Ophiopogon japonicus rice vinegar and preparation method thereof

Abstract

The invention discloses orchid rice vinegar and a preparation method thereof, relates to the field of rice vinegar preparation, and provides orchid rice vinegar which is more perfect and balanced and is easy to standardize. Comprising the following technological processes: cleaning glutinous rice and orchid rice, removing impurities, soaking the rice, steaming the rice, cooling, adding distiller's yeast, fermenting, heating, cooling, adding acetic bacteria, fermenting, uniformly mixing the materials, stirring by a wall breaking machine, and heating to obtain the orchid rice vinegar base material finished product. The glutinous rice and the orchid rice are subjected to alcoholic fermentation, the yellow bell peppers and various seasonings are added, the orchid rice vinegar is prepared, all the advantages of the glutinous rice, the orchid rice, the yellow bell peppers and other raw materials are reserved, the taste is more delicious, and the utilization rate of various nutrients is increased. The processing technology conditions of the orchid rice vinegar are determined through single factor analysis and response surface tests, and the method aims at providing reference for the production technology of the orchid rice vinegar and providing a theoretical basis for research and development of products.

Description

Technical Field

[0001] The invention relates to the field of rice vinegar preparation, in particular to Shanlan rice vinegar and a preparation method thereof. Background Art

[0002] Disadvantages of existing Shanlan rice vinegar:

[0003] 1. Limited taste acceptance: Shanlan rice vinegar soup base is characterized by its unique sour and spicy taste, but this taste may not suit everyone's taste. Some people may not be very adaptable to this unique sour taste, thus limiting the audience range of Shanlan rice vinegar.

[0004] 2. Unbalanced nutritional ratio: Although Shanlan rice itself has certain nutritional value, when making vinegar, the balanced ratio with other nutrients may be ignored. Long-term consumption may lead to unbalanced nutritional intake and affect health.

[0005] 3. Standardization and stability issues: Since the production process of Shanlan rice vinegar may vary to a certain extent, products produced by different manufacturers may vary greatly in taste, quality, etc. This affects the standardization and stability of the product, which is not conducive to market promotion and consumer choice. Summary of the invention

[0006] In view of the above-mentioned problems, the present invention aims to provide a Shanlan rice vinegar and a preparation method thereof, and to provide a Shanlan rice vinegar that is more complete, balanced and easy to standardize.

[0007] The main ideas of the technical solution adopted by the present invention are:

[0008] 1. Improve the taste acceptance: The present invention optimizes the raw material ratio and production process to make it more in line with the public taste while maintaining the unique flavor of Shanlan rice. By adjusting the acidity and spiciness, the product is more acceptable, thereby expanding the audience range.

[0009] 2. Improve the nutritional ratio: The present invention focuses on the nutritional balance of Shanlan rice vinegar. By scientifically proportioning various raw materials, the physical and chemical indicators of Shanlan rice vinegar are determined, and the content of various nutrients such as protein, fat, carbohydrates, free fatty acids, etc. is determined to ensure that the product is rich in various nutrients. This helps to meet consumers' demand for healthy diet and improve the market competitiveness of the product.

[0010] 3. Achieve standardization and stability: The present invention ensures that different batches of products remain consistent in taste, quality, etc. by formulating strict production processes and quality control standards. This helps to improve the standardization and stability of products, and facilitates market promotion and consumer choice.

[0011] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0012] A kind of mountain blue rice vinegar, characterized by comprising the following raw material components:

[0013] Glutinous rice, mountain rice, wine yeast, acetic acid bacteria and seasoning;

[0014] The mass ratio of the glutinous rice, mountain rice, wine yeast, acetic acid bacteria and seasoning is 1750:750:25:1:1875.

[0015] Furthermore, the seasoning agent consists of monosodium glutamate, salt, white sugar, yellow bell pepper and red bell pepper, and the mass ratio of monosodium glutamate, salt, white sugar, yellow bell pepper and red bell pepper is 17:25:20:3:10.

[0016] The invention also discloses a method for preparing mountain rice vinegar, which is characterized by comprising the following steps:

[0017] Step 1: Mix glutinous rice and mountain rice in a mass ratio of 7:3 and wash them clean to obtain mixed rice for later use;

[0018] Step 2: adding water to the mixed rice in step 1 and soaking for 6 to 8 hours to obtain soaked rice;

[0019] Step 3: Add water to the soaked rice in step 2 and steam for 30 minutes to obtain steamed rice;

[0020] The mass ratio of the soaked rice to water is 2:1;

[0021] Step 4: Cool the steamed rice in step 3 to reduce the temperature of the steamed rice to 28-32° C. to obtain cooled rice;

[0022] Step 5: adding distiller's yeast and water to the cooled rice in step 4, fermenting to obtain distiller's grains, heating at 85° C. for 30 minutes, then cooling to room temperature, adding acetic acid bacteria, and obtaining rice to be fermented;

[0023] The mass ratio of the koji, water and glutinous rice is 1:10:70; and the mass ratio of the koji to acetic acid bacteria is 25:1;

[0024] Step 6: fermenting the rice to be fermented in step 5 to obtain fermented rice vinegar;

[0025] Step 7: adding the flavoring agent to the fermented rice vinegar in step 6, crushing and stirring to mix well, to obtain a preliminary product of Shanlan rice vinegar;

[0026] Step 8: Heat the preliminary Shanlan rice vinegar product in step 7 to 100° C., dissolve for 5 minutes, and stir evenly to obtain the finished Shanlan rice vinegar.

