Highland barley rice and preparation method thereof

Abstract

The invention belongs to the technical field of food processing, and discloses highland barley and a preparation method thereof. According to the preparation method, the cooking time of the highland barley can be shortened, the highland barley can be cooked together with rice, the cooked highland barley has better eating quality, nutritional ingredients of the highland barley can be reserved to the maximum extent, and the problem that nutrient substances of the highland barley are lost due to traditional long-time soaking or pre-cooking treatment is solved. The preparation method is suitable for preparing any kind of highland barley, including black highland barley, white highland barley and the like, the prepared highland barley has rich nutrient substances and active substances and better oxidation resistance, and the highland barley still has better quality after being packaged in vacuum and stored at normal temperature for 12 months.

Description

Technical Field

[0001] The invention relates to the technical field of food processing, and in particular to highland barley rice and a preparation method thereof. Background Art

[0002] Highland barley, also known as hullless barley or naked barley, is a cereal crop of the genus Hordeum in the Poaceae family. It is mainly grown in the Qinghai-Tibet Plateau and its surrounding areas. It can withstand poor and cold environments and is the only crop that can mature normally in high-altitude cold areas above 4,500 m above sea level. Highland barley has the characteristics of high protein, high fiber, high vitamins, low fat and low sugar. It also contains a variety of active substances such as β-glucan, polyphenols, and γ-aminobutyric acid. It is a food crop that can be used as both medicine and food, and a traditional food for the Tibetan people. In recent years, with the adjustment and changes in people's dietary structure, highland barley, which is rich in nutrients, has gradually become known to the public and is widely used in food processing such as pasta products, baked products, and beverage products.

[0003] Highland barley is a product made by cleaning, peeling, grading and color sorting highland barley. Compared with traditional staple rice, highland barley is more nutritious and balanced. However, when highland barley is steamed, due to the dual obstacles of the endosperm cell wall, it is difficult for water to penetrate into the rice grains, resulting in poor steaming performance. After steaming, it is hard and has a poor taste, which makes it difficult to meet the demand of being cooked and cooked at the same time as rice, thus limiting the promotion of highland barley as a staple food. Soaking highland barley for a long time or pre-cooking it can make it cooked and cooked at the same time as rice, but the above method is not only time-consuming, but may also cause the dissolution of nutrients such as water-soluble β-glucan and the growth of microorganisms, reducing the edible quality. Summary of the invention

[0004] Based on the above reasons, the object of the present invention is to provide a highland barley rice and a preparation method thereof, the preparation method can retain the nutritional components of highland barley rice grains to the maximum extent, the prepared highland barley rice can be cooked together with rice, and after vacuum packaging, it still has good quality after being stored at room temperature for 12 months.

[0005] In order to achieve the above object, in a first aspect, the present invention provides a method for preparing highland barley rice, comprising the following steps: The highland barley is peeled to obtain highland barley bran and highland barley grains; Water is added to highland barley bran, plant lactobacillus and yeast are inoculated to perform a first fermentation, and then a complex enzyme is added to perform a second fermentation to obtain a fermentation liquid; placing highland barley grains in a fermentation liquid, inoculating Rhizopus stolonifer and Aspergillus oryzae for a third fermentation, and performing a short-term high-temperature and high-pressure treatment after the fermentation is completed to obtain fermented rice; The fermented rice is quickly cooled and then subjected to a two-stage drying process to obtain highland barley rice.

[0006] Furthermore, the temperature of the first fermentation and the second fermentation is 28-32°C, the total fermentation time is 20-24 hours, and the time of the first fermentation accounts for 65%-70% of the total fermentation time.

[0007] Furthermore, the temperature of the third fermentation is 28-30°C and the time is 8-10 hours.

[0008] Furthermore, the complex enzyme includes xylanase and glucanase.

[0009] Furthermore, the inoculation amounts of the plant lactobacillus and yeast are 0.6%-0.8% and 1%-1.5% of the total mass of highland barley bran and water, respectively.

