Method for improving nutritional quality of wheat and reducing vomitoxin by combining cold plasma with lactobacillus fermentation

Abstract

The invention discloses a method for improving the nutritional quality of wheat and reducing vomitoxin by combining cold plasma with lactic acid bacteria fermentation. The method comprises the following specific steps: (1) putting wheat grains polluted by DON into a reaction cavity of cold plasma equipment; (2) preparing a single or compound lactic acid bacteria starter; (3) mixing the wheat subjected to cold plasma treatment with a lactic acid bacteria leavening agent for fermentation; and (4) drying, grinding and sieving the fermented wheat to prepare the wheat flour meeting the standard. Through progressive cooperative treatment of cold plasma pretreatment and compound lactobacillus fermentation, the final degradation rate of DON reaches 91.04%, functional components (resistant starch reaches 13.71% and dietary fiber reaches 13.14%) are synchronously increased, and phytic acid (lowest to 0.42%) is greatly degraded to improve the bioavailability of mineral substances. Besides, the method can optimize the wheat processing performance, the prepared noodles are moderate in hardness, good in elasticity and stretch-proof, no chemical reagent is added in the whole process, collaborative optimization of efficient detoxification, nutrient enrichment and processing performance improvement is achieved, and a green and economical solution is provided for safe utilization of polluted wheat.

Description

Technical Field

[0001] The present invention relates to the fields of agricultural product processing and food safety, and in particular to a method for improving the nutritional quality of wheat and reducing vomitoxin by utilizing cold plasma combined with lactic acid bacteria fermentation. Background Art

[0002] As one of the most widely cultivated and consumed grain crops in my country, wheat products (such as flour, noodles, and steamed buns) are a core component of the daily diet and play an irreplaceable role in ensuring food security and dietary nutrition. However, naturally occurring anti-nutritional factors and exogenous contaminants in wheat grains during growth, storage, and processing severely restrict their nutritional quality and food safety. Specifically, from the perspective of anti-nutritional factors, phytic acid is the most abundant phosphate compound in wheat, primarily concentrated in the aleurone layer and germ. The phosphate group has a strong chelating ability, binding to dietary minerals such as calcium, iron, zinc, and magnesium to form stable insoluble complexes, significantly reducing the solubility and bioavailability of these minerals in the human intestine. Furthermore, phytic acid can inhibit the activity of digestive enzymes such as amylase and protease, interfering with the digestion and absorption of carbohydrates and proteins, further weakening the nutritional value of wheat. Regarding food safety risks, deoxynivalenol (DON) is the primary mycotoxin produced by Fusarium contamination of wheat, with a contamination rate of over 60% in wheat and its products worldwide. DON has strong cytotoxic and immunosuppressive effects. Its toxic mechanism mainly inhibits protein synthesis by destroying ribosome function, thereby causing gastrointestinal reactions (such as nausea, vomiting, and diarrhea), neurotoxicity (such as headache and dizziness), and reproductive and developmental toxicity. At the same time, the content of resistant starch (RS) in wheat is generally low, which limits its functional value. How to increase the RS content in wheat has become an important direction for developing functional wheat products and expanding its nutritional added value. Therefore, how to simultaneously solve the problems of phytic acid anti-nutritional effects, DON toxin contamination, and low RS content in wheat is a technical bottleneck that urgently needs to be broken through in the current wheat processing field.