[0027] Furthermore, in step 2, the height of the water surface from the surface of the mixed rice is 10 cm.

[0028] Furthermore, in step 5, the fermentation temperature is 28° C. and the fermentation time is 72 hours.

[0029] Furthermore, in step 6, the fermentation temperature is 26-34° C., and the fermentation time is 70-170 hours.

[0030] Furthermore, the mass ratio of the seasoning to the mountain rice in step 7 is 5:2.

[0031] The beneficial effects of the present invention are as follows: compared with the prior art, the present invention has the following improvements:

[0032] Shanlan rice vinegar is prepared by adding yellow bell pepper and various seasonings to glutinous rice and Shanlan rice through alcohol fermentation. It not only retains all the advantages of glutinous rice, Shanlan rice, yellow bell pepper and other raw materials, but also tastes more delicious and improves the utilization rate of various nutrients. The processing conditions of Shanlan rice vinegar were determined by single factor analysis and response surface experiment, aiming to provide a reference for the production process of Shanlan rice vinegar and provide a theoretical basis for product research and development.

[0033] By optimizing the process formula of Shanlan rice vinegar and conducting sensory and quality research, the effects of adding various substances on the quality of Shanlan rice vinegar were analyzed. This will open up a new idea for the development and utilization of Shanlan rice vinegar resources, lay the foundation for the research and development of new condiments, and play a positive role in promoting the development of my country's condiment industry, providing technical support and theoretical basis. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is the contour point relationship diagram of the Shanlan rice vinegar fermentation time and fermentation temperature response surface.

[0035] Figure 2 This is the contour diagram of the response surface between Shanlan rice vinegar fermentation time and material-liquid ratio.

[0036] Figure 3 This is the iso-peak relationship diagram of the response surface between Shanlan rice vinegar fermentation time and material-liquid ratio.

[0037] Figure 4 This is the contour relationship diagram of the fermentation time and fermentation temperature response surface.

[0038] Figure 5 This is the relationship diagram of the response surface iso-peaks between fermentation time and material ratio.

[0039] Figure 6 This is the response surface contour diagram of fermentation time and material ratio.

[0040] Figure 7 It is the iso-peak relationship diagram of the fermentation temperature and the material-liquid ratio response surface.

[0041] Figure 8 Response surface contour plot of fermentation temperature and material ratio.

[0042] Fig. 9 It is the iso-high point relationship diagram of the response surface of the material-liquid ratio and the material ratio.

[0043] Fig.10 This is the contour diagram of the response surface between fermentation temperature and feed-liquid ratio.

[0044] Fig.11 It is the iso-high point relationship diagram of the response surface of the material-liquid ratio and the material ratio.

[0045] Fig.12 It is the contour relationship diagram of the response surface between the material-liquid ratio and the material ratio.

[0046] Fig.13 The variance analysis of each term of the regression equation.

[0047] Fig.14 This is a graph showing the effect of different alcohol fermentation times on the sensory quality of lees.

[0048] Fig.15 This is a graph showing the effects of different alcohol fermentation temperatures on the sensory quality of lees.

[0049] Fig.16 This is a graph showing the effect of different fermentation times on the sensory quality of Shanlan rice.

[0050] Fig.17 This is a graph showing the effect of different fermentation temperatures on the sensory quality of Shanlan rice.

[0051] Fig.18 This is a graph showing the effects of different material ratios on the sensory quality of Shanlan rice vinegar.

[0052] Fig.19 This is a graph showing the effect of different material-liquid ratios on the sensory quality of Shanlan rice vinegar.

[0053] Fig. 20 This is a graph showing the effects of different amounts of yellow bell pepper added on the sensory quality of Shanlan rice vinegar base.

[0054] Fig.21 This is a graph showing the effects of different amounts of red bell pepper added on the sensory quality of Shanlan rice vinegar base.

[0055] Fig. 22 This is a graph showing the effects of different amounts of added white sugar on the sensory quality of Shanlan rice vinegar base.

[0056] Fig.23 This is a graph showing the effects of different amounts of MSG on the sensory quality of Shanlan rice vinegar base.

[0057] Fig.24 This is a graph showing the effects of different amounts of salt added on the sensory quality of Shanlan rice vinegar base.

