Method for improving the taste of millet porridge after long-term storage

Abstract

The application relates to a method for improving the eating taste of millet porridge after long-term storage, and belongs to the technical field of food storage, which solves the technical problem that millet is prone to poor eating taste after long-term storage and comprises the following steps: S1, preparing a natural antioxidant solution; S2, weighing millet raw materials; S3, uniformly spraying the natural antioxidant solution prepared in the step S1 on the millet raw materials weighed in the step S2, and continuously stirring the millet raw materials in the spraying process until the surface of the millet raw materials is wet; then, naturally air-drying the millet raw materials after the natural antioxidant solution is sprayed, and preparing high-phenol antioxidant millet; S4, placing the high-phenol antioxidant millet into a medicine stabilizing box for oxidation, and taking out the high-phenol antioxidant millet for long-term storage at-80 DEG C. The millet raw grain is combined with the antioxidant through a specific method, and the physical and chemical properties, eating quality and antioxidant property of the millet are greatly improved.

Description

Technical Field

[0001] This invention belongs to the field of food storage technology, specifically relating to a method for improving the taste of millet porridge after long-term storage. Background Technology

[0002] Millet is one of the earliest and most cultivated grain crops in my country, with a cultivation history of over 8,000 years. It has been listed among the "Five Grains" since ancient times, significantly influencing agricultural production and dietary structure in northern China and throughout the country. Rich in nutrients, it contains carbohydrates, dietary fiber, protein, minerals, and various bioactive components (such as phenols, flavonoids, and phytosterols). It not only provides basic energy for the human body but also plays a vital role in maintaining intestinal health, participating in growth and development, regulating immune function, and improving cardiovascular metabolism (such as assisting in blood sugar regulation and maintaining cardiovascular health).

[0003] The most common form of millet consumption is millet porridge, and its quality is directly related to the storage time of the raw materials. Studies have shown that as the storage time of millet raw materials increases, the taste and texture of millet porridge deteriorate significantly, mainly manifested in a coarser texture and decreased palatability. For example, Zhou Xianghan's research pointed out that after millet was stored at 40℃ for 10 weeks, the palatability and uniformity of the porridge changed significantly. Guo Jianwei also found that with the increase of storage time, the water absorption rate and expansion rate of millet porridge increased significantly, while the solid content and volume of the rice soup decreased, and the gelatinization viscosity, gelatinization temperature, and rheological parameters all showed an upward trend. These studies collectively indicate that the taste of porridge made from stored millet is significantly different from that made from fresh millet, which not only affects consumer acceptance but also leads to a significant reduction in its economic value. However, there are currently no effective measures to delay or mitigate the deterioration of the taste and texture of millet porridge after long-term storage. Summary of the Invention

[0004] To address the shortcomings of existing technologies and solve the technical problem that millet's taste deteriorates after long-term storage, this invention provides a method to improve the taste of millet porridge after long-term storage. Through a specific process, natural antioxidants are added to the millet raw material, thereby improving the taste of the porridge and significantly enhancing its quality.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: a method for improving the taste of millet porridge after long-term storage, comprising pretreatment of millet before long-term storage, including the following steps: S1. Weigh the natural antioxidants into a beaker, add distilled water or edible alcohol, stir thoroughly until dissolved, and prepare a natural antioxidant solution with a concentration of 0.05%~20% for later use; S2. Weigh the millet raw material into a beaker and set aside for later use; S3. Spray the natural antioxidant solution prepared in step S1 evenly onto the millet raw material weighed in step S2, and continuously stir the millet raw material during the spraying process until the surface of the millet raw material is wetted; then, let the millet raw material sprayed with the natural antioxidant solution air dry naturally to obtain high phenol antioxidant millet. S4. Place the high-phenol antioxidant millet prepared in step S3 into a drug stabilization chamber for storage. Set the temperature of the drug stabilization chamber to 50°C and the humidity to 55%. After storage, take out the high-phenol antioxidant millet to complete the storage.

[0006] This invention employs natural antioxidant regulation technology to significantly improve the quality stability of millet during long-term storage and enhance the palatability of porridge made from millet that has been stored for an extended period. The core mechanism of this invention lies in inhibiting lipid oxidation during millet storage by adding natural antioxidants, effectively delaying the accompanying starch oxidation, thereby intervening in and blocking the key degradation chain of "lipid oxidation-starch degradation," and improving the palatability of porridge made from millet that has been stored for a long time.

