented fresh corn flour obtained is applied to the processing of various products. For example, the fermented fresh corn flour is added to corn flour products to improve the nutritional value and functional activity of corn flour products, and at the same time improve the color, aroma and taste of corn flour products; the fermented fresh corn flour is added to fresh corn flour, so that the obtained product has the nutrition, taste and function of fresh corn, and at the same time has the nutrition, active substances and functionality of Ganoderma lucidum; the fermented fresh corn flour is added to rice flour to make corresponding products; the fermented fresh corn flour is extracted from active substances and further processed to obtain products; the fermented fresh corn flour is added and applied to the processing of other products; etc.

[0011] The fresh corn includes sweet corn, glutinous corn, sweet and glutinous corn or a mixture of the two.

[0012] The ganoderma lucidum is red ganoderma lucidum or purple ganoderma sinense.

[0013] Specifically, the operation steps are as follows:

[0014] S1: Harvesting and processing fresh corn cobs to obtain fresh corn cobs after harvest

[0015] The picking period of fresh corn cobs is 3-7 days later than the normal harvest period in order to accumulate more dry matter. After the fresh corn cobs are picked, the husks are peeled off and the surface is rinsed with water to remove impurities and debris such as residual husks and corn silk. After being spread out in a dry, ventilated and clean place at room temperature for 10-15 hours, the 3-5 cm part at the tip of the fresh corn cob is removed to obtain the fresh corn cobs after harvest.

[0016] S2: Processing of fresh corn cobs after harvest to obtain fresh corn crumbs

[0017] The harvested fresh corn cobs obtained in S1 are steamed with 100°C steam for 10-15 minutes, taken out, spread out in a clean and ventilated place to cool to room temperature, threshed to obtain fresh corn kernels, and then crushed. The specific operation is to place the fresh corn kernels in a wall breaking machine, start the machine at a medium or low gear and work for 8-15 seconds to obtain broken fresh corn kernels, place the broken fresh corn kernels in a 45-55°C clean forced air drying oven and dry them until the water content of the broken fresh corn kernels is 35-40%, thereby obtaining the fresh corn crumbs.

[0018] S3: Fresh corn crushed to prepare fresh corn culture medium

[0019] The ingredients of the fresh corn culture medium include fresh corn shreds, carrot shreds, terrestrial Issatchen yeast wet bacterial mud, riboflavin and nicotinamide. The specific preparation method is: weigh 60-80 mg of riboflavin and 30-50 mg of nicotinamide, add them to 30-70 g of terrestrial Issatchen yeast wet bacterial mud, and stir them thoroughly; add 150-200 g of carrot shreds thereto, stir them thoroughly again to mix them thoroughly; then add them to 1000-1500 g of fresh corn shreds obtained in step S2, stir them thoroughly to mix them thoroughly, divide them into 100-250 g per 500 mL triangular bottle, sterilize them at 115 ° C for 15 min, and cool them to room temperature to obtain the fresh corn culture medium.

[0020] The method for preparing the shredded carrots comprises removing impurities, washing, draining water from commercially available carrots, cutting them into carrot pieces of 1-2 cm in size, and breaking the carrot pieces to obtain broken carrot pieces. The specific operation comprises placing the carrot pieces in a wall breaking machine, operating the machine at a medium or low gear for 10-20 seconds, and obtaining the broken carrot pieces. The broken carrot pieces are placed in a clean blast drying oven at 45-55° C. and dried until the water content of the broken carrot pieces is 35-40%, and the shredded carrots are obtained.

[0021] The terrestrial Issatchen yeast wet bacterial mud is obtained by inoculating terrestrial Issatchen yeast seed liquid into a liquid citric acid culture medium and culturing it for 24-28 hours, followed by centrifugation.

[0022] The terrestrial Issatchenkia is Issatchenkia terricola WJL-G4, which is deposited in the General Microbiology Center of the China Microbiological Culture Collection Administration Committee, with a deposit number of CGMCC No. 18712. The liquid citric acid medium contains 10-20 g of citric acid, 0.1-0.5 g of MgSO4, and 5-15 g of yeast extract powder per liter of liquid citric acid medium. The method for obtaining the terrestrial Issatchenkia seed liquid is to pick a ring of the terrestrial Issatchenkia terricola WJL-G4 strain stored on the slant, inoculate it in the liquid citric acid medium, and obtain it under the conditions of a temperature of 22-28 ° C, a rotation speed of 120-240 rpm, and a liquid volume ratio of 12-20% (v / v), and a fermentation time of 12-18 h. The culture conditions for obtaining the terrestrial Issatchen yeast wet bacterial mud are: inoculation amount 3-7% (v / v), temperature 22-28°C, rotation speed 120-240 rpm, liquid volume ratio 10-25%, fermentation time 24-48 h. The centrifugation conditions are 8000 rpm, 15 min.

[0023] The citric acid, MgSO4, lutein and nicotinamide, i.e. the raw materials used for fermentation, are all food grade, and the tools and equipment involved are all food grade.

[0024] S4: Cultivate Ganoderma lucidum strains and obtain fermented Ganoderma lucidum seeds

[0025] Take a piece of the Ganoderma lucidum slant culture stored in a 4°C refrigerator, transfer it to a Ganoderma lucidum solid plate culture medium, and culture it at a constant temperature of 22-28°C for 3-7 days to obtain first-class Ganoderma lucidum seeds, cut a piece of the first-class Ganoderma lucidum seeds, transfer it to a Ganoderma lucidum solid plate culture medium again, and culture it at a constant temperature of 22-28°C for 3-7 days to obtain the Ganoderma lucidum fermented seeds.

[0026] The composition of the Ganoderma lucidum solid plate culture medium is 8-15 g of the terrestrial Issatchen yeast wet bacterial mud, 15-25 g of glucose, 150-200 g of potato, 0.1-0.4 g of MgSO4, and 20-25 g of agar per liter, and is obtained by sterilization at 121°C for 15 min. The amount of the Ganoderma lucidum solid plate culture medium in the plate is 12-20 mL per plate, and the plate is inverted after cooling and solidification.

[0027] The potatoes need to be cut into pieces, boiled in water for 30 minutes, and then filtered to obtain the filtrate for use.

[0028] S5: Inoculate fresh corn culture medium with Ganoderma lucidum fermented seeds and ferment to obtain fermented fresh corn

[0029] The fermented ganoderma seeds obtained in step S4 are inoculated into the fresh corn culture medium obtained in step S3 under sterile conditions, stirred evenly with a sterile glass rod, and then cultured in a 22-28° C. incubator for 6-15 days to obtain the fermented fresh corn.