[0010] Furthermore, the inoculation amounts of Rhizopus stolonifer and Aspergillus oryzae are 0.5%-0.8% and 0.8%-1% of the total mass of highland barley grains and fermentation liquid, respectively.

[0011] Furthermore, the temperature of the high temperature and high pressure treatment is 80-90°C, the pressure is 102-104 kPa, and the time is 45-65 s.

[0012] Furthermore, the ambient humidity of the two-stage drying treatment is 38%-42%, the temperature of the first stage drying treatment is 60-65°C, and the fermented rice is dried to a moisture content of 30%-32%, and the temperature of the second stage drying treatment is 35-45°C, and the fermented rice is dried to a moisture content of 12%-15%.

[0013] In a second aspect, the present invention provides highland barley rice prepared according to the aforementioned method for preparing highland barley rice.

[0014] Furthermore, the highland barley rice is packaged in a vacuum manner.

[0015] The beneficial effects of the present invention are: The preparation method of the present invention can make the arrangement of highland barley rice starch particles loose, form water channels, easily absorb water during cooking, and can promote the uniform penetration of water inside the highland barley rice, so as to shorten the cooking time of the highland barley rice, so that the highland barley rice can be cooked and cooked at the same time as rice, and has better edible quality after cooking.

[0016] The preparation method of the invention can solve the problem of loss of nutrients in highland barley rice due to traditional long-term soaking or pre-cooking treatment, retain the nutrients of highland barley rice to the maximum extent, avoid infection by harmful microorganisms, and ensure that the highland barley rice has good edible quality after steaming.

[0017] The invention is applicable to the preparation of any kind of highland barley rice, and the prepared highland barley rice has good anti-oxidation performance and still has good quality after being stored at room temperature for 12 months after vacuum packaging. When the raw material is white highland barley, the highland barley rice product finally obtained is light white and bright in color. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical scheme and advantages of the present invention clearer, the scheme of the present invention is further described in detail below in conjunction with embodiment.It will be appreciated by those skilled in the art that the following examples are exemplary only, and are not intended to limit the scope of the present invention.In addition, in the following description, those not indicating specific conditions in the examples are carried out according to the conditions of normal conditions or manufacturer's recommendations.Reagents used or instruments not indicating manufacturers are conventional products that can be obtained by commercial purchase.

[0019] The first embodiment of the present invention provides a method for preparing highland barley rice, comprising the following steps: The highland barley is peeled to obtain highland barley bran and highland barley grains; Water is added to highland barley bran, plant lactobacillus and yeast are inoculated to perform a first fermentation, and then a complex enzyme is added to perform a second fermentation to obtain a fermentation liquid; placing highland barley grains in a fermentation liquid, inoculating Rhizopus stolonifer and Aspergillus oryzae for a third fermentation, and performing a short-term high-temperature and high-pressure treatment after the fermentation is completed to obtain fermented rice; The fermented rice is quickly cooled and then subjected to a two-stage drying process to obtain highland barley rice.

[0020] In this embodiment, the highland barley can be any variety of highland barley, such as black highland barley, white highland barley, etc.

[0021] In the first fermentation system, the mass ratio of highland barley bran to water is 1:(0.8-1), and the inoculation amounts of Lactobacillus plantarum and yeast are 0.6%-0.8% and 1%-1.5% of the total mass of highland barley bran and water, respectively.

[0022] The temperature of the first fermentation and the second fermentation is 28-32 ℃, the total fermentation time is 20-24 h, and the time of the first fermentation accounts for 65%-70% of the total fermentation time. The compound enzyme added to the second fermentation system is obtained by mixing xylanase and glucanase in a mass ratio of 1: (1.2-1.5), and the addition amount is 1%-1.5% of the total mass of highland barley bran and water. Under the joint action of the two-stage fermentation treatment and the compound enzyme, after the second fermentation is completed, a fermentation liquid with a certain number of viable bacteria and active substances can be obtained by filtration treatment. The fermentation liquid is conducive to the subsequent rapid fermentation of highland barley rice grains, and at the same time, it can improve the antioxidant capacity of highland barley rice grains during fermentation and subsequent treatment, thereby avoiding the highland barley rice grains from turning yellow and producing odor due to excessive fermentation time or oxidation, and the quality is reduced.