[0003] At present, the technical means to improve the quality and safety of wheat have covered multiple fields such as physics, chemistry, biology and composite synergy, but the existing methods generally have obvious limitations, making it difficult to achieve the synergistic optimization of "reducing anti-nutritional factors, removing toxins, and improving functional components". Specifically, although physical techniques (such as extrusion and irradiation) can improve some qualities through mechanical or energy effects, they have limited degradation of anti-nutritional factors such as phytic acid and are easy to destroy heat-sensitive nutrients. For example, patent CN 119073516 A discloses a method for preparing low-anti-nutritional factor soy milk using ultrasonic technology, which removes anti-nutritional factors from soy milk through soaking, refining, ultrasonication, high-pressure homogenization, heating and other steps. Patent CN 110907241 A discloses a method for plasma degradation of deoxynivalenol in an aqueous solution. A DON aqueous solution with an initial concentration of 5000 μg / L was selected and treated at 35 kV for 120 minutes. The content was reduced to below 300 μg / L. After the DON aqueous solution with an initial concentration of 1000 μg / L was treated under the same conditions, the content was reduced to 0. Although plasma technology is effective in degrading DON in aqueous solution, its core is to target "DON in aqueous solution." DON in grains is mostly found inside wheat grains (such as the endosperm and cortex) or combined with proteins and starch to form "bound DON." Plasma has difficulty penetrating the solid matrix to reach the toxin site, resulting in the actual degradation rate of wheat grains being much lower than that of aqueous solution. The strong oxidizing effect of excessive plasma can cause the molecular chains of macromolecules such as starch and protein to break (such as an imbalance in the straight chain / branched chain ratio of starch), reduce crystallinity, and cause the material to lose its original functionality (such as the gelling and water retention of starch). Excessive oxidation destroys heat-sensitive components such as vitamins (vitamin E, B group), polyphenols (ferulic acid, chlorogenic acid), etc., leading to nutrient loss. Patent CN 106721933 A discloses a method for degrading deoxynivalenol. Crops are laid flat on the assembly line of an electron accelerator irradiation device with an irradiation dose of 2-20 kGy. The maximum degradation rate of wheat samples with an initial DON content of 1400 μg / kg under irradiation conditions reached 56.7%. Solutions with initial concentrations of 1000 μg / L and 5000 μg / L were irradiated by electron accelerator, and the maximum degradation rates reached 83.4% and 55.2%, respectively. The maximum degradation rate of solid wheat grains by irradiation technology is much lower than that of aqueous solution systems, indicating that the complex matrix of wheat (such as cellulose and protein) will shield the irradiation energy, reducing the effect on internal DON. High-dose irradiation may cause DON to convert into more stable isomers, increasing the difficulty of subsequent detection and degradation. In addition, high irradiation doses can cause the starch molecular chains in wheat to break and gluten proteins to denature, increasing the gelatinization temperature of wheat flour and reducing water holding capacity, making it impossible to meet the processing requirements of flour products such as steamed buns and noodles.

[0004] Although chemical technologies (such as reagent detoxification) can quickly remove toxins, they may introduce chemical residues, leading to secondary pollution, and have little effect on improving functional ingredients (such as resistant starch). For example, patent CN 114617219B discloses a method for efficiently eliminating deoxynivalenol in wheat grains infected with ergot. The wheat grains are winnowed, sieved, de-stoned, carefully selected, and tempered. During the tempering step, chlorine dioxide solution is added in different proportions. The conventional tempering procedure is integrated to eliminate deoxynivalenol, so that the reduction of DON is greater than 75%. Although the use of chlorine dioxide solution to eliminate DON can achieve a certain detoxification effect, the residual chemical reagents may change the flavor of wheat (such as aldehydes and esters), and the excessive residual chlorine compounds may react with amino acids in wheat to form chlorinated derivatives (such as chloropropanols), increasing food safety risks. In addition, the use of chemical reagents requires strict control of dosage and residual standards, and the subsequent cleaning step may also lead to waste of water resources, which is contrary to the concept of "green processing". High concentrations of chlorine dioxide will destroy the disulfide bonds of wheat gluten protein, resulting in a decrease in the gluten index, affecting the subsequent extensibility and air retention of the dough, and thus reducing the quality of products such as bread and noodles; in addition, oxidation may cause the degradation of B vitamins (such as B1 and B6) in wheat, with a loss rate of 15%-30%.