[0030] The inoculation amount of the fermented ganoderma seeds is 3-6 pieces of the fermented ganoderma seeds with a size of 1.5-2 cm × 1.5-2 cm cut into each bottle of the fresh corn culture medium, and after inoculation, a sterile glass rod is used to stir evenly.

[0031] S6: Dry and crush the fermented fresh corn to obtain fermented fresh corn flour for product processing

[0032] The fermented fresh corn obtained in step S5 is freeze-dried or dried at 45-55° C., and crushed to obtain the fermented fresh corn flour.

[0033] The fermented fresh corn flour is used in product processing, and can be directly processed into products, or used in the processing of corn products or related products. For example, it is added to corn flour to make the corn flour have the active substances and nutritional value of Ganoderma lucidum, thereby improving the economic added value of corn processing products; or it is added to fresh corn flour to improve the nutrition and functional activity of fresh corn processing products; or it is used as a main ingredient or auxiliary material in the processing of other products; or it is used to extract the active substances of Ganoderma lucidum, and further processed into health food, health products, cosmetics or pharmaceutical products; etc.

[0034] Advantages of the invention

[0035] The fermentation method of the present invention has the advantages that the fermentation medium is naturally available, cheap, and simple in processing method, the fermentation conditions are mild, the production efficiency is high, the fermentation does not generate waste, and it is green and environmentally friendly. The fermented fresh corn flour obtained by fermentation is rich in nutrition and high in active substance content. It has the nutrition of fresh corn and ganoderma lucidum and has the advantages of improving the body's immunity, adjusting blood sugar and blood lipids, anti-oxidation, anti-aging, protecting the liver and kidneys and other biological activities. The obtained fermented fresh corn flour can be widely used in product processing or food production, can enrich the variety of corn deep-processing products, meet consumer demand, and can also be added to other products, or active substances can be extracted before pharmaceutical product development. Therefore, the fermentation method and application provided by the present invention provide an effective way to extend the fresh corn industry chain and the ganoderma lucidum processing industry chain, and the application prospect is very broad. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The standard curve diagram is the linear relationship between liquid fermentation mycelium biomass and ergosterol.

[0037] Figure 2 The influence of various compound ingredients on fermentation effect.

[0038] Figure 3 The effect of the addition ratio of compound ingredients on the fermentation effect.

[0039] Figure 4 The effects of various external nitrogen sources on fermentation performance.

[0040] Figure 5 The effect of the addition ratio of external nitrogen source on the fermentation effect.

[0041] Figure 6 The influence of various growth factors on fermentation effect.

[0042] Figure 7 The effect of growth factor addition on fermentation effect.

[0043] Figure 8 The effect of culture medium water content on fermentation effect.

[0044] Fig. 9 The effect of culture temperature on fermentation effect.

[0045] Fig.10 The effect of culture medium loading amount on fermentation effect.

[0046] Fig.11 The effect of inoculation size on fermentation effect.

[0047] Fig.12 The effect of culture time on fermentation effect.

[0048] Fig.13 Observation diagram of fermented fresh corn obtained for Example 1-3.

[0049] Fig.14 These are the results of determining the triterpene content and Ganoderma mycelium biomass in Examples 1-3.

[0050] Fig.15 It is fermented fresh corn flour obtained after freeze-drying or drying and crushing. DETAILED DESCRIPTION

[0051] The technical solution of the present invention is further described below in conjunction with specific embodiments, but the present invention is not limited thereto.

[0052] Example 1

[0053] A method for fermenting fresh corn and its application in product processing, the specific implementation scheme is as follows:

[0054] S1: Harvesting and processing fresh corn cobs to obtain fresh corn cobs after harvest

[0055] The picking period of fresh corn cobs is 7 days later than the normal harvest period. After picking the fresh corn cobs, the husks of the fresh corn cobs are peeled off, and the surface is rinsed with clean water to remove the remaining husks, corn silk and other impurities and debris. After being spread out in a cool, dry and clean place for 10 hours, the 3 cm part of the tip of the fresh corn cob is removed to obtain the fresh corn cobs after harvest.

[0056] S2: Processing of fresh corn cobs after harvest to obtain fresh corn crumbs

[0057] The fresh corn cobs obtained in S1 were steamed with 100 ℃ steam for 10 min, cooled to room temperature and then threshed to obtain fresh corn kernels. The fresh corn kernels were placed in a wall breaking machine and operated at gear L5 among medium and low gears for 10 s to obtain broken fresh corn kernels, which were then placed in a 45 ℃ forced air drying oven and dried to a moisture content of 40% to obtain fresh corn crumbs.

[0058] S3: Fresh corn crushed to prepare fresh corn culture medium

[0059] The ingredients of the fresh corn culture medium include fresh corn shreds, carrot shreds, terrestrial Issatchengen wet culture mud, food grade riboflavin and food grade nicotinamide.

[0060] The commercially available carrots were cleaned and cut into 1 cm carrot pieces, and the carrot pieces were placed in a wall-breaking machine and operated at the L6 gear in the medium-low gear for 20 s to obtain broken carrot pieces. The broken carrot pieces were placed in a 55 ℃ clean air drying oven and dried until the water content of the broken carrot pieces was 40%, thereby obtaining carrot pieces.

[0061] A loop of Issatchenkia terricola WJL-G4 strain stored on a slant was picked and inoculated into a liquid citric acid medium containing 20 g / L food-grade citric acid, 0.1 g / L food-grade MgSO4, and 5 g / L food-grade yeast extract powder. The culture was fermented for 12 h at a temperature of 28 °C, a rotation speed of 140 rpm, and a liquid volume ratio of 12% (v / v) to obtain the Issatchenkia terricola seed liquid. The Issatchenkia terricola seed liquid was inoculated into a liquid citric acid medium with a liquid volume ratio of 15% at an inoculation rate of 3% (v / v). After fermentation for 48 h at a temperature of 28 °C and a rotation speed of 140 rpm, the culture was centrifuged at 8000 rpm for 15 min to obtain the Issatchenkia terricola wet bacterial mud.

[0062] Weigh 60 mg of food-grade riboflavin and 30 mg of food-grade nicotinamide, add them to 30 g of terrestrial Issatchengen wet bacterial mud, and stir and mix them evenly; then add 150 g of shredded carrots, stir and mix them evenly; then add 1000 g of the shredded fresh corn obtained in step S2, stir and mix them evenly; package, put 200 g in each 500 mL triangular bottle, sterilize at 115 ° C for 15 min, and cool to room temperature to obtain a fresh corn culture medium.