[0023] It should be noted that the time of adding the complex enzyme should not be too early or too late, that is, the time of the first fermentation should not be too long or too short. If the first fermentation time accounts for less than 65% of the total fermentation time, the number of live bacteria and the content of active substances in the fermentation liquid will be reduced, which is not conducive to the subsequent rapid fermentation of highland barley rice grains and the improvement of their antioxidant capacity; if it is higher than 70%, the content of active substances in the fermentation liquid will still be reduced, which is not conducive to improving the antioxidant capacity of highland barley rice grains in subsequent processing.

[0024] In the third fermentation system, the mass ratio of highland barley rice grains to fermentation liquid is 1: (1-1.2), and the inoculation amount of Rhizopus stolonifer and Aspergillus oryzae is 0.5%-0.8% and 0.8%-1% of the total mass of highland barley rice grains and fermentation liquid, respectively. Based on the presence of fermentation liquid, the fermentation speed of highland barley rice grains is significantly accelerated. Fermentation is carried out at 28-30 ° C for 4-6 h. During the fermentation process, a variety of chemical changes will occur, making the arrangement of highland barley rice grain starch granules loose, forming water channels, and making the obtained highland barley rice easy to absorb water during cooking, and promoting the uniform penetration of water inside the highland barley rice, so as to achieve the purpose of shortening the cooking time of highland barley rice, so that it can be cooked and cooked together with rice. It should be noted that if the third fermentation time is too short, the purpose of significantly shortening the cooking time of highland barley rice cannot be achieved, and it cannot be cooked and cooked together with rice; if the fermentation time is too long, the cooking time of highland barley rice will be excessively shortened, and it still cannot be cooked and cooked together with rice. It should also be noted that the effect of the third fermentation can be achieved under the joint action of Rhizopus and Aspergillus. Only using Rhizopus or Aspergillus to ferment highland barley rice grains cannot achieve the effect described in this embodiment.

[0025] In this embodiment, the purpose of short-term high temperature and high pressure treatment after the third fermentation is to reduce or inactivate the activity of the fermentation bacteria in the fermentation system to prevent the highland barley rice from being over-fermented. In addition, the activity of lipase, lipoxygenase, etc. in the highland barley rice can be reduced or inactivated to prevent the highland barley rice from oxidizing and deteriorating during storage. The temperature of the short-term high temperature and high pressure treatment is 80-90 ° C, the pressure is 102-104 kPa, and the time is 45-65 s. It should be noted that the objects of the short-term high temperature and high pressure treatment are fermented rice and fermentation liquid. The fermented rice cannot be treated with short-term high temperature and high pressure alone, otherwise it will cause the loss of nutrients, and at the same time, the cooking time will be excessively shortened, and it is still impossible to cook and cook with rice. After the short-term high temperature and high pressure treatment, the fermented rice is filtered.

[0026] It should be noted that the purpose of rapidly cooling the fermented rice is also to prevent it from being ripened. The method of rapidly cooling the rice is to place the highland barley rice at 0-4°C for cooling.