[0005] Although biotechnology (such as single strain fermentation) can directionally degrade phytic acid or some toxins, its action efficiency is limited by microbial metabolic capacity and is less efficient. For example, patent CN 119769668 A discloses a method and application of probiotic fermentation degradation of rapeseed meal anti-nutritional factors, wherein aspergillus niger, yeast saccharomyces cerevisiae, bacillus velezii, and lactobacillus paracasei are cultured to obtain fermented seed liquid and inoculated into rapeseed meal, and aerobic solid-state fermentation is carried out, which can degrade the anti-nutritional factors in rapeseed meal and hydrolyze cell wall polysaccharides and crude protein, etc. simultaneously. Patent CN 120098855 A discloses a method and application of plant lactobacillus and its method for improving the content of resistant starch in chestnut powder by fermentation, wherein digestible starch in chestnut powder is preferentially enzymolyzed by controlling the fermentation time, thereby improving the content of resistant starch in chestnut powder, and the resistant starch content in unfermented chestnut powder is 30.53%, reaching a peak value of 37.82% by fermentation 36h, which has improved by 7.29%. Excessive fermentation will cause the pH of the system to be too low (too acidic), resulting in flavor deterioration, and may breed putrefactive bacteria or toxic microorganisms (such as certain molds), producing harmful substances such as aflatoxins and biogenic amines. Excessive fermentation can also cause excessive enzyme production by microorganisms, leading to excessive decomposition of starch into oligosaccharides, causing the system to become thinner and lose viscosity.

[0006] Even some combined technologies have failed to overcome the bottleneck of "giving priority to one thing and losing another" due to mismatched treatment mechanisms and poor parameter coordination, making it difficult to achieve both high degradation rates and quality preservation. For example, chemical methods are highly effective but leave residues, while physical methods are safe but inefficient. Their effectiveness in treating bound DON and deep-seated contaminants within wheat grains is limited, making it difficult to achieve the multi-faceted goals of reducing anti-nutritional factors, removing toxins, and enhancing functional ingredients. Summary of the Invention

[0007] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a method for improving the nutritional quality of wheat and reducing vomitoxin by using cold plasma combined with lactic acid bacteria fermentation. This method can enhance phytic acid degradation, increase the resistant starch content and significantly reduce the DON content, thereby achieving synergistic synergy in optimizing the nutritional quality of wheat and controlling safety risks. It is green, environmentally friendly and low-cost.

[0008] To achieve the above object, the present invention adopts the following technical solutions:

[0009] (1) Select wheat contaminated with DON and place it in the reaction chamber of a cold plasma device. The device uses dielectric barrier discharge and helium as the working gas. The active particles generated by the cold plasma can destroy the DON structure on the wheat surface and form tiny pores on the surface of the wheat grains, which is conducive to the subsequent penetration of lactic acid bacteria starter.

[0010] (2) Select lactic acid bacteria as the fermentation strain. Inoculate the strain into MRS liquid medium and culture at a constant temperature to obtain a seed culture solution. Then, inoculate the seed culture solution into fresh MRS liquid medium, continue to culture, and then centrifuge to collect the bacteria. Wash with sterile water and resuspend to prepare a lactic acid bacteria starter;

[0011] (3) The wheat treated with cold plasma is mixed with the lactic acid bacteria starter at a mass ratio of 7:1-14:1, and an appropriate amount of sterile water is added to control the moisture content of the wheat. The wheat is fermented and stirred regularly to ensure uniform fermentation.

[0012] (4) After fermentation, the wheat is dried in an oven to a moisture content of 12%-14%, and then subjected to conventional processing steps such as grinding and screening to produce wheat flour that meets food safety standards.