[0063] S4: Cultivate Ganoderma lucidum strains and obtain fermented red Ganoderma lucidum seeds

[0064] Take 200 g of peeled potatoes, add 800 mL of water, boil for 30 min, filter to obtain filtrate, add 8 g of terrestrial Issatchen yeast wet bacterial mud obtained in step S3, 15 g of food-grade glucose, 0.1 g of food-grade MgSO4, and 20 g of food-grade agar powder, adjust the volume to 1000 mL, stir evenly, sterilize at 121 ° C for 15 min, pour the plate after appropriate cooling, and obtain a solid plate medium of Ganoderma lucidum. Take a piece of the red Ganoderma lucidum slant strain stored in a 4 ° C refrigerator, pick it, transfer it to the solid plate medium of Ganoderma lucidum, and culture it at a constant temperature of 28 ° C for 7 days to obtain a first-level red Ganoderma lucidum seed, cut a piece of the first-level red Ganoderma lucidum seed, transfer it to the solid plate medium of Ganoderma lucidum again, and culture it at a constant temperature of 28 ° C for 7 days to obtain the fermented red Ganoderma lucidum seed.

[0065] S5: Inoculate the fresh corn culture medium with Ganoderma lucidum fermented seeds and ferment to obtain fermented fresh corn

[0066] Cut the fermented red ganoderma lucidum seeds obtained in step S4 into 6 pieces of 1.5 cm×1.5 cm under sterile conditions, inoculate them into 1 bottle of fresh corn culture medium obtained in step S3, inoculate 6 pieces into each bottle of fresh corn culture medium, stir evenly with a sterile glass rod, and then culture in a 26°C incubator for 6 days to obtain fermented fresh corn.

[0067] S6: Dry and crush the fermented fresh corn to obtain fermented fresh corn flour for product processing

[0068] The fermented fresh corn obtained in step S5 is freeze-dried and crushed to obtain the fermented fresh corn flour.

[0069] The fermented fresh corn flour is added to corn flour at a mass ratio of 10 parts of the fermented fresh corn flour per 100 parts of corn flour to obtain a corn flour product.

[0070] Example 2

[0071] A method for fermenting fresh corn and its application in product processing, the specific implementation scheme is as follows:

[0072] S1: Harvesting and processing fresh corn cobs to obtain fresh corn cobs after harvest

[0073] The picking period of fresh corn cobs is 3 days later than the normal harvest period. After picking the fresh corn cobs, the husks of the fresh corn cobs are peeled off, and the surface is rinsed with water to remove impurities and debris such as residual husks and corn silk. After being spread out in a cool, dry, ventilated and clean place for 12 hours, the 5 cm part of the tip of the fresh corn cobs is removed to obtain the fresh corn cobs after harvest.

[0074] S2: Processing of fresh corn cobs after harvest to obtain fresh corn crumbs

[0075] The harvested fresh corn cobs obtained in S1 are steamed with 100°C steam for 15 min, cooled to room temperature, and threshed after the surface moisture evaporates to obtain fresh corn kernels. The fresh corn kernels are placed in a wall breaking machine and operated at a medium-low gear L6 for 15 seconds to obtain broken fresh corn kernels, which are then placed in a 45°C forced air drying oven and dried to a moisture content of 40% to obtain fresh corn crumbs.

[0076] S3: Fresh corn crushed to prepare fresh corn culture medium

[0077] The ingredients of the fresh corn culture medium include fresh corn shreds, carrot shreds, terrestrial Issatchengen wet culture paste, riboflavin and nicotinamide.

[0078] The commercially available carrots were cleaned and cut into 2 cm carrot pieces, and the carrot pieces were placed in a wall-breaking machine, and the machine was operated at the L5 gear in the medium-low gear for 15 s to obtain broken carrot pieces. The broken carrot pieces were placed in a clean blast drying oven at 45 °C and dried until the water content of the broken carrot pieces was 35%, thereby obtaining carrot pieces.

[0079] A ring of Issatchenkia terricola WJL-G4 strain stored on a slant was picked and inoculated into a liquid citric acid medium containing 20 g / L food-grade citric acid, 0.1 g / L food-grade MgSO4, and 5 g / L food-grade yeast extract powder. The culture was fermented for 18 h at a temperature of 28 °C, a rotation speed of 140 rpm, and a liquid volume ratio of 12% (v / v) to obtain the Issatchenkia terricola seed liquid. The Issatchenkia terricola seed liquid was inoculated into a liquid citric acid medium with a liquid volume ratio of 20% at an inoculation rate of 5% (v / v). After fermentation for 48 h at a temperature of 28 °C and a rotation speed of 140 rpm, the wet bacterial mud of Issatchenkia terricola was obtained.

[0080] Weigh 75 mg of food-grade riboflavin and 50 mg of food-grade nicotinamide, add them to 70 g of terrestrial Issatchengen wet bacterial mud, and stir and mix them evenly; then add 200 g of carrot shreds thereto, stir and mix them evenly; then add all of them to 1500 g of fresh corn shreds obtained in step S2, stir and mix them evenly; package, 250 g per 500 mL triangular bottle, sterilize at 115 ° C for 15 min, and cool to room temperature to obtain a fresh corn culture medium.

[0081] S4: Cultivate purple Ganoderma lucidum strains and obtain purple Ganoderma lucidum fermented seeds

[0082] Take a piece of the purple Ganoderma lucidum slant strain stored in a 4°C refrigerator, transfer it to a Ganoderma lucidum solid plate culture medium, and culture it at a constant temperature of 25°C for 3 days to obtain a first-level purple Ganoderma lucidum seed, cut a piece of the first-level purple Ganoderma lucidum seed, transfer it to a Ganoderma lucidum solid plate culture medium again, and culture it at a constant temperature of 25°C for 3 days to obtain the purple Ganoderma lucidum fermented seeds.

[0083] The composition of the Ganoderma lucidum solid plate culture medium is that each liter contains 15 g of the terrestrial Issatchengen wet bacterial mud, 25 g of glucose, 150 g of potato, 0.4 g of MgSO4, and 25 g of agar; the preparation method is that the potato is boiled with an appropriate amount of water for half an hour, the filtrate is filtered, other substances are added, the volume is fixed to 1000 mL, and then sterilized at 121°C for 15 min.

[0084] S5: Inoculate fresh corn culture medium with Ganoderma lucidum fermented seeds and ferment to obtain fermented fresh corn

[0085] Cut 4 pieces of 2 cm×2 cm in size from the fermented purple Ganoderma lucidum seeds obtained in step S4, and inoculate all of them into 1 bottle of the fresh corn culture medium obtained in step S3 under sterile conditions, for a total of 4 bottles. Each bottle is stirred evenly with a sterile glass rod, and then cultured in an incubator at 22° C. for 12 days to obtain the fermented fresh corn.