[0007] Furthermore, in step S1, the natural antioxidant is tea polyphenols, ferulic acid, or vitamin C.

[0008] The present invention, by adopting the above-described technical solution, has the following significant advantages compared to the prior art: (1) It is highly targeted and fills a current technological gap. Currently, there is a lack of economical and effective means to mitigate the quality deterioration of millet caused by lipid oxidation during storage. This invention slows down the decline in the storage quality of millet from the root by intervening in the core deterioration chain of "lipid oxidation-starch degradation", providing a feasible technical path for actual production; (2) Combining functionality and safety. The selected natural antioxidants not only have significant antioxidant activity and can effectively block oxidation chain reactions, but they are also derived from natural or plant extracts, which aligns with the clean label trend, ensures high safety, and is easily accepted by consumers; (3) Simple to operate and easy to promote. This invention does not rely on complex equipment or demanding processes. It can achieve the effect simply by adding an appropriate amount of natural antioxidants to the raw materials or processing steps. The process is simple, suitable for large-scale storage and processing, with low overall cost and good potential for industrial transformation. (4) Significant overall improvement effect. While extending the storage period, it can significantly maintain the overall palatability of millet porridge, so that millet stored for a long time can still maintain good edible quality and economic value, thus achieving a unified improvement in storage stability and edible quality. Attached Figure Description

[0009] Figure 1The pattern of fat oxidation during storage in millet treated with natural antioxidants; Figure 2 The effect of natural antioxidant treatment on the microstructure of millet grains in millet porridge made after storage; Figure 3 The changing pattern of starch content in millet treated with natural antioxidants during storage; Figure 4 The changes in starch molecular weight in millet treated with natural antioxidants during storage. Detailed Implementation

[0010] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0011] A method for improving the taste of millet porridge after long-term storage involves pre-treating the millet before long-term storage, including the following steps: S1. Weigh out the natural antioxidants tea polyphenols, ferulic acid and vitamin C into beakers to form three experimental groups. Add distilled water or edible alcohol to each group and stir thoroughly until dissolved to prepare a 2% natural antioxidant solution for later use. S2. Weigh the millet raw material into a beaker and set aside for later use; S3. Spray the natural antioxidant solution prepared in step S1 evenly onto the millet raw material weighed in step S2, and continuously stir the millet raw material during the spraying process until the surface of the millet raw material is wetted; then, let the millet raw material sprayed with the natural antioxidant solution air dry naturally to obtain high phenol antioxidant millet. S4. Place the high-phenol antioxidant millet prepared in step S3 into a drug stabilization chamber for oxidation. Set the temperature of the drug stabilization chamber to 50℃ and the humidity to 55%. After the high-phenol antioxidant millet has been stored, remove it to complete the storage process. Millet without added antioxidants and long-term stored millet sprayed with the chemically synthesized antioxidant TBHQ were used as control groups. The following is a comparative analysis of the raw material quality and porridge quality of the long-term stored millet (three experimental groups) and the control group (two groups) in this specific embodiment.

[0012] The method for making millet porridge using millet stored for different times in this embodiment includes the following steps: Weigh 1g of millet stored at -80℃ for different times, place it in a food-grade aluminum box (5cm in diameter and 3cm in height), and wash it three times with distilled water; then add 20mL of distilled water to the food-grade aluminum box, mix it evenly with the millet, and place it in a steamer to steam at 85℃ for 30 minutes to obtain millet porridge. Verification experiments were conducted on this technology, and the specific results are as follows.

[0013] (a) The effect of natural antioxidants on lipid oxidation during millet storage; Depend on Figure 1 It can be seen that, compared with the control group, the groups with added natural antioxidants maintained low levels of peroxide and malondialdehyde (MDA) at 30 and 60 days of storage, and their effects were comparable to those of the synthetic antioxidant TBHQ. This indicates that natural antioxidants can inhibit oxidation reactions during millet storage and significantly delay the accumulation of peroxide and MDA during storage.