[0013] Furthermore, in step (1), the reaction chamber conditions of the cold plasma equipment are as follows: a helium flow rate of 10-20 L / min, a discharge voltage of 10-15 kV, and a treatment time of 5-15 min;

[0014] Furthermore, the lactic acid bacteria in step (2) are a single strain or a combination of multiple strains, including but not limited to lactic acid bacteria that produce organic acids or bacteriocins, such as Lactobacillus plantarum, Lactobacillus acidophilus and Lactobacillus rhamnosus;

[0015] Furthermore, in step (2), the bacteria were cultured at a constant temperature of 35-37°C for 18-24 hours to obtain a seed culture solution. The seed culture solution was inoculated with a 3%-5% inoculum into a fresh MRS liquid medium, and the culture was continued for 12-16 hours. The bacteria were collected by centrifugation, washed with sterile water, and resuspended. The concentration of the bacterial suspension was adjusted to 10 8 -10 9 CFU / mL, to prepare lactic acid bacteria starter culture; the centrifugation temperature is 25-40°C, the speed is 3000-5000r / min, and the time is 15-25min.

[0016] Furthermore, in step (3), the moisture content of the wheat is adjusted to 25%-30%, and the fermentation conditions are 30-35° C. and 12-48 hours.

[0017] Furthermore, in step (4), the wheat is placed in an oven at 40-50°C for drying.

[0018] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0019] (1) Synergistic and efficient detoxification, breaking through technical bottlenecks: Through the synergistic mechanism of "cold plasma pretreatment + compound lactic acid bacteria fermentation", the degradation rate of vomitoxin (DON) exceeds 90%, and the initial DON content of 2000μg / kg can be reduced to less than 200μg / kg, which is much higher than the effect of single lactic acid bacteria fermentation or single cold plasma treatment. The core of this method is the plasma etching of the wheat grain structure to release hidden toxins, activate bacterial metabolism, and the progressive degradation effect of the compound bacterial multi-enzyme system, breaking through the degradation limitations of traditional single methods.

[0020] (2) Adapt to complex matrices and achieve comprehensive degradation: It can efficiently process matrices of different forms such as wheat grains and flour, and especially solve the problem of incomplete degradation of toxins in complex matrices such as wheat grains with husk.

[0021] (3) Comprehensively improve quality and ensure nutrition and taste: While effectively reducing toxicity, it can significantly increase the functional components of wheat (dietary fiber reaches 13.14% and resistant starch reaches 13.71% after 10 minutes of processing), significantly degrade the anti-nutritional factor phytic acid (to a minimum of 0.42%), and improve the bioavailability of minerals; at the same time, it optimizes the processing characteristics of wheat flour, and the noodles produced have moderate hardness, good elasticity, and stretch resistance, achieving a dual improvement of "nutritional enhancement + texture improvement". Mild processing conditions avoid nutrient loss caused by high temperature or chemical methods, and the quality is better than single processing or traditional fermentation schemes.

[0022] (4) Green, environmentally friendly and residue-free, in line with safety requirements: No harmful chemical reagents are used throughout the process, cold plasma takes effect through physical oxidation, and compound lactic acid bacteria are used as a means of biological transformation. Both have no secondary pollution, and there is no chemical residue after treatment, which meets the green production and safety standards of the modern food industry.

[0023] (5) Low cost and easy to scale up, suitable for industrial production: cold plasma equipment is easy to operate and has low energy consumption (optimal processing time is 8-12 minutes, and unit energy consumption is reduced). The preparation cost of compound lactic acid bacteria starter is low and the raw materials are easy to obtain; the process is adapted to the rhythm of continuous production lines, which can reduce batch differences and equipment maintenance costs, and significantly lower the economic threshold for large-scale application. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Comparison of DON content and DON degradation rate in wheat of different treatment groups. DETAILED DESCRIPTION

[0025] The present invention will be further described in detail below with reference to the examples, but the embodiments of the present invention are not limited thereto.