[0027] It is understandable that long-term high temperature and high pressure treatment is also easy to cause the fermented rice to be matured, so the aforementioned high temperature and high pressure treatment time is relatively short, and the shorter treatment may still leave a small amount of fermentation bacteria and enzymes in the fermented rice, affecting the quality of highland barley rice. Therefore, in this embodiment, the fermented rice is subjected to a first stage of drying treatment at 60-65 ° C after cooling treatment, so that the fermentation bacteria and enzymes remaining in the fermented rice are further reduced in activity or inactivated. Therefore, the highland barley rice is quickly cooled to 60-65 ° C, and after cooling, it is directly placed at 60-65 ° C for the first stage of drying treatment, and dried to a moisture content of 30%-32% for the fermented rice, and then placed at 35-45 ° C for the second stage of drying treatment, and dried to a moisture content of 12%-15% for the fermented rice, to obtain highland barley rice. The environmental humidity of the first stage of drying treatment and the second stage of drying treatment is 38%-42%. The second embodiment of the present invention provides highland barley rice prepared according to the above-mentioned preparation method. The packaging method of the highland barley rice is vacuum packaging.

[0028] The highland barley rice of this embodiment has full grains, can be cooked together with rice, and has good anti-oxidation performance. After vacuum packaging, the shelf life at room temperature can reach more than 12 months, and the storage quality is good.

[0029] Specific embodiments for implementing the present invention will be disclosed below, as well as corresponding comparative examples to demonstrate the relevant technical effects of the present invention.

[0030] The present invention is applicable to the preparation of any type of highland barley rice such as black highland barley rice and white highland barley rice. The following embodiment is for the preparation of white highland barley rice.

[0031] Example 1 Preparation of white highland barley rice The white highland barley is peeled to obtain highland barley bran and highland barley grains; According to the mass ratio of highland barley bran to water of 1:0.8, water was added to highland barley bran, and 0.6% of the total mass of highland barley bran and water was inoculated with plant lactobacillus and 1% of yeast, and the first fermentation was carried out at 28 ℃ for 13 h, and then 1% of the total mass of highland barley bran and water was added with complex enzyme (xylanase and glucanase were mixed at 1:1.2), and the second fermentation was carried out at 28 ℃ for 7 h. After the fermentation was completed, the fermentation liquid was filtered; According to the mass ratio of highland barley grains to fermentation liquid of 1:1, highland barley grains were placed in the fermentation liquid, and 0.5% of the total mass of highland barley grains and fermentation liquid were inoculated with Rhizopus stolonifer and 0.8% of Aspergillus oryzae, and the third fermentation was carried out at 28 ℃ for 4 h. After the fermentation was completed, the high temperature and high pressure treatment was carried out at 80 ℃ and 102 kPa for 45 s, and then the fermented rice was filtered; The fermented rice was placed at 0°C and rapidly cooled to 60°C. After cooling, the fermented rice was subjected to the first drying process at 60°C and an ambient humidity of 38% until the moisture content reached 30%. The fermented rice was then subjected to the second drying process at 35°C and an ambient humidity of 38% until the moisture content reached 12%, thereby obtaining white highland barley rice.

[0032] Example 2 Preparation of white highland barley rice The white highland barley is peeled to obtain highland barley bran and highland barley grains; According to the mass ratio of highland barley bran to water of 1:0.9, water was added to highland barley bran, and 0.7% of the total mass of highland barley bran and water were inoculated with plant lactobacillus and 1.3% of yeast, and the first fermentation was carried out at 30 ℃ for 14.5 h, and then 1.2% of the total mass of highland barley bran and water (xylanase and glucanase were mixed at a ratio of 1:1.3) were added, and the second fermentation was carried out at 30 ℃ for 7.5 h. After the fermentation was completed, the fermentation liquid was filtered; According to the mass ratio of highland barley grains to fermentation liquid of 1:1.1, highland barley grains were placed in the fermentation liquid, and 0.6% of the total mass of highland barley grains and fermentation liquid was inoculated with Rhizopus stolonifer and 0.9% of Aspergillus oryzae. The third fermentation was carried out at 29 ℃ for 5 h. After the fermentation was completed, the high temperature and high pressure treatment was carried out at 85 ℃ and 103 kPa for 50 s, and then the fermented rice was filtered; The fermented rice was placed at 2°C and rapidly cooled to 62°C. After cooling, the fermented rice was subjected to the first drying process at 62°C and an ambient humidity of 40% until the moisture content reached 31%. The fermented rice was then subjected to the second drying process at 40°C and an ambient humidity of 40% until the moisture content reached 13%, thereby obtaining white highland barley rice.