[0058] Fig.25 The contour lines and response surface diagrams of the interaction effects of various factors on sensory scores;

[0059] Among them, A is the sensory score change of Shanlan rice vinegar under different fermentation time and fermentation temperature combinations;

[0060] B is the sensory score changes of Shanlan rice vinegar under different fermentation time and material-liquid ratio combinations;

[0061] Fig.26 The contour lines and response surface diagrams of the interaction effects of various factors on sensory scores;

[0062] Among them, C is the sensory score change of Shanlan rice vinegar under different fermentation time and material ratio combinations;

[0063] D is the sensory score change of Shanlan rice vinegar under different fermentation temperatures and material-liquid ratio combinations;

[0064] Fig. 27 The contour lines and response surface diagrams of the interaction effects of various factors on sensory scores;

[0065] Among them, E is the sensory score change of Shanlan rice vinegar under different fermentation temperatures and material ratio combinations;

[0066] F is the change in sensory score under different combinations of material-liquid ratio and material ratio. DETAILED DESCRIPTION

[0067] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0068] Experimental materials: glutinous rice: produced in China; mountain rice: produced in China; yellow lantern pepper: produced in Hainan Province; red lantern pepper: produced in various provinces across the country; brewer's yeast: selected by the Musalais Quality Testing Center of Xinjiang Institute of Technology; white sugar, monosodium glutamate, and salt.

[0069] Table 1 Main instruments

[0070]

[0071] Table 2 Main reagents

[0072]

[0073] Test methods

[0074] Process

[0075] Glutinous rice, Shanlan rice → wash and remove impurities → soak rice → steam rice → let cool → add koji → ferment → heat → cool → add acetic acid bacteria → ferment → mix ingredients → stir with wall breaking machine → heat → Shanlan rice vinegar is finished.

[0076] The Shanlan rice vinegar obtained by the above process includes the following raw material components:

[0077] Glutinous rice, mountain rice, wine yeast, acetic acid bacteria and seasoning;

[0078] Among them, the mass ratio of glutinous rice, mountain rice, koji, acetic acid bacteria and seasoning is 1750:750:25:1:1875.

[0079] The seasoning consists of monosodium glutamate, salt, white sugar, yellow bell pepper and red bell pepper, and the mass ratio of monosodium glutamate, salt, white sugar, yellow bell pepper and red bell pepper is 17:25:20:3:10.

[0080] Specifically, the preparation method of mountain rice vinegar comprises the following steps:

[0081] Step 1: Mix glutinous rice and mountain rice in a mass ratio of 7:3 and wash them clean to obtain mixed rice for later use;

[0082] Step 2: adding water to the mixed rice in step 1 and soaking for 6 to 8 hours to obtain soaked rice; more specifically, the height of the water surface from the surface of the mixed rice is 10 cm;

[0083] Step 3: Add water to the soaked rice in step 2 and steam for 30 minutes to obtain steamed rice;

[0084] The mass ratio of soaked rice to water is 2:1;

[0085] Step 4: Cool the steamed rice in step 3 to reduce the temperature of the steamed rice to 28-32° C. to obtain cooled rice;

[0086] Step 5: adding distiller's yeast and water to the cooled rice in step 4, fermenting to obtain distiller's grains, heating at 85° C. for 30 minutes, then cooling to room temperature, adding acetic acid bacteria, and obtaining rice to be fermented;

[0087] More specifically, the fermentation temperature was 28°C and the fermentation time was 72 h;

[0088] The mass ratio of koji, water and glutinous rice is 1:10:70; and the mass ratio of koji and acetic acid bacteria is 25:1;

[0089] Step 6: fermenting the rice to be fermented in step 5 to obtain fermented rice vinegar;

[0090] More specifically, the fermentation temperature is 26-34°C and the fermentation time is 70-170h;

[0091] Step 7: adding the flavoring agent to the fermented rice vinegar in step 6, fully crushing and stirring to obtain a preliminary product of Shanlan rice vinegar; wherein the mass ratio of the flavoring agent to Shanlan rice is 5:2;

[0092] Step 8: Heat the preliminary Shanlan rice vinegar product in step 7 to 100° C., dissolve for 5 minutes, and stir evenly to obtain the finished Shanlan rice vinegar.

[0093] In the preparation process of Shanlan rice vinegar, the following points should also be noted:

[0094] The specific operation of cleaning in step 1 is: place the glutinous rice and mountain rice in a rice washing basket and wash them repeatedly until the water is not turbid, and select and remove impurities in the rice.

[0095] The specific operation of soaking in step 2 is as follows: wash the large beaker, put in the glutinous rice and mountain rice in proportion, remove impurities, put in clean water, wash the rice, and keep the water level 10cm higher than the upper layer of the rice. The purpose of soaking the rice is to gelatinize the starch during cooking and promote the catalytic action of microbial enzymes. The degree of soaking the rice is required to pinch the rice without hard core and become powdery.