[0026] Example 1 (compound lactic acid bacteria fermentation + cold plasma treatment)

[0027] Take 100g of wheat contaminated with DON, with an initial vomitoxin content of 2000μg / kg, and put it into the reaction chamber of the cold plasma equipment. The equipment uses dielectric barrier discharge, a helium flow rate of 20L / min, a discharge voltage of 15kV, and a treatment time of 10min. Lactobacillus plantarum, Lactobacillus acidophilus, and Lactobacillus rhamnosus are mixed in a ratio of 1:1:1, inoculated into MRS liquid culture medium, and cultured at a constant temperature of 35℃ for 18h to obtain seed culture solution. Inoculate fresh MRS liquid culture medium with a 5% inoculation amount, culture at 35℃ for 16h, collect the bacteria by centrifugation, wash with sterile water, and resuspend, and adjust the concentration of the bacterial suspension to 10 9 CFU / mL. Cold plasma-treated wheat was mixed with a lactic acid bacteria starter culture in a ratio of 10:1. Sterile water was added to bring the wheat moisture content to 30%. Fermentation was carried out at 32°C for 24 hours, with stirring every 6 hours. After fermentation, the wheat was oven-dried at 50°C to a moisture content of 14%, then ground and sieved to obtain wheat flour. Testing revealed that the DON content in the wheat flour was reduced to 179.23 μg / kg, meeting national standards.

[0028] Example 2 (lactic acid bacteria fermentation+cold plasma treatment)

[0029] Take 100g of wheat contaminated with DON, with an initial vomitoxin content of 2000μg / kg, and place it in the reaction chamber of the cold plasma equipment. The equipment uses dielectric barrier discharge, a helium flow rate of 20L / min, a discharge voltage of 15kV, and a treatment time of 10min. Inoculate Lactobacillus plantarum into MRS liquid culture medium and culture at a constant temperature of 35℃ for 18h to obtain seed culture solution. Inoculate fresh MRS liquid culture medium with a 5% inoculation amount, culture at 35℃ for 16h, collect the bacteria by centrifugation, wash with sterile water, and resuspend, and adjust the bacterial suspension concentration to 10 9 CFU / mL. Cold plasma-treated wheat was mixed with a lactic acid bacteria starter culture in a ratio of 10:1. Sterile water was added to bring the wheat moisture content to 30%. Fermentation was carried out at 30°C for 24 hours, with stirring every 6 hours. After fermentation, the wheat was oven-dried at 40°C to a moisture content of 14%, then ground and sieved to obtain wheat flour. Testing revealed that the DON content in the wheat flour was reduced to 512.05 μg / kg, meeting national standards.

[0030] Comparative Example 1 (traditional fermentation + cold plasma treatment)

[0031] 100g of DON-contaminated wheat, with an initial vomitoxin content of 2000μg / kg, was placed in the reaction chamber of a cold plasma device. The device used a dielectric barrier discharge (DBD) with a helium flow rate of 20L / min and a discharge voltage of 15kV for 10 minutes. The cold plasma-treated wheat was mixed with sterile water to a moisture content of 30% and fermented at 32°C for 24 hours, stirring every 6 hours. After fermentation, the wheat was dried in a 40°C oven to a moisture content of 14%, then ground and sieved to obtain wheat flour. Testing revealed that the DON content in the flour had dropped to 968.36μg / kg.

[0032] Comparative Example 2 (compound lactic acid bacteria fermentation)

[0033] Take 100g of wheat contaminated with DON, with an initial vomitoxin content of 2000μg / kg. Mix Lactobacillus plantarum, Lactobacillus acidophilus, and Lactobacillus rhamnosus in a 1:1:1 ratio, inoculate into MRS liquid medium, and incubate at 35℃ for 18h to obtain seed culture. Inoculate 5% of the inoculum into fresh MRS liquid medium, incubate at 35℃ for 16h, collect the cells by centrifugation, wash with sterile water, and resuspend. Adjust the concentration of the bacterial suspension to 10 9 CFU / mL. DON-contaminated wheat was mixed with a lactic acid bacteria starter culture at a ratio of 10:1. Sterile water was added to bring the wheat moisture content to 30%. The wheat was fermented at 32°C for 24 hours, stirring every 6 hours. After fermentation, the wheat was oven-dried at 50°C to a moisture content of 14%, then ground and sieved to obtain wheat flour. Testing revealed that the DON content in the wheat flour was reduced to 780.84 μg / kg.