[0033] Example 3 Preparation of white highland barley rice The white highland barley is peeled to obtain highland barley bran and highland barley grains; According to the mass ratio of highland barley bran to water of 1:1, water was added to highland barley bran, 0.8% of the total mass of highland barley bran and water were inoculated with Lactobacillus plantarum and 1.5% of yeast, and the first fermentation was carried out at 32 ℃ for 16.5 h, and then 1.5% of the total mass of highland barley bran and water was added with complex enzyme (xylanase and glucanase were mixed at a ratio of 1:1.5), and the second fermentation was carried out at 32 ℃ for 7.5 h. After the fermentation was completed, the fermentation liquid was filtered; According to the mass ratio of highland barley grains to fermentation liquid of 1:1.2, highland barley grains were placed in the fermentation liquid, and 0.8% of the total mass of highland barley grains and fermentation liquid was inoculated with Rhizopus stolonifer and 1% of Aspergillus oryzae. The third fermentation was carried out at 30 ℃ for 6 h. After the fermentation was completed, the high temperature and high pressure treatment was carried out at 90 ℃ and 104 kPa for 65 s, and then the fermented rice was filtered; The fermented rice was placed at 4°C and rapidly cooled to 65°C. After cooling, the fermented rice was subjected to the first drying process at 65°C and an ambient humidity of 42% until the moisture content was 32%. Thereafter, the fermented rice was subjected to the second drying process at 45°C and an ambient humidity of 42% until the moisture content was 15%, thereby obtaining white highland barley rice.

[0034] Example 4 The preparation method is the same as that in Example 1, the difference is that the first fermentation time in Example 1 is 14 h, and the second fermentation time is 6 h.

[0035] Example 5 The preparation method is the same as that in Example 1, except that the time for the third fermentation in Example 5 is 6 h.

[0036] Comparative Example 1 The difference from Example 1 is that the preparation of fermentation liquid is cancelled, highland barley grains are placed in water, and Rhizopus stolonifer and Aspergillus oryzae are inoculated for fermentation treatment.

[0037] Comparative Example 2 The difference from Example 1 is that the addition of complex enzyme is eliminated.

[0038] Comparative Example 3 The difference from Example 1 is that the first fermentation time is 12.5 h, and the second fermentation time is 7.5 h.

[0039] Comparative Example 4 The difference from Example 1 is that the time of the first fermentation is 14.5 h, and the time of the second fermentation is 5.5 h.

[0040] Comparative Example 5 The difference from Example 1 is that the time of the third fermentation is 3.5 h.

[0041] Comparative Example 6 The difference from Example 1 is that the time of the third fermentation is 6.5 h.

[0042] Comparative Example 7 The difference from Example 1 is that Rhizopus stolonifer is replaced by Aspergillus niger.

[0043] Comparative Example 8 The difference from Example 1 is that Aspergillus oryzae is replaced by Rhizopus oryzae.

[0044] Comparative Example 9 The difference from Example 1 is that the high temperature and high pressure and rapid cooling treatments are eliminated, the fermented rice is filtered after the third fermentation is completed, and the fermented rice is directly subjected to the first drying treatment.

[0045] Comparative Example 10 The difference from Example 1 is that after the third fermentation is completed, the fermented rice is first filtered to obtain the fermented rice, and then the fermented rice is subjected to a short-time high-temperature and high-pressure treatment.

[0046] Comparative Example 11 The difference from Example 1 is that the conditions of the first stage of drying treatment are 35° C. and 38% humidity.