[0086] S6: Dry and crush the fermented fresh corn to obtain fermented fresh corn flour for product processing

[0087] The fermented fresh corn obtained in step S5 is dried at 55° C. and crushed to obtain the fermented fresh corn flour.

[0088] The fermented fresh corn flour is added to fresh corn flour at a mass ratio of 50 parts of the fermented fresh corn flour per 100 parts of fresh corn flour to obtain a product.

[0089] Example 3

[0090] A method for fermenting fresh corn and its application in product processing, the specific implementation scheme is as follows:

[0091] S1: Harvesting and processing fresh corn cobs to obtain fresh corn cobs after harvest

[0092] The picking period of fresh corn cobs is 5 days later than the normal harvest period. After picking the fresh corn cobs, the husks of the fresh corn cobs are peeled off, and the surface is rinsed with water to remove the remaining husks, corn silk and other impurities and debris. After being spread out in a clean, dry and ventilated place for 15 hours, the 4 cm part of the tip of the fresh corn cobs is removed to obtain the fresh corn cobs after harvest.

[0093] S2: Processing of fresh corn cobs after harvest to obtain fresh corn crumbs

[0094] The harvested fresh corn cobs obtained in S1 are steamed with 100°C steam for 12 min, cooled to room temperature and then threshed to obtain fresh corn kernels, the fresh corn kernels are placed in a wall breaking machine, and the machine is operated at a medium-low gear L4 for 10 s to obtain broken fresh corn kernels, the broken fresh corn kernels are placed in a 50°C oven and dried to a moisture content of 35%, to obtain the fresh corn crumbs.

[0095] S3: Fresh corn crushed to prepare fresh corn culture medium

[0096] The fresh corn culture medium comprises fresh corn shreds, carrot shreds, terrestrial Issatchenia wet bacterial mud, riboflavin and nicotinamide.

[0097] The commercially available carrots were cleaned and cut into 2 cm carrot pieces, and the carrot pieces were placed in a wall-breaking machine, and the machine was operated at the L4 gear in the medium-low gear for 10 s to obtain broken carrot pieces. The broken carrot pieces were placed in a 45 ℃ clean air drying oven and dried until the water content of the broken carrot pieces was 40%, thereby obtaining carrot pieces.

[0098] A ring of Issatchenkia terricola WJL-G4 strain stored on a slant was picked and inoculated into a liquid citric acid medium containing 20 g / L food-grade citric acid, 0.1 g / L food-grade MgSO4, and 5 g / L food-grade yeast extract powder. The culture was fermented for 18 h at a temperature of 28 °C, a rotation speed of 140 rpm, and a liquid volume ratio of 12% (v / v) to obtain the Issatchenkia terricola seed liquid. The Issatchenkia terricola seed liquid was inoculated into a liquid citric acid medium with a liquid volume ratio of 20% at an inoculation rate of 5% (v / v). After fermentation for 48 h at a temperature of 28 °C and a rotation speed of 140 rpm, the wet bacterial mud of Issatchenkia terricola was obtained.

[0099] In addition, 69 mg of food-grade riboflavin and 40 mg of food-grade nicotinamide were weighed and added to 50 g of terrestrial Issatchengen wet bacterial slurry, and the mixture was thoroughly stirred and mixed; then all of the mixture was added to 150 g of shredded carrots, and the mixture was thoroughly stirred and mixed; then 1500 g of shredded fresh corn obtained in step S2 was added, and the mixture was thoroughly stirred and mixed; the mixture was packaged in 500 mL triangular bottles, 150 g each, and sterilized at 115°C for 15 min, and cooled to room temperature to obtain a fresh corn culture medium.

[0100] S4: Cultivate red Ganoderma lucidum strains and obtain fermented red Ganoderma lucidum seeds

[0101] Take a piece of the red Ganoderma lucidum slant culture stored in a 4°C refrigerator, transfer it to a Ganoderma lucidum solid plate culture medium, and culture it at a constant temperature of 25°C for 5 days to obtain the first-level red Ganoderma lucidum seeds. Cut a piece of the first-level red Ganoderma lucidum seeds, transfer it to a Ganoderma lucidum solid plate culture medium again, and culture it at a constant temperature of 25°C for 5 days to obtain the red Ganoderma lucidum fermented seeds.

[0102] The composition of the Ganoderma lucidum solid plate culture medium is that per liter it contains 12 g of the terrestrial Issatchen yeast wet bacterial mud, 20 g of glucose, 150 g of potato, 0.25 g of MgSO4, and 20 g of agar. The 150 g of potato needs to be boiled with an appropriate amount of water for 30 minutes in advance and then filtered to obtain the filtrate for use. The Ganoderma lucidum solid plate culture medium is sterilized at 121°C for 15 minutes.

[0103] S5: Inoculate the fresh corn culture medium with Ganoderma lucidum fermented seeds and ferment to obtain fermented fresh corn

[0104] The fermented red ganoderma seeds obtained in step S4 are inoculated into the fresh corn culture medium obtained in step S3 under sterile conditions, stirred evenly with a sterile glass rod, and then cultured in a 25° C. incubator for 8 days to obtain the fermented fresh corn.

[0105] The inoculation amount of the fermented red ganoderma seeds is to inoculate 5 fermented red ganoderma seeds of 1.5 cm×2 cm in size into each bottle of the fresh corn culture medium, and after inoculation, use a sterile glass rod to stir evenly.

[0106] S6: Dry and crush the fermented fresh corn to obtain fermented fresh corn flour for product processing

[0107] The fermented fresh corn obtained in step S5 is dried at 45° C. and crushed to obtain the fermented fresh corn flour.

[0108] The fermented fresh corn flour is added to rice flour at a mass ratio of 30 parts of the fermented fresh corn flour per 100 parts of rice flour to obtain a product.

[0109] Example 4

[0110] Optimization of culture medium formulation for fresh corn.

[0111] This example uses red ganoderma lucidum as the fermentation strain. Take a piece of red ganoderma lucidum slant strain stored in a refrigerator at 4°C, transfer it to a PDA solid plate culture medium, and culture it at a constant temperature of 22-28°C for 4 days, then transfer it to a PDA solid plate culture medium again, and culture it at a constant temperature of 22-28°C for 4 days to obtain the red ganoderma lucidum fermentation strain of this example.

[0112] Fresh corn crumbs alone were used as the control fermentation medium, and the triterpenoid content of Ganoderma lucidum and the biomass of Ganoderma lucidum mycelium were used as the judgment indicators to screen the effects of adding complex ingredients, external nitrogen sources, growth factors, etc. to fresh corn crumbs on the fermentation effect.