[0034] Comparative Example 3-1 (compound lactic acid bacteria fermentation + cold plasma treatment)

[0035] The only difference between Comparative Example 3-1 and Example 1 is that the cold plasma treatment time is 5 minutes, and the other steps are the same as those in Example 1.

[0036] Comparative Example 3-2 (compound lactic acid bacteria fermentation + cold plasma treatment)

[0037] The only difference between Comparative Example 3-2 and Example 1 is that the cold plasma treatment time is 7 minutes, and the other steps are the same as those in Example 1.

[0038] Comparative Example 3-3 (compound lactic acid bacteria fermentation + cold plasma treatment)

[0039] The only difference between Comparative Example 3-3 and Example 1 is that the cold plasma treatment time is 13 minutes, and the other steps are the same as those in Example 1.

[0040] Comparative Example 3-4 (compound lactic acid bacteria fermentation + cold plasma treatment)

[0041] The only difference between Comparative Example 3-4 and Example 1 is that the cold plasma treatment time is 15 minutes, and the other steps are the same as those in Example 1.

[0042] Table 1 Chemical component content of wheat flour with different treatment methods

[0043]

[0044] Table 2 Texture parameters of noodles prepared from wheat flour with different treatment methods

[0045]

[0046] The comparison of DON content and DON degradation rate of wheat flour prepared according to the steps of Examples 1, 2 and Comparative Examples 1, 2 and 3 is shown in FIG. Figure 1 ; The changes in the chemical component content of wheat flour treated in different ways are shown in Table 1, and the texture parameters of noodles prepared from wheat flour treated in different ways are shown in Table 2.

[0047] The main conclusions are as follows:

[0048] (1) Example 1 (composite lactic acid bacteria + cold plasma) has the lowest DON content and the highest degradation rate (up to 91%). The core lies in the progressive synergistic mechanism of cold plasma pretreatment and composite lactic acid bacteria fermentation. Its advantage comes from the precise coupling of the metabolic complementarity of the composite bacteria and the physical effect of plasma, and is significantly better than single lactic acid bacteria (Example 2) and composite fermentation alone (Comparative Example 2). The reasons are speculated as follows: the active particles generated by cold plasma pretreatment first directly degrade part of the free DON through physical oxidation, while etching the dense structure of the wheat grain cell wall, destroying the cellulose-hemicellulose network, and releasing the hidden DON originally bound to protein and starch into a free state, providing sufficient substrate for lactic acid bacteria; in addition, the ultraviolet light and oxidation signals generated by the plasma can pre-activate the stress metabolic pathway of the composite lactic acid bacteria - such as inducing Lactobacillus plantarum to upregulate the expression of the de-epoxygenase gene, prompting Lactobacillus acidophilus to synthesize esterase precursors in advance, and reserve enzyme systems for subsequent efficient degradation. In the subsequent fermentation stage, the complex bacteria leverage the complementary metabolic pathways to fully exploit the favorable conditions created by pretreatment: the de-epoxidase secreted by Lactobacillus plantarum specifically destroys the epoxy group of DON, converting it to the less toxic 3-epi-DON; the esterase of Lactobacillus acidophilus decomposes the side chain acetyl group, reducing its cell-binding ability; and the glycosidase secreted by Lactobacillus rhamnosus further hydrolyzes the glycosidic bond of 3-epi-DON, converting it into a non-toxic small molecule carboxylic acid. These three enzyme systems synergistically degrade DON. This "pretreatment activation + fermentation synergy" sequence allows the complex bacteria to form a precise fit with the cold plasma, ultimately achieving a high degradation rate of 91%. A single bacteria, unable to cover the entire degradation pathway and having weak adaptability to the pretreatment microenvironment, struggles to achieve the same effect.