[0047] Test Example 1 This test example mainly measures the whiteness, nutrient content, active substance content and antioxidant performance of the white highland barley rice samples of the embodiment and the comparative example, and takes the untreated white highland barley rice grains as the control group. The specific index detection method is as follows: Whiteness: The whiteness is measured by a whiteness meter. Before the measurement, the instrument is calibrated using white and brown calibration plates. Then, some samples are randomly selected and put into the instrument slot and fastened for measurement. The transmittance (%), whiteness (%) and whiteness (%) of each group of white highland barley rice samples are recorded.

[0048] Protein content: refer to GB 5009.5-2016 "National Food Safety Standard Determination of Protein in Food".

[0049] Fat content: refer to GB 5009.6-2016 "National Food Safety Standard Determination of Fat in Foods".

[0050] Determination of dietary fiber content: refer to GB 5009.88-2023 "National Food Safety Standard Determination of Dietary Fiber in Food".

[0051] Total phenol content: The total phenol content was determined by the Folin phenol method. The gallic acid standard was diluted with distilled water to 0.0125 mg / mL, 0.025 mg / mL, 0.05 mg / mL, 0.1 mg / mL, 0.2 mg / mL, and 0.3 mg / mL to obtain standard solutions of different concentrations. The absorbance of the standard solutions of different concentrations was measured at a wavelength of 760 nm. The concentration of the standard solution was used as the horizontal axis and the corresponding absorbance value was used as the vertical axis. The standard curve was drawn and the standard equation was calculated; After the white highland barley rice sample was crushed, 2 g of the crushed sample was weighed, and 20 mL of 80% methanol was added. Ultrasonic extraction was performed at 60°C and 300 W for 20 min. After the extraction was completed, it was centrifuged at 8000 rpm for 10 min. 20 μL of the supernatant (i.e., the extract) was taken, 20 μL of Folin phenol reagent was added, mixed and allowed to stand for 5 min, and then 80 μL of 10% Na2CO3 solution was added. After reacting at room temperature in the dark for 60 min, the absorbance was measured at 765 nm, and the measured absorbance value was substituted into the above standard equation to calculate the concentration. The total phenol content was calculated based on the concentration. The calculation formula is as follows: Total phenol content (mg / g) = x f ×V f / w f Where: x f is the calculated concentration, mg / mL; V f is the total volume of the extract, mL; W f is the sample mass, g.

[0052] Total flavonoid content: The total flavonoid content was determined by NaNO2-Al(NO3)3-NaOH colorimetry. The rutin standard was diluted with distilled water to 0.05 mg / mL, 0.1 mg / mL, 0.2 mg / mL, 0.4 mg / mL, 0.8 mg / mL, and 1.0 mg / mL to obtain standard solutions of different concentrations. The absorbance of the above standard solutions of different concentrations was measured at a wavelength of 510 nm. The standard solution concentration was used as the horizontal coordinate and the corresponding absorbance value was used as the vertical coordinate. The standard curve was drawn and the standard equation was calculated. The white highland barley rice sample was crushed, 2 g of the crushed sample was weighed, 20 mL of 80% methanol was added, and ultrasonic extraction was performed at 60°C and 300 W for 20 min. After the extraction was completed, it was centrifuged at 8000 rpm for 10 min, 20 μL of the supernatant (i.e., the extract) was taken, 10 μL of 25% (m / v) NaNO2 solution was added to react for 6 min, and then 10 μL of 10% AlCl3 solution was added to react for 5 min, and 30 μL of 1 mol / L NaOH solution was added to measure the absorbance at 510 nm, and the measured absorbance value was substituted into the above standard equation to calculate the concentration. The total flavonoid content was calculated according to the concentration. The calculation formula is as follows: Total flavonoid content (mg / g) = x t ×V t / w t Where: x t is the calculated concentration, mg / mL; V t is the total volume of the extract, mL; Wt is the sample mass, g.