[0096] The specific operation of steaming rice in step 3 is: put the soaked glutinous rice and mountain rice into the steamer, add water according to the normal proportion, and steam for 30 minutes until the rice aroma comes out. Standard: loose, soft, transparent, and non-sticky.

[0097] The specific operation of cooling in step 4 is: take out the cooked glutinous rice and mountain rice and place them in a cool and ventilated place to cool. The purpose is to let them dissipate heat and reduce their temperature to a range suitable for fermentation.

[0098] The specific operation of adding koji in step 5 is: put the cooled glutinous rice and mountain rice into the fermentation conical bottle, add a certain proportion of koji and water and mix well. The mass ratio of koji, water and glutinous rice is 1:10:70; and the mass ratio of koji to acetic acid bacteria is 25:1;

[0099] The specific operation of fermentation in step 6 is: placing the wine lees to be fermented in a constant temperature incubator for fermentation, the fermentation temperature is 28° C., and the fermentation time is 72 hours.

[0100] The specific operation of fully crushing and stirring in step 7 is: stirring and mixing in a wall-breaking machine to further form the preliminary product of Shanlan rice vinegar. The wall-breaking machine can retain the nutrients in the materials through high-speed stirring and grinding by its own weight, avoiding the harm of added MSG and salt to the body.

[0101] The specific operation of heating in step 8 is: take the preliminary product of Shanlan rice vinegar out of the wall breaking machine and pour it into a weighing bottle, then put it into a preheated pan, adjust the temperature to 100°C and heat for 5 minutes to dissolve the undissolved granular matter.

[0102] Response Surface Experimental Design

[0103] Based on single factor experiment and central composite design principle, a four-factor three-level optimization design was carried out for Shanlan rice vinegar process. In Shanlan rice vinegar, the coding of each variable factor and its level is shown in the following table 3.

[0104] Table 3 The factor level table

[0105]

[0106] Response surface experiment results and analysis

[0107] On the basis of the single factor experiment of acetic acid fermentation formula, the central combination design principle of Design-expert 13 software was adopted, and the fermentation time, fermentation temperature, material-liquid ratio and material ratio of Shanlan rice vinegar were selected as experimental factors. With sensory score as the response value, four factors and three levels were designed for a total of 29 experiments, and a mathematical model was established to obtain the optimal process conditions of Shanlan rice vinegar.

[0108] With the four factors of Shanlan rice vinegar fermentation time (A), Shanlan rice vinegar fermentation temperature (B), material-liquid ratio (C), and material ratio (D) as independent variables and the sensory score of Shanlan rice vinegar as the response value, a central composite experiment design was carried out and the results are shown in Table 4.

[0109] Table 4. Experimental design result

[0110]

[0111] Response surface plot analysis

[0112] The response surface analysis diagram based on the binary regression model was obtained by using Design-Expert 13 software. Figure 1-Figure 13 .

[0113] Figure 1 The figure shows the sensory score changes of Shanlan rice vinegar under different fermentation time and fermentation temperature combinations. As can be seen from the figure, with the increase of fermentation time, the sensory score gradually increases, but after more than 168h, the sensory score will decrease with the increase of fermentation time. The change of fermentation temperature has a significant effect on the sensory score, especially within a certain range, the change of temperature will cause significant fluctuations in the score.

[0114] Figure 2 In the figure, red and yellow are used to indicate areas with higher sensory scores, while green and blue are used to indicate areas with lower sensory scores. As the fermentation time of Shanlan rice vinegar increases, the sensory score gradually increases, but when the fermentation time exceeds a certain range, the sensory score begins to decrease. At the same time, the material-liquid ratio has a significant effect on the sensory score. In areas with a lower material-liquid ratio, the sensory score is generally higher; while in areas with a higher material-liquid ratio, the sensory score is relatively low.

[0115] Figure 3 The figure shows the iso-peak relationship diagram of the response surface of fermentation time and liquid-to-liquid ratio, while the color and height represent the sensory score values ​​of the two variables under different combinations. As the fermentation time increases, the influence of the change in liquid-to-liquid ratio on the score gradually decreases and eventually stabilizes. At the same time, when the fermentation time is short, the liquid-to-liquid ratio has a greater influence on the score; while when the fermentation time is long, this influence gradually weakens. And the sensory score value is the highest when the fermentation time = 0.50 and the liquid-to-liquid ratio = -0.50.

[0116] Figure 4 Different color areas are used to represent the range of different sensory score values, where yellow and red represent higher scores, while green and blue represent lower scores. This visualization method intuitively shows the correlation between fermentation time and fermentation temperature on sensory scores, which helps to understand how different parameters affect the sensory characteristics of the product.

[0117] Figure 5 The color change of the surface in the figure represents the sensory score value under different fermentation time and material ratio combinations, where red represents a higher score value and green represents a lower score value. The yellow area below the figure represents the distribution of sensory scores with fermentation time within a given material ratio range (-0.5 to 1.0).