[0113] (1) First, establish the relationship between mycelium biomass and ergosterol content.

[0114] A soybean-sized mycelium of Ganoderma lucidum was picked from the solid slant medium and transferred to the solid plate medium of Ganoderma lucidum. After culturing in a constant temperature incubator at 25 ℃ for 3-7 days, a piece was cut and transferred to the liquid medium of Ganoderma lucidum. The culture was carried out in a 250mL triangular bottle with a liquid volume of 50 mL, 150 rpm, and constant temperature of 25 ℃ for 12 days. The fermentation was stopped on the 3rd, 5th, 7th, 9th, 11th, and 13th days of culture, and the mycelium biomass and ergosterol content in the triangular bottle were determined. The results are shown in Table 1. Figure 1 As shown, a linear equation between Ganoderma lucidum mycelium biomass and ergosterol content was established.

[0115] The determination method of the Ganoderma lucidum mycelium obtained by liquid fermentation in this step is determined by weight method, and the determination method of ergosterol is determined by ultraviolet spectrophotometry.

[0116] The established linear equation is as follows:

[0117] y = 3.8963x + 0.588, R² = 0.9982

[0118] Where x represents the dry weight of Ganoderma mycelium biomass in g, and y represents the ergosterol content in mg.

[0119] Since it is difficult to separate mycelium in solid-state fermentation, this formula is used to calculate the biomass of Ganoderma mycelium in fermented fresh corn.

[0120] (2) Screening of compound ingredients

[0121] Only fresh corn shreds in the culture medium were used as the control fermentation medium. Fresh corn shreds were obtained by referring to the method of Example 3. Based on 1000 g of fresh corn shreds, 200 g of bran, soybean meal, pumpkin shreds, tomato shreds, carrot shreds, peanut shreds, sweet potato shreds, barley, wheat, sorghum rice, coix seeds, and millet were added and sterilized to obtain the culture medium. Bran, soybean meal, barley, wheat, sorghum rice, coix seeds, and millet were all added with water in advance to adjust the water content by mass ratio to 40%; pumpkin shreds, tomato shreds, carrot shreds, peanut shreds, and sweet potato shreds were prepared by referring to the method for preparing carrot shreds in Example 3, and the water content by mass ratio was adjusted to 40% respectively; pumpkin was prepared with seedless pumpkin flesh. After adding different composite ingredients, 150 g of culture medium was added to each 500 mL triangular flask.

[0122] The culture conditions are as follows: 3 pieces of mycelium of 1.5 cm × 1.5 cm in size were cut from the fermented strain of red Ganoderma lucidum in this example under sterile conditions, placed in a triangular flask, stirred evenly with a sterile glass rod, and then cultured in a 25°C incubator for 12 days. After the culture was completed, the ergosterol content in the fermentation product was determined to calculate the biomass of Ganoderma lucidum mycelium, the triterpene content was determined (i.e., the triterpene content of Ganoderma lucidum was determined by ultraviolet spectrophotometry), and the effects of various compound ingredients on the fermentation effect were compared. The results are as follows: Figure 2 shown.

[0123] Depend on Figure 2 It can be seen that when 20% of various composite ingredients were added to the fresh corn crumbs, different fermentation results appeared. Among them, the content of mycelium and triterpenes of red Ganoderma lucidum in the samples with coix seed, pumpkin crumbs, tomato crumbs and sweet potato crumbs decreased significantly after the fermentation. It was found by observing the triangular flask that the culture medium with coix seed, pumpkin crumbs, tomato crumbs and sweet potato crumbs collapsed and the growth of red Ganoderma lucidum was poor. Therefore, it was judged that these three composite ingredients were not conducive to fermentation. The growth of Ganoderma lucidum was most significantly inhibited after the addition of peanut crumbs. In the culture medium with bran, soybean meal, carrot crumbs, barley, wheat, sorghum rice and millet, the growth of red Ganoderma lucidum was better than that of the control group, and the mycelium biomass was higher than that of the control group, indicating that the addition of these composite ingredients was beneficial to the growth of Ganoderma lucidum. In terms of triterpene content, the triterpene content was significantly increased after the addition of carrot crumbs, which was significantly higher than that of other groups. Therefore, from the perspective of triterpene content and mycelium biomass, the addition of carrot crumbs was the best fermentation composite ingredient.

[0124] (3) Screening of the amount of compound ingredients added

[0125] The triterpenoid content of Ganoderma lucidum and the biomass of Ganoderma lucidum mycelium were used as the judgment indicators. The culture medium containing only fresh corn shreds was used as the control fermentation medium. The mass percentages of carrot shreds added to the fresh corn shreds were screened to be 5%, 10%, 15%, 20%, and 25%, respectively. The inoculation and culture conditions in Example (2) were adopted. Each 500 mL triangular flask was filled with 150 g of culture medium. After the culture was completed, the ergosterol content was measured to calculate the biomass of Ganoderma lucidum mycelium, the triterpenoid content was measured, and the effects of various addition ratios on the fermentation effect were compared. The results are as follows: Figure 3 shown.

[0126] Depend on Figure 3 It can be seen that when the added mass percentage was 10%, 15%, 20% and 25% respectively, the growth of Ganoderma lucidum was better than that of other groups, and the mycelium biomass was higher. When the added mass percentage was 10%, 15% and 20% respectively, the triterpene content was significantly higher than that of other groups. Therefore, from the two aspects of triterpene content and mycelium biomass, adding carrot shreds at 10%-20% is the best addition amount.

[0127] (4) Screening of external nitrogen sources

[0128] A culture medium supplemented with fresh corn shreds and 15% shredded carrots by mass of the fresh corn shreds was used as a control fermentation medium. The fresh corn shreds and shredded carrots were obtained according to the method of Example 3. Based on 1000 g of fresh corn shreds in the culture medium, 20 g of yeast extract powder and peptone, 40 g of Saccharomyces cerevisiae wet bacterial sludge and Issatchenko spp. WJL-G4 wet bacterial sludge were added, respectively, and the culture medium was sterilized to obtain the culture medium.

[0129] The method for obtaining the wet bacterial mud of Saccharomyces cerevisiae is as follows: a ring of the Saccharomyces cerevisiae strain stored on the slant is picked up, inoculated into the YPD medium, and fermented for 12 h at a temperature of 28 °C, a rotation speed of 140 rpm, and a liquid volume ratio of 12% (v / v) to obtain the Saccharomyces cerevisiae seed liquid. The Saccharomyces cerevisiae seed liquid is inoculated into a YPD medium with a liquid volume ratio of 15% at an inoculation rate of 3% (v / v), and fermented for 48 h at a temperature of 28 °C and a rotation speed of 140 rpm, and then centrifuged at 8000 rpm for 15 min to obtain the wet bacterial mud of Saccharomyces cerevisiae.