[0049] (2) The core of the "first increase and then decrease" of DON degradation efficiency in Example 1 and Comparative Example 3 lies in the dynamic balance between the cold plasma treatment intensity and the synergistic effect of the composite lactic acid bacteria: in the early stage (5-10 min), moderate plasma treatment etches the wheat grain cell wall through active particles, releasing the bound DON into a free state, and at the same time activating the degradative enzyme system of the composite bacteria, such as de-epoxidase and esterase. The composite bacteria, relying on the mechanism of "multi-enzyme synergistic degradation (destroying the toxic structure of DON) + cell wall adsorption (capturing free toxins)", works efficiently in a suitable microenvironment, with sufficient substrate and high enzyme activity, pushing the degradation rate to a rapid increase to 91.04%; in the later stage (10-15 min), excessive plasma treatment leads to excessive accumulation of active particles, inhibiting the activity of the composite bacteria and destroying the enzyme structure. At the same time, excessive etching of the cell wall releases inhibitory components, coupled with substrate (DON) depletion and microenvironment imbalance (increased redox potential), the metabolism of the composite bacteria turns to anti-oxidative stress, and the degradation efficiency drops accordingly. About 10 min becomes the optimal balance point of synergistic effect.

[0050] (3) While reducing the DON content in wheat, the effects of different treatment methods on the nutritional components of wheat differed significantly. Among them, Example 1 had the best effect. As the treatment time increased (5-15 min), the starch content continued to decrease, the protein content first increased and then stabilized, the dietary fiber and resistant starch content first increased and then slightly decreased (reaching peak values ​​of 13.14% and 13.71% respectively at 10 min), and phytic acid continued to degrade significantly (to a minimum of 0.42%), improving the bioavailability of minerals. Example 2 performed second best in all indicators, while Comparative Examples 1 and 2 had poor effects, especially the degradation of resistant starch and phytic acid was far less than that of Example 1. This shows that the synergistic effect of composite lactic acid bacteria and cold plasma (10 minutes of treatment is optimal) can maximize the improvement of wheat functional components (resistant starch, dietary fiber) and reduce anti-nutritional factors (phytic acid), and is significantly better than single lactic acid bacteria, traditional fermentation and plasma-free treatment schemes. It is speculated that this may be because cold plasma first etches the wheat cell wall through active particles to increase permeability, releasing substrates such as starch granules and dietary fiber precursors, while inducing starch molecular rearrangement to provide a structural basis for the formation of resistant starch and activate endogenous phytase precursors; subsequently, the composite lactic acid bacteria, relying on metabolic complementarity, secrete a complex enzyme system such as amylase, cellulase and phytase, and efficiently utilize the substrate exposed by pretreatment - amylase to promote the conversion of starch into resistant starch, cellulase degrades cell wall polysaccharides to increase dietary fiber, and phytase completely degrades free phytic acid, and the organic acids produced by fermentation further stabilize the structure of functional components. 10 minutes of plasma treatment can strike a perfect balance between "structural destruction" and "microenvironmental protection", fully releasing substrates and activating the enzyme system while avoiding starch oxidation or bacterial activity inhibition caused by excessive treatment. Single lactic acid bacteria, traditional fermentation or plasma-free treatment cannot achieve this effect due to limitations such as a single enzyme system and insufficient substrate release, ultimately achieving the synergistic optimization of maximizing functional ingredients and minimizing anti-nutritional factors.