[0118] Figure 6 The colors represent the range of sensory scores, with green representing lower scores and red representing higher scores. The figure shows that a specific combination of fermentation time and material ratio (approximately A=0.5 and D=0) can obtain the highest sensory score.

[0119] Figure 7 The sensory scores under different fermentation times and material-liquid ratios are shown in Figure 2. From the distribution, the sensory scores gradually decrease with the increase of fermentation temperature and material-liquid ratio. This may be related to the changes of certain substances during the fermentation process.

[0120] Figure 8 The relationship between fermentation temperature and material ratio on sensory scores is shown in Figure 1. Under a specific combination of material ratio and fermentation temperature, the sensory score may reach the highest value (such as 95 points), while under other combinations it may be lower (such as 75 points).

[0121] Fig. 9 As the material ratio increases, the sensory score gradually increases, but tends to stabilize when the material ratio is too high. This means that increasing the material ratio within a certain range can improve the sensory score, but the effect is not obvious beyond this range. As the material-liquid ratio increases, the sensory score also gradually increases, but tends to stabilize when the material-liquid ratio is too high. This shows that increasing the material-liquid ratio within a certain range can improve the sensory score, but the effect is not obvious beyond this range.

[0122] Fig.10 By observing the data points in the heat map, we can find some trends. As the fermentation temperature increases (from left to right), the sensory score seems to increase first and then decrease; while as the material-liquid ratio increases (from bottom to top), the sensory score shows an overall upward trend. These trends may reflect the mechanism by which certain parameters in the fermentation process affect the sensory quality.

[0123] Fig.11 It means that when the material ratio increases, the sensory score first increases and then decreases; while when the material-liquid ratio increases, the sensory score first increases and then decreases as a whole.

[0124] Fig.12 It shows that when the material ratio (D) is 0.0, the sensory score is the highest; when it is close to 1.0, as the material ratio increases, the sensory score begins to decrease; similarly, when the material-liquid ratio is close to 0.00, the sensory score value reaches the maximum value.

[0125] right Fig.13 The data were analyzed and the regression equation of sensory score was established: R1 = +89.78 + 3.48*A-2.87*B-1.45*C + 1.37*D + 0.95*AB-3.05*AC + 1.55*AD-3.08*BC + 3.15*BD + 0.22*CD-5.87*A^2-6.11*B^2-3.67*C^2-7.19*D^2

[0126] Depend on Figure 25-27It can be seen that the response surface gradient can better reflect the interaction between various factors, and the interaction between factors can reflect the influence of the sensory evaluation of Shanlan rice vinegar. It can be seen from the highest point and contour lines of the response surface that there is an extreme value within the selected range, which is not only the highest point of the response surface, but also the center point of the minimum ellipse of the contour line. The interaction of each factor is significant, which is significantly consistent with the data. According to the estimated values ​​of the equation coefficients, A (Shanlan rice vinegar fermentation time): 120h, B (Shanlan rice vinegar fermentation temperature): 30℃, C (material ratio): 3:7, D (material-liquid ratio): 2:1. Among them, A is the change in sensory score of Shanlan rice vinegar under different combinations of fermentation time and fermentation temperature; B is the change in sensory score of Shanlan rice vinegar under different combinations of fermentation time and material-liquid ratio;

[0127] C is the sensory score change of Shanlan rice vinegar under different fermentation time and material ratio combinations;

[0128] D is the sensory score change of Shanlan rice vinegar under different fermentation temperatures and material-liquid ratio combinations;

[0129] E is the sensory score change of Shanlan rice vinegar under different fermentation temperatures and material ratio combinations;

[0130] F is the change in sensory score under different combinations of material-liquid ratio and material ratio.

[0131] Single factor experimental design of fermentation recipe

[0132] Glutinous rice and mountain rice were used for fermentation. A single factor experiment was conducted with alcohol fermentation time (70h, 72h, 74h), alcohol fermentation temperature (27℃, 28℃, 29℃), lees vinegar fermentation time (96h, 120h, 144h), lees vinegar fermentation temperature (28℃, 30℃, 32℃), material-liquid ratio (1.5:1, 2:1, 2.5:1), material ratio (2:8, 3:7, 4:6) as influencing factors and sensory score as evaluation index.

[0133] It should be noted that the material-liquid ratio is the mass ratio of soaked rice and water; the material ratio is the mass ratio of mountain rice and glutinous rice.

[0134] Results and analysis of single factor test on fermentation formula

[0135] ① Effects of different alcohol fermentation times on the sensory quality of lees

[0136] like Fig.14As shown in the figure, the sensory quality of the lees increases first and then decreases with the extension of fermentation time, and reaches a peak at 72h. Because a lot of gas is generated during the fermentation of the lees, the glutinous rice and mountain rice become loose honeycombs, and the taste is relatively better. At this time, the sensory score is 88.60 points, and the measured alcohol content is 7.2%vol. After 72h, the sensory score shows a downward trend, which may be because the fermented wine has reached a more suitable fermentation point, and if the fermentation time is too long, the sourness and astringency of the wine will increase. The lowest alcohol content is 7.0%vol at 68h, which may be due to the short action time of the yeast in the lees, resulting in less alcohol and aroma substances, affecting the sensory quality.