[0130] The method for obtaining the wet bacterial mud of Issatchenkia terricola WJL-G4 is as follows: a ring of Issatchenkia terricola WJL-G4 strains stored on a slant is picked and inoculated into a liquid citric acid medium containing 20 g / L food-grade citric acid, 0.1 g / L food-grade MgSO4, and 5 g / L food-grade yeast extract powder, and fermented for 12 h at a temperature of 28 °C, a rotation speed of 140 rpm, and a liquid volume ratio of 12% (v / v) to obtain the terrestrial Issatchenkia seed liquid. The terrestrial Issatchenkia seed liquid is inoculated into a liquid citric acid medium with a liquid volume ratio of 15% at an inoculation rate of 3% (v / v), and fermented for 48 h at a temperature of 28 °C and a rotation speed of 140 rpm, and then centrifuged at 8000 rpm for 15 min to obtain the terrestrial Issatchenkia wet bacterial mud.

[0131] The culture medium with different external nitrogen sources was added, and the inoculation and culture conditions in Example (2) were adopted. Each 500 mL Erlenmeyer flask was filled with 150 g of culture medium. After the culture was completed, the triterpene content was determined and the biomass of Ganoderma mycelium was calculated. The effects of various external nitrogen sources on the fermentation effect were compared. The results are as follows: Figure 4 shown.

[0132] Depend on Figure 4 It can be seen that the group with 40g of terrestrial Issatchengen wet mud had the highest triterpene content, which was significantly higher than that of other groups. Therefore, it was concluded that the addition of 40g of terrestrial Issatchengen wet mud significantly promoted the synthesis of triterpene substances.

[0133] (5) Screening of the amount of added nitrogen source

[0134] The triterpenoid content of Ganoderma lucidum and the biomass of Ganoderma lucidum mycelium were used as the judgment indicators. The culture medium was supplemented with fresh corn powder and 15% of carrot powder by mass of the fresh corn powder as the control fermentation medium. The fresh corn powder and carrot powder were obtained according to the method of Example 3. 1000 g of fresh corn powder in the culture medium was used as the calculation basis. The wet bacterial mud of terrestrial Issatchenia yeast was added in an amount of 10, 20, 30, 40, 50, 60, 70, 80, and 90 g, respectively. The inoculation and culture conditions in Example (2) were adopted. 150 g of culture medium was added to each 500 mL triangular flask. After the culture was completed, the ergosterol content was measured to calculate the biomass of Ganoderma lucidum mycelium, the triterpenoid content was measured, and the effects of various addition ratios on the fermentation effect were compared. The results are as follows: Figure 5 shown.

[0135] Depend on Figure 5It can be seen that with 1000 g of fresh corn crumbs in the culture medium as the calculation basis, adding 10-80 g of Issatchengensis wet mud is beneficial to the synthesis of triterpenoids. When the addition amount is 20, 30, 40, 50, 60, and 70 g, Ganoderma lucidum grows well, and the triterpene content is higher than that of other groups. Therefore, adding 20-70 g of Issatchengensis wet mud to 1000 g of fresh corn crumbs is the best addition amount.

[0136] (6) Screening of growth factors

[0137] 1000 g of fresh corn powder in the culture medium was used as the calculation basis, 150 g of carrot powder was added, 40 g of terrestrial Issatchengen wet bacterial mud was added, and 200 mg of thiamine, riboflavin, nicotinamide, pantothenic acid, biotin, pyridoxine, lipoic acid, and cyanocobalamin were added respectively, and the culture medium was obtained by sterilization; the inoculation and culture conditions in Example (2) were adopted, and 150 g of culture medium was respectively filled in each 500 mL conical flask. After the culture was completed, the ergosterol content was measured to calculate the biomass of Ganoderma mycelium, the triterpene content was measured, and the effects of various growth factors on the fermentation effect were compared. The results are as follows: Figure 6 shown.

[0138] Depend on Figure 6 It can be seen that when nicotinamide or riboflavin is added, it is beneficial to increase the content of triterpenes, while other growth factors have no obvious effect. Therefore, further screening of the amount of nicotinamide and riboflavin added was carried out.

[0139] (7) Screening of the amount of growth factor added

[0140] 1000 g of fresh corn powder in the culture medium was used as the calculation basis, 150 g of carrot powder was added, and 40 g of terrestrial Issatchengen wet bacterial mud was added as the control group. The treatment groups were respectively added with 20, 40, 60, 80, 100, 150, 200, and 250 mg of riboflavin, or 5, 20, 35, 50, 65, 80, 100, 150, 200, and 250 mg of nicotinamide. The culture medium was divided into 500 mL Erlenmeyer flasks with 150 g of culture medium, and sterilized to obtain the culture medium. The inoculation and culture conditions in Example (2) were used. After the culture was completed, the ergosterol content was determined to calculate the biomass of Ganoderma mycelium, the triterpene content was determined, and the effects of different growth factor addition amounts on the fermentation effect were compared. The results are as follows. Figure 7 shown.

[0141] Depend on Figure 7As can be seen from the middle left figure, when the riboflavin addition is 60 mg or more, the triterpene content is significantly increased compared with other additions, but when more riboflavin than 60 mg is added, there is no greater effect on the increase in triterpene content. Therefore, considering the triterpene content and cost, the optimal addition of riboflavin is 60-80 mg. Figure 7 As can be seen from the middle right figure, when the amount of niacinamide added is greater than or equal to 20 mg, the growth of Ganoderma lucidum and the triterpene content are both good. Considering the triterpene content and cost, the optimal amount of niacinamide added is 20-50 mg.

[0142] Example 5

[0143] Optimization of optimal fermentation culture conditions for fresh corn.

[0144] This example uses red ganoderma lucidum as the fermentation strain.

[0145] Based on 1000 g of fresh corn crushed in the culture medium, 150 g of carrot crushed and 70 g of Issatchengensis wet mud were added, and then 60 mg of riboflavin and 35 mg of nicotinamide were added respectively to screen the effects of culture medium moisture content, culture temperature, culture medium filling amount, inoculation amount, culture time, etc. on the fermentation effect.