[0051] (4) Comprehensive analysis shows that different treatment methods have a significant impact on the texture of wheat flour noodles: the noodles in the untreated group have high hardness, low elasticity, and high chewiness, and the tensile force and stretching distance are the worst, with obvious texture defects; while Example 1 performs best, with the lowest hardness and chewiness, and the highest elasticity, tensile force and stretching distance, achieving a high-quality taste with moderate hardness, good elasticity, easy chewing, and stretch resistance. Comparison shows that the advantage of Example 1 comes from the synergistic effect of the composite lactic acid bacteria and the 10-minute cold plasma. The composite bacteria optimize the gluten network through metabolic complementarity, and the plasma pretreatment balances cell wall destruction and structural protection. It is significantly better than single lactic acid bacteria (Example 2), traditional fermentation (Comparative Example 1), composite fermentation only (Comparative Example 2), and other plasma time treatments (Comparative Example 3 series), confirming that this combination is the optimal solution for improving noodle texture.

[0052] (5) In industrial production, locking the cold plasma treatment time at 8-12 minutes is the optimal choice that takes into account efficiency, cost and stability. This range covers both the high-efficiency degradation stage (DON degradation rate increases rapidly within 8-10 minutes) and avoids insufficient degradation of treatments below 8 minutes and excessive energy consumption of treatments exceeding 12 minutes. At the same time, this duration can form a synergistic relationship with the compound lactic acid bacteria and the fine-tuning of fermentation parameters to enhance enzyme activity and accumulation of functional ingredients, reduce batch differences, and adapt to the rhythm of continuous production lines. Ultimately, while ensuring a degradation rate of ≥90%, it reduces unit energy consumption and achieves the dual goals of cost reduction, efficiency improvement and quality stability.

[0053] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A method for improving the nutritional quality of wheat and reducing vomitoxin by using cold plasma combined with lactic acid bacteria fermentation, characterized in that: The following steps are involved: (1) Select wheat contaminated with DON and place it in the reaction chamber of a cold plasma device. The device uses dielectric barrier discharge, helium as the working gas, a helium flow rate of 10-20 L / min, a discharge voltage of 10-15 kV, and a treatment time of 5-15 min. (2) Select lactic acid bacteria as the fermentation strain, inoculate the strain into MRS liquid culture medium and culture at a constant temperature of 35-37°C for 18-24 hours to obtain seed culture solution; Then, the seed culture solution was inoculated into fresh MRS liquid medium at a 3% to 5% inoculum volume, and culture was continued for 12 to 16 hours. The bacteria were collected by centrifugation, washed with sterile water, and resuspended. The concentration of the bacterial suspension was adjusted to 10 8 - 10 9 CFU / mL, made into lactic acid bacteria starter culture; (3) The wheat treated with cold plasma is mixed with the lactic acid bacteria starter at a mass ratio of 7:1-14:1, and an appropriate amount of sterile water is added to control the moisture content of the wheat to 25%-30%. The fermentation is carried out at 30-35°C for 12-48 hours, and the mixture is stirred regularly during the fermentation to ensure uniform fermentation. (4) After fermentation, the wheat is placed in an oven and dried to a moisture content of 12% - 14%. It is then ground, sifted, and processed to produce wheat flour that meets food safety standards.

2. The method for improving the nutritional quality and detoxification of wheat by utilizing cold plasma combined with lactic acid bacteria fermentation according to claim 1, characterized in that: The treatment time of the cold plasma equipment reaction chamber in step (1) is 5-15 minutes.

3. The method for improving the nutritional quality and detoxifying wheat by utilizing cold plasma combined with lactic acid bacteria fermentation according to claim 1, characterized in that: In the step (2), the lactic acid bacteria are one or more of Lactobacillus plantarum, Lactobacillus acidophilus and Lactobacillus rhamnosus.

4. The method for improving the nutritional quality and detoxifying wheat by utilizing cold plasma combined with lactic acid bacteria fermentation according to claim 1, characterized in that: In step (2), the centrifugation temperature is 25-40°C, the rotation speed is 3000-5000 r / min, and the time is 15-25 min.

5. The method for improving the nutritional quality and detoxifying wheat by utilizing cold plasma combined with lactic acid bacteria fermentation according to claim 1, characterized in that: In step (4), the wheat is placed in an oven at 40-50°C for drying.

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