[0137] ②Effects of different alcohol fermentation temperatures on the sensory quality of lees

[0138] from Fig.15 It can be seen that with the increase of fermentation temperature, the sensory quality score of Shanlan rice vinegar first increases and then decreases. The results show that at 28℃, Shanlan rice vinegar has the highest sensory score, with a sensory score of 88.60 points. This is because under certain conditions, the fermentation temperature of the lees will make the yeast and lactic acid bacteria more active, and the fermentation speed will be faster, which can make the taste of Shanlan rice vinegar more intense. At 30℃, the sensory score of the lees is the lowest, because too high a temperature will increase the acidity of the lees and make the taste sour, thus affecting the sensory quality and taste of alcohol.

[0139] ③Effects of different fermentation times on the sensory quality of Shanlan rice

[0140] like Fig.16 As shown in the figure, under different fermentation time conditions of Shanlan rice vinegar, the sensory quality score of Shanlan rice showed a trend of first increasing and then decreasing. When the fermentation time of Shanlan rice was 120h, the sensory score reached a peak and then decreased. When the fermentation time of Shanlan rice was 120h, the taste was better, and the sensory score was 87.60 points at this time, and the total acid was 4.8g / 100ml. Studies have shown that when the total acid reaches 4.64g / 100ml, it tends to be stable, and the vinegar mash provides nutrients for the growth and reproduction of microorganisms. Acetic acid bacteria grow and reproduce in large quantities, converting some compounds in the raw materials into acidic substances. When the fermentation time was 72h, the total acid was measured to be 3.6g / 100ml, and the sour taste of Shanlan rice did not meet the sensory quality requirements, thus affecting the sensory quality.

[0141] ④Effects of different fermentation temperatures on the sensory quality of Shanlan rice

[0142] Depend on Fig.17It can be seen that as the fermentation temperature of Shanlan rice increases, the sensory score of Shanlan rice vinegar first increases and then decreases. When the fermentation temperature of Shanlan rice vinegar is 30℃, the sensory score is the highest, which is 89.60 points. This shows that the acetic acid bacteria will make the taste of Shanlan rice vinegar the best at a suitable temperature; the sensory score is the lowest at 26℃, because the low temperature cannot reach the fermentation temperature of Shanlan rice vinegar, which affects the sensory quality requirements.

[0143] ⑤The influence of different material ratios on the quality of Shanlan rice

[0144] Depend on Fig.18 It can be seen from the data that with the gradual increase in the proportion of materials, the sensory quality score of Shanlan rice vinegar first increases and then decreases. When the material ratio is 3:7, the sensory score reaches its peak, which is 81.20 points. When the material ratio is 1:9, the sensory score is the lowest. Because the low glutinous rice content will make the Shanlan rice vinegar taste poor, the highest proportion of Shanlan rice will cause the Shanlan rice vinegar to be too dark in color, and the taste difference will become larger, thus affecting the sensory quality.

[0145] ⑥Effect of different material-liquid ratio on sensory quality of Shanlan rice vinegar

[0146] from Fig.19 It can be seen that the sensory quality score of Shanlan rice vinegar first increases and then decreases with the increase of the material-liquid ratio. When the material-liquid ratio is 2:1, the sensory evaluation value is the highest, which is 88.20 points; when the material-liquid ratio is 1:1, the sensory score is the lowest. Because the ratio of Shanlan rice vinegar material to water is unbalanced during the production process, the Shanlan rice vinegar will ferment poorly during the fermentation process, which will eventually affect the taste of the Shanlan rice vinegar.

[0147] Single factor experimental design of seasoning formula

[0148] Based on the above experiments, a single factor experiment was conducted with the amount of yellow lantern pepper (1g, 1.5g, 2g, 2.5g, 3g), the amount of red lantern pepper (5g, 6g, 7g, 8g, 9g), the amount of white sugar (10g, 11g, 12g, 13g, 14g), the amount of MSG (8g, 9g, 10g, 11g, 12g), and the amount of salt (13g, 14g, 15g, 16g, 17g) as influencing factors and the sensory score as the evaluation index to obtain the optimal mixing formula of the seasoning.

[0149] Results and analysis of single factor test on seasoning formula

[0150] ①Effects of different addition amounts of yellow bell pepper on the quality of Shanlan rice vinegar base

[0151] Fig. 20As shown in the figure, with the increase of the amount of yellow lantern pepper added, the sensory quality score of the Shanlan rice vinegar base first increases and then decreases, among which 3g of addition has the best effect, and the sensory score is 84 points. Because the yellow lantern pepper has a special peppery aroma, when the amount is 3g, the color and taste of the base can be made more attractive; when the amount is 2g, the sensory score is the lowest. Adding a small amount of yellow lantern pepper will make the taste of the Shanlan rice vinegar base lighter, the color difference will become larger, and eventually the taste of the base will deteriorate, and a base with good flavor cannot be obtained.