[0146] (1) Screening of water content of culture medium

[0147] Growth factors were screened by fermenting red ganoderma lucidum (Ganoderma lucidum). 1000 g of fresh corn shreds in the culture medium was used as the calculation basis. 150 g of carrot shreds and 70 g of terrestrial Issatchengensis wet bacterial mud were added. 60 mg of riboflavin and 35 mg of nicotinamide were added respectively. The water content of the mixture of fresh corn shreds and carrot shreds in the culture medium was adjusted to 30%, 35%, 40%, 42.5%, 45%, 47.5%, 50% and 55% by weight. The culture medium was divided into 500 mL conical flasks with 150 g of culture medium respectively, and sterilized to obtain the culture medium. The inoculation and culture conditions in Example (2) were used. After the culture was completed, the ergosterol content was measured to calculate the biomass of Ganoderma lucidum mycelium, the triterpene content was measured, and the effects of different culture medium water contents on the fermentation effect were compared. The results are as follows: Figure 8 shown.

[0148] Depend on Figure 8 It can be seen that when the moisture content of fresh corn and carrot shreds is 35-40%, the fermentation effect is better, and the mycelium biomass and triterpene content are higher than those of other moisture content groups. Therefore, it is appropriate to determine that the moisture content of fresh corn and carrot shreds is 35%-40%.

[0149] (2) Screening of culture temperature

[0150] 1000 g of fresh corn shreds in the culture medium was used as the calculation basis, 150 g of carrot shreds, 70 g of Issatchengen terrestrial wet bacterial mud, 60 mg of riboflavin, and 35 mg of nicotinamide were added respectively, and the water content of the mixture of fresh corn shreds and carrot shreds in the culture medium was adjusted to 35% by mass. 150 g of culture medium was placed in each 500 mL conical flask, and the culture medium was sterilized to obtain the culture medium; the culture temperature was selected to be 22, 25, 28, 31, and 34 °C, and the other conditions were the inoculation and culture conditions in step (2) of Example 4. After the culture was completed, the ergosterol content was determined to calculate the biomass of Ganoderma mycelium, the triterpene content was determined, and the effects of different culture temperatures on the fermentation effect were compared. The results are as follows: Fig. 9 shown.

[0151] Depend on Fig. 9 It can be seen that when the culture temperature is selected at 22-28 ℃, the growth of Ganoderma lucidum and the content of triterpenes are better, so 22-28 ℃ is selected as the optimal culture temperature.

[0152] (3) Screening of culture medium filling amount

[0153] Taking 1000 g of fresh corn shreds in the culture medium as the calculation basis, 150 g of carrot shreds, 70 g of Issatchengensis wet bacterial mud, and 60 mg of riboflavin and 35 mg of nicotinamide were added respectively, and the water content of the mixture of fresh corn shreds and carrot shreds in the culture medium was adjusted to 35% by mass. The culture medium was divided into 500 mL conical flasks with 100, 150, 200, 250, and 300 g of culture medium, respectively, and sterilized to obtain the culture medium. The other culture conditions adopted the inoculation and culture conditions in step (2) of Example 4. After the culture was completed, the ergosterol content was measured to calculate the biomass of Ganoderma mycelium, the triterpene content was measured, and the effects of different culture medium loading amounts on the fermentation effect were compared. The results are as follows: Fig.10 shown.

[0154] Depend on Fig.10It can be seen that when 100, 150, 200, and 250 g of culture medium were filled per 500 mL triangular flask, the triterpenoid and mycelium biomass of Ganoderma lucidum were good on the 12th day, but the growth rate of each flask was different. The smaller the filling amount, the faster the growth rate. When the filling amount was 100 g, the mycelium on the 7th and 8th day of fermentation was full of the culture medium and the triangular flask; when the filling amount was 150 and 200 g, the mycelium on the 9th and 10th day of fermentation was full of the culture medium and the triangular flask; when the filling amount was 250 and 300 g, the mycelium on the 11th and 13th day of fermentation was full of the culture medium and the triangular flask; but when the filling amount was 300 g, stirring was difficult. At the same time, the distance between the culture medium and the triangular flask mouth after stirring was close, which was easy to cause contamination, and the fermentation time was also significantly prolonged. From the perspective of triterpene content, the triterpene content showed a downward trend when the filling amount was large. Therefore, considering the triterpene content, fermentation efficiency and yield, it is appropriate to fill 100-250 g per 500 mL conical flask.

[0155] (4) Screening of inoculum size

[0156] 1000 g of fresh corn shreds in the culture medium was used as the calculation basis, 150 g of carrot shreds, 70 g of Issatchengen terrestrial wet bacterial mud, 60 mg of riboflavin, and 35 mg of nicotinamide were added respectively, and the water content of the mixture of fresh corn shreds and carrot shreds in the culture medium was adjusted to 35% by mass. 150 g of culture medium was placed in each 500 mL conical flask, and the culture medium was obtained by sterilization. The inoculation amount was selected from 1, 2, 3, 4, 5, and 6 pieces of 1.5 cm×1.5 cm blocks cut out. The other conditions adopted the inoculation and culture conditions in step (2) of Example 4. After the culture was completed, the ergosterol content was determined to calculate the biomass of Ganoderma mycelium, the triterpene content was determined, and the effects of different inoculation amounts on the fermentation effect were compared. The results are as follows. Fig.11 shown.

[0157] Depend on Fig.11 It can be seen that when the inoculation amount is 3-6 pieces, the triterpenoid and mycelium growth are higher than other inoculation amounts; from the perspective of mycelium growth, the more blocks inoculated, the faster the mycelium grows. When 6 blocks are inoculated, the mycelium basically covers the surface of the culture medium on the 5th to 6th day of fermentation. When 1 block is inoculated, it takes 10-12 days for the mycelium to basically cover the surface of the culture medium. In order to improve the fermentation efficiency and achieve the fermentation effect as soon as possible, 3-6 blocks are selected as the optimal inoculation amount.

[0158] (5) Screening of culture time

[0159] Taking 1000 g of fresh corn shreds in the culture medium as the calculation basis, 150 g of carrot shreds, 70 g of terrestrial Issatchengen wet bacterial mud, 60 mg of riboflavin, and 35 mg of nicotinamide were added respectively, and the water content of the mixture of fresh corn shreds and carrot shreds in the culture medium was adjusted to 35% by mass. The culture medium was packaged in such a way that 150 g of the culture medium was placed in each 500 mL conical flask, and the culture medium was sterilized to obtain the culture medium. The culture time was selected to be 4, 6, 8, 10, 12, 15, and 20 d, and the other conditions were the inoculation and culture conditions in step (2) of Example 4. After the culture was completed, the ergosterol content was determined to calculate the biomass of Ganoderma mycelium, the triterpene content was determined, and the effects of different culture times on the fermentation effect were compared. The results are as follows: Fig.12 shown.

[0160] Depend on Fig.12 It can be seen that when the culture time is more than 6 days, the triterpenoids accumulate better. In order to achieve the best fermentation effect, the culture time can be extended to 12-15 days. According to the biomass of Ganoderma mycelium and triterpenoid content, combined with the time cost, 6-15 days was selected as the optimal culture time.