[0014] (ii) The effect of natural antioxidants on the taste of millet porridge after storage; Table 1 compares the effects of natural antioxidant treatment on the improved taste of millet porridge after storage. As shown in Table 1, in the control group without added antioxidants, the water absorption of the millet grains initially increased and then decreased, the expansion rate continuously decreased, the volume of the rice water continuously increased, and the soluble solids content continuously decreased. In contrast, the addition of antioxidants significantly alleviated the deterioration of all indicators. Table 2 shows the textural characteristics of millet grains in porridge made after storage. It can be found that in the control group without added antioxidants, the hardness of the millet grains in porridge made after storage continuously increased, and the elasticity and chewiness continuously improved. In contrast, the millet treated with natural antioxidants showed significantly inhibited deterioration in key quality indicators such as texture and viscosity after storage. These results indicate that natural antioxidant treatment significantly improves the taste of millet porridge made after storage.

[0015] .

[0016] .

[0017] (III) Microstructure of millet grains in porridge made from stored millet The grains of millet porridge prepared from different samples were freeze-dried, and their microstructure was observed using scanning electron microscopy. The results showed that the microstructure of the grains in porridge made from fresh millet was dense, while the microstructure of the grains in porridge prepared after 60 days of storage gradually transformed into a looser, more porous structure (e.g., ...). Figure 2 (As shown). In contrast, after being treated with natural antioxidants and stored for 60 days, the microstructure of the millet grains in the porridge was closer to that of fresh millet, maintaining a relatively dense and intact microstructure to a certain extent, effectively mitigating the aforementioned structural deterioration. This indicates that natural antioxidant treatment can maintain the internal structure of millet after cooking, preventing it from evolving from "dense and few-pore" to "loose and porous".

[0018] (iv) The protective effect of natural antioxidants on starch during millet storage like Figure 3As shown, the starch content of millet samples without antioxidant treatment (control group) showed a significant decreasing trend during 60 days of accelerated storage: amylose content decreased from 23.31 g / 100g to 22.68 g / 100g, and amylopectin content decreased from 56.13 g / 100g to 35.88 g / 100g, with the degradation rate of amylopectin being significantly higher than that of amylose. In contrast, millet treated with antioxidants showed significantly higher amylose and amylopectin contents than the control group during 60 days of storage. Figure 4 The molecular weight distribution of millet starch in different samples is shown. Figure 3 It can be seen that the average molecular weight of amylopectin in fresh millet is 134211.9 kDa, which decreases to 118883.4 kDa after 60 days of storage. In contrast, treatment with natural antioxidants effectively curbed the decrease in the molecular weight of amylopectin and maintained the original characteristics of the starch molecular weight distribution. These results indicate that treatment with natural antioxidants has a good protective effect on starch.

[0019] Based on the above analysis, it can be inferred that during storage, the degradation of starch in millet mainly originates from the glycosidic bond breakage caused by reactive oxygen free radicals generated by lipid oxidation. After treatment with natural antioxidants, the oxidative stress on starch molecules can be reduced by scavenging lipid oxidation free radicals, thereby maintaining the integrity of the starch molecule structure and significantly improving the taste of porridge made from the raw materials after storage.

[0020] In summary, antioxidant pretreatment significantly reduced the content of peroxides and malondialdehyde (MDA) in millet during storage by 27.7% and 26.0%, respectively, and reduced amylopectin degradation by 30%-62.7%. This significantly improved key quality indicators in the porridge, such as water absorption rate, hardness, and soluble solids, effectively mitigating the decline in porridge quality caused by prolonged storage of millet. Using this technology, under the same storage conditions, the taste of the porridge made from millet is closer to that of fresh millet.

[0021] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for improving the taste of millet porridge after long-term storage, characterized in that, Pre-treatment of millet before long-term storage includes the following steps: S1. Weigh the natural antioxidants into a beaker, add distilled water or edible alcohol, stir thoroughly until dissolved, and prepare a natural antioxidant solution with a concentration of 0.05%~20% for later use; S2. Weigh the millet raw material into a beaker and set aside for later use; S3. Spray the natural antioxidant solution prepared in step S1 evenly onto the millet raw material weighed in step S2, and continuously stir the millet raw material during the spraying process until the surface of the millet raw material is wetted; then, let the millet raw material sprayed with the natural antioxidant solution air dry naturally to obtain high phenol antioxidant millet. S4. Place the high-phenol antioxidant millet prepared in step S3 into a drug stabilization chamber for storage. Set the temperature of the drug stabilization chamber to 50°C and the humidity to 55%. After storage, take out the high-phenol antioxidant millet to complete the storage.

2. The method for improving the taste of millet porridge after long-term storage, as described in claim 1, is characterized in that... In step S1, the natural antioxidant is tea polyphenols, ferulic acid, or vitamin C.

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