[0152] ②Effects of different addition amounts of red bell pepper on the quality of Shanlan rice vinegar base

[0153] Depend on Fig.21 It can be seen that when the amount of red bell pepper added is 10g, the prepared Shanlan rice vinegar base has the best sensory quality, with a sensory score of 84.90 points. This is because when the red bell pepper is added in a certain amount, it can increase its spiciness and improve the taste. However, when the amount of red bell pepper added is 8g, the taste of the base will become lighter and the color will not meet the sensory requirements, thus affecting the sensory quality of the base.

[0154] ③Effects of different amounts of added white sugar on the quality of Shanlan rice vinegar base

[0155] like Fig. 22 As shown in the figure, the sensory quality score of Shanlan rice vinegar base first increases and then decreases with the increase of its added amount, reaching a peak when the added amount is 20g, at which time the sensory score is 84.10 points; the sensory score is lowest when the added amount is 18g because the white sugar content is too low, which will make the base lack the umami flavor and desired taste.

[0156] ④The effect of different amounts of MSG on the quality of Shanlan rice vinegar base

[0157] like Fig.23 As shown in the figure, the sensory quality score of Shanlan rice vinegar base increases first and then decreases with the increase of its addition amount, reaching a peak at 17g, at which the sensory score is 80.60 points. The glutamic acid contained in MSG can form a complex with the amino acids in the base, increase its umami taste, and can improve the flavor of the base and increase the deliciousness of the soup. The sensory score is the lowest when the amount of MSG added is 15g, because too low an amount of MSG added will affect the flavor and sensory quality of the soup.

[0158] ⑤Effect of different amounts of salt added on the quality of Shanlan rice vinegar base

[0159] from Fig.24It can be seen that the sensory quality score of the Shanlan rice vinegar base increases with the increase in the number of grams of salt added to the base, and then decreases. At 25g, the sensory evaluation value reaches a peak, and the sensory score is 86.10 points. Because salt has the functions of helping sourness, sweetness and freshness, and because of its high osmotic pressure, it can penetrate into the base, thereby increasing the water holding capacity of protein in the cells and causing local protein denaturation, which helps to regulate the quality of the base and improve its taste. When the amount of salt added is 27g, the sensory score of the Shanlan rice vinegar base is the lowest, because the high salt content will make the soup base salty, which does not meet the public taste, thus affecting the sensory quality of the base.

[0160] Index determination

[0161] Sensory evaluation standards

[0162] After the Shanlan rice vinegar was made, it was subjected to sensory evaluation from inside to outside. A scoring team was formed by ten students from the School of Food Science and Engineering. These ten students all had certain basic knowledge of sensory scoring. They scored the color, aroma, taste and flavor of the Shanlan rice vinegar. The total score of the sensory scoring of the quality of the Shanlan rice vinegar was the sum of the scores of each evaluation item. Finally, the average of the sum of the scores of the ten students was the sensory quality scoring table of the condiment. See Table 5.

[0163] Table 5 Sensory quality scoring criteria of Shanlan rice vinegar

[0164]

[0165] With reference to relevant rice wine evaluation methods and sensory evaluation standards, the evaluation was completed by 10 students majoring in food nutrition and inspection education, using a 100-point system. Each reviewer scored in turn with reference to the vinegar evaluation standards in Table 6, and the average score was used as the total score of the vinegar.

[0166] Table 6 Grading criteria for sensory quality of dregs

[0167]

[0168] Analysis and verification of optimal conditions

[0169] The response surface analysis method was used to analyze the data in Table 7 and establish the regression equation of sensory score: R1 = +89.78 + 3.48*A-2.87*B-1.45*C+1.37*D+0.95*AB-3.05*

[0170] ^

[0171] AC+1.55*AD-3.08*BC+3.15*BD+0.22*CD-5.87*A 2-6.11*

[0172] ^^^

[0173] B 2-3.67*C 2-7.19*D 2

[0174] The variance analysis of the obtained regression equation is shown in Table 7.

[0175] Table 6 Analysis of variance for each item of the regression equation

[0176]

[0177]

[0178] Note: P < 0.01 is extremely significant, indicated by **; P < 0.05 is significant, indicated by *; P > 0.05 is not significant.

[0179] As shown in Table 7, the model P < 0.0001, which is extremely significant; its determination coefficient R 2 =0.9976, corrected determination coefficient Adj.R=0.9953, which means that the model fits the actual situation well, so there is a great correlation between the predicted value and the measured value. The lack of fit term P=0.9824>0.05, the data is not significant, which means that other factors that cannot be ignored have little effect on the test results. The coefficient of dispersion (CV) indicates the accuracy of the test. If the value of the coefficient of dispersion is smaller, it can be said that the reliability of the test results is higher. The CV of this test is 0.4604%, which is within an acceptable range. This shows that the test operation is accurate and credible, and the regression equation can also be used to predict and analyze the sensory evaluation of Shanlan rice vinegar. At the same time, react A, B, C, D, AB, AC, AD, BC, BD and A in the quadratic term 2 , B 2 , C 2 , D 2 All of them are extremely significant factors, while C is a significant factor. The results show that at the selected factor level, the established model has certain practical value.