[0161] The method for obtaining fresh corn shreds, carrot shreds, and Issatchen yeast wet bacterial slurry in this example is the same as that in Example 3 unless otherwise specified. All materials or substances used are food grade.

[0162] Example 6

[0163] The fermented fresh corn obtained in Examples 1-3 was observed, the active substances were determined, and fermented fresh corn flour was obtained.

[0164] Example 1-3 Fermentation of fresh corn Fig.13 As shown in FIG. 1 , Ganoderma lucidum grew well on the fresh corn culture medium, and mycelium covered the entire triangular flask. The fermented fresh corns were dried according to the methods described in Examples 1-3, and the triterpene content and Ganoderma lucidum mycelium biomass were measured. The results were as follows: Fig.14 shown.

[0165] Depend on Fig.14 It can be seen that the triterpene contents in the fermented fresh corn flour of Examples 1-3 after fermentation were 17.54±0.51, 19.22±0.92, and 19.59±0.50 mg / g, respectively, and the mycelium biomass was 64.46±3.24, 70.17±2.46, and 72.13±3.17 mg / g, respectively. The obtained fermented fresh corn flour contains rich triterpene active substances, which can be used in product production to effectively improve product quality.

[0166] The fermented fresh corn flour obtained by freeze-drying or drying at 55 ℃ and crushing is shown in Fig.15 As shown, Fig.15The left one is the fermented fresh corn flour that is dried and crushed at 55℃. Fig.15 On the right is freeze-dried and crushed fermented fresh corn flour. As can be seen from the picture, the fermented fresh corn flour is delicate and fluffy turmeric yellow, and has a strong mushroom aroma of large fungi.

[0167] The above descriptions are only some embodiments of the present invention and are not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the contents of the specification of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for fermenting fresh corn and its application in product processing, characterized in that: The operation steps include: S1: harvesting and processing fresh corn cobs to obtain harvested fresh corn cobs, S2: processing the harvested fresh corn cobs to obtain fresh corn crumbs, S3: preparing a fresh corn culture medium with the fresh corn crumbs, S4: culturing ganoderma lucidum strains to obtain fermented ganoderma lucidum seeds, S5: inoculating the fresh corn culture medium with the fermented ganoderma lucidum seeds to obtain fermented fresh corn by fermentation, and S6: drying and crushing the fermented fresh corn to obtain fermented fresh corn powder for use in product processing; the fresh corn includes sweet corn, glutinous corn, or a mixture of sweet and glutinous corns; and the ganoderma lucidum is red ganoderma lucidum (Ganoderma lucidum) or purple ganoderma lucidum (Ganoderma sinense).

2. The method for fermenting fresh corn according to claim 1, characterized in that: The S1: harvesting and processing of fresh corn cobs to obtain fresh corn cobs after harvest is as follows: the picking period of fresh corn cobs is 3-7 days later than the normal harvest period. After the fresh corn cobs are picked, the husks of the fresh corn cobs are peeled off, and the surface is rinsed with water to remove impurities and debris such as residual husks and corn silk. After being spread out in a dry, ventilated and clean place at room temperature for 10-15 hours, a 3-5 cm portion at the tip of the fresh corn cobs is removed to obtain fresh corn cobs after harvest.

3. The method for fermenting fresh corn according to claim 1, characterized in that: The S2: processing of harvested fresh corn cobs to obtain fresh corn crumbs, wherein the specific operation is to steam the harvested fresh corn cobs obtained in S1 with 100°C steam for 10-15 minutes, take them out, spread them out in a clean and ventilated place to cool to room temperature, thresh them to obtain fresh corn kernels, place the fresh corn kernels in a wall breaking machine, operate it at a medium or low gear for 8-15 seconds to obtain broken fresh corn kernels, place the broken fresh corn kernels in a clean blast drying oven at 45-55°C and dry them until the water content of the broken fresh corn kernels is 35-40%, thereby obtaining the fresh corn crumbs.

4. The method for fermenting fresh corn according to claim 1, characterized in that: The fresh corn culture medium comprises fresh corn shreds, carrot shreds, terrestrial Issatchen yeast wet bacterial mud, riboflavin and nicotinamide. The specific preparation method is: weigh 60-80 mg of riboflavin and 30-50 mg of nicotinamide, add them to 30-70 g of terrestrial Issatchen yeast wet bacterial mud, and stir them evenly; add 150-200 g of carrot shreds thereto, stir them evenly again; then add them to 1000-1500 g of the fresh corn shreds, stir them evenly, and package them, with 100-250 g in each 500 mL triangular bottle, and sterilize them at 115°C for 15 min.

5. The method for fermenting fresh corn according to claim 1 and claim 4, characterized in that: The preparation method of the carrot shreds comprises placing carrot pieces cut into 1-2 cm pieces in a wall breaking machine, operating the machine at a medium or low gear for 10-20 seconds, and then placing the pieces in a clean forced air drying oven at 45-55° C. and drying the pieces until the water content is 35-40%, thereby obtaining the carrot shreds.

6. The method for fermenting fresh corn according to claim 1, characterized in that: In step S4, the composition of the Ganoderma lucidum solid plate culture medium used to obtain Ganoderma lucidum fermented seeds is 8-15 g of Issatchengensis wet bacterial mud, 15-25 g of glucose, 150-200 g of potato, 0.1-0.4 g of MgSO4, and 20-25 g of agar per liter.

7. The method for fermenting fresh corn according to claim 1, characterized in that: The fermented ganoderma seeds obtained in step S4 are inoculated into the fresh corn culture medium obtained in step S3 under sterile conditions, stirred evenly with a sterile glass rod, and then cultured in an incubator at 22-28° C. for 6-12 days to obtain the fermented fresh corn; the inoculation amount of the fermented ganoderma seeds is 3-6 pieces of the fermented ganoderma seeds of 1.5-2 cm × 1.5-2 cm in size cut into each bottle of the fresh corn culture medium.

8. The method for fermenting fresh corn and its application in product processing according to claim 1, characterized in that: The fermented fresh corn is dried and crushed to obtain fermented fresh corn flour, which is used in product processing; the fermented fresh corn is freeze-dried or dried at 45-55°C and crushed to obtain the fermented fresh corn flour.

9. The use according to claim 1 and claim 8, characterized in that The fermented fresh corn flour is used in product processing.

10. The use according to claim 1 and claims 8 and 9, characterized in that The fermented fresh corn flour is directly processed into products, or applied to corn products, or in the processing of related products, or used to extract Ganoderma lucidum active substances.

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