[0180] Determination of physical and chemical indexes of mountain rice

[0181] Total acid determination: Refer to GB12456-2021 "National Food Safety Standard Determination of Total Acid in Food", the total acid was determined by acid-base titration method.

[0182] Fat determination: With reference to GB5009.5-2016 "National Food Safety Standard Determination of Fat in Food", the fat of Shanlan rice vinegar was determined using the Soxhlet extraction method.

[0183] pH measurement: pH meter was used for measurement.

[0184] Determination of alcohol content: refer to GB5009.225-2023 "National Food Safety Standard Determination of Ethanol Concentration in Wines and Edible Alcohol".

[0185] Determination of microorganisms: refer to GB4789.3-2016 "National Food Safety Standard Food Microbiology Examination Coliform Count".

[0186] Physical and chemical index results

[0187] Table 8

[0188]

[0189] It can be seen from Table 8 that the total acid content of Shanlan rice vinegar is 3.35g / 100ml, which is higher than that of traditional condiment vinegar (2.20g / 100ml). This may be due to the influence of acidic substances such as lactic acid and acetic acid produced by the fermentation of Shanlan rice in the process of making Shanlan rice vinegar; the fat content was measured to be 17.74%. Since no additional substances with high fat content are added, but it is only made of raw and auxiliary materials with low fat content, the fat content of this seasoning is lower than that of seasonings on the market; the measured pH is 3.61; the alcohol content is 0.31%vol. Because one of the raw materials of Shanlan rice vinegar is distiller's grains, the base material contains a certain amount of alcohol; the coliform count is ≤6CFU / 100ml, which meets the standards of DBS50 / 022-2021 "Local Standard Condiments for Food Safety", ensuring the safety and quality of Shanlan rice vinegar, so that consumers can eat it with confidence.

[0190] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A mountain blue rice vinegar, characterized in that The raw material components include: Glutinous rice, mountain rice, wine yeast, acetic acid bacteria and seasoning; The mass ratio of the glutinous rice, mountain rice, wine yeast, acetic acid bacteria and seasoning is 1750:750:25:1:1875.

2. The rice vinegar according to claim 1, characterized in that: The seasoning agent consists of monosodium glutamate, salt, white sugar, yellow bell pepper and red bell pepper, and the mass ratio of monosodium glutamate, salt, white sugar, yellow bell pepper and red bell pepper is 17:25:20:3:

10.

3. A method for preparing mountain rice vinegar, characterized in that: The following steps are involved: Step 1: Mix glutinous rice and mountain rice in a mass ratio of 7:3 and wash them clean to obtain mixed rice for later use; Step 2: adding water to the mixed rice in step 1 and soaking for 6 to 8 hours to obtain soaked rice; Step 3: Add water to the soaked rice in step 2 and steam for 30 minutes to obtain steamed rice; The mass ratio of the soaked rice to water is 2:1; Step 4: Cool the steamed rice in step 3 to reduce the temperature of the steamed rice to 28-32° C. to obtain cooled rice; Step 5: adding distiller's yeast and water to the cooled rice in step 4, fermenting to obtain distiller's grains, heating at 85° C. for 30 minutes, then cooling to room temperature, adding acetic acid bacteria, and obtaining rice to be fermented; The mass ratio of the koji, water and glutinous rice is 1:10:70; and the mass ratio of the koji to acetic acid bacteria is 25:1; Step 6: fermenting the rice to be fermented in step 5 to obtain fermented rice vinegar; Step 7: adding the flavoring agent to the fermented rice vinegar in step 6, crushing and stirring to mix well, to obtain a preliminary product of Shanlan rice vinegar; Step 8: Heat the preliminary Shanlan rice vinegar product in step 7 to 100° C., dissolve for 5 minutes, and stir evenly to obtain the finished Shanlan rice vinegar.

4. The method for preparing mountain rice vinegar according to claim 3, characterized in that: In step 2, the height between the water surface and the surface of the mixed rice is 10 cm.

5. The method for preparing mountain rice vinegar according to claim 3, characterized in that: In step 5, the fermentation temperature is 28° C. and the fermentation time is 72 hours.

6. The method for preparing mountain rice vinegar according to claim 3, characterized in that: In step 6, the fermentation temperature is 26-34° C., and the fermentation time is 70-170 hours.

7. The method for preparing mountain rice vinegar according to claim 3, characterized in that: In step 7, the mass ratio of the seasoning to the mountain rice is 5:2.

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