[0053] β-glucan content: crush the white highland barley rice sample, weigh 0.1 g of the crushed sample into a 15 mL centrifuge tube, add 0.2 mL of 50% ethanol solution and mix well, then add 4 mL of phosphate buffer (20 mmol / L, pH 6.5) and mix well, heat in a boiling water bath for 5 min, take out and mix well on a vortex oscillator every half a minute to prevent it from agglomerating, then bathe in 50 ℃ water for 5 min, add 0.2 mL of lichenase (10 U), enzymolysis at 50 ℃ for 1 h, add 5 mL of sodium acetate buffer (200 mmol / L, pH 4.0) and mix well for 5 min, centrifuge at 1000 rpm for 10 min, and take the supernatant as the sample solution to be tested. Use the β-glucan kit to determine the β-glucan content of the sample solution to be tested.

[0054] ABTS free radical scavenging rate, DPPH free radical scavenging rate, hydroxyl free radical scavenging rate: grind the white highland barley rice sample, weigh 50 mg of the grinded sample, add 1 mL of 80% methanol solution, mix thoroughly and extract at 40 °C for 30 min. After the extraction is completed, centrifuge at 8000 rpm for 10 min, and take the supernatant as the extract. The ABTS free radical scavenging ability test kit, DPPH free radical scavenging ability test kit and hydroxyl free radical scavenging ability test kit were used to measure the ABTS free radical scavenging rate, DPPH free radical scavenging rate and hydroxyl free radical scavenging rate of the above extracts.

[0055] The results of the whiteness test of each group of white highland barley rice samples are shown in Table 1.

[0056] Table 1 The results of whiteness test of each group of white highland barley rice samples .

[0057] According to the results in Table 1, the transmittance, whiteness and refined whiteness of the white highland barley rice prepared by the process of the present invention are closest to those of the untreated white highland barley rice grains in the control group, and are light white and translucent in color.

[0058] The results of the determination of the nutrient content of each group of white highland barley rice samples are shown in Table 2.

[0059] Table 2 Nutrient content determination results of each group of white highland barley rice samples .

[0060] According to the results of nutrient content determination in Table 2, compared with the control group, the protein, fat and dietary fiber contents of the white highland barley rice prepared by the process of the present invention are only slightly reduced, indicating that the process of the present invention can minimize the loss of nutrients in white highland barley rice grains.

[0061] The results of the determination of the active substance content of each group of white highland barley rice samples are shown in Table 3.

[0062] Table 3 Determination results of active substance content in each group of white highland barley rice samples .

[0063] According to the results of active substance content determination in Table 3, the contents of total phenols, total flavonoids and β-glucan in white highland barley rice prepared by the process of the present invention are close to those of untreated white highland barley grains in the control group, or even higher than those in the control group, indicating that the process of the present invention can reduce the loss of active substances in white highland barley grains to the greatest extent, and can even increase the content of active substances in white highland barley rice.

[0064] The results of the antioxidant activity test of each group of white highland barley rice samples are shown in Table 4.

[0065] Table 4 Antioxidant activity test results of each group of white highland barley rice samples .

[0066] According to the antioxidant activity test results in Table 4, the overall antioxidant activity of the white highland barley rice prepared by the process of the present invention is higher and higher than that of the control group sample, indicating that the process of the present invention is helpful to improve the antioxidant activity of white highland barley rice.

[0067] Test Example 2 The white highland barley rice samples of the embodiment and the comparative example were vacuum packed and stored at room temperature for 12 months. The fatty acid value, peroxide value and acetaldehyde content were measured every other month by the following methods: Fatty acid value: Determined in accordance with GB / T 15684-2015 "Determination of fatty acid value of milled cereal products"; Peroxide value: Determined in accordance with GB 5009.227-2023 "National Food Safety Standard - Determination of Peroxide Value in Food"; Acetaldehyde content: Determined by headspace solid phase microextraction and gas chromatography-mass spectrometry.

[0068] According to the determination of the above three indicators, the quality changes of white highland barley rice were comprehensively analyzed and recorded, among which: "+" means good quality and no bad smell, and "-" means that the white highland barley rice is rancid. The untreated white highland barley rice grains were used as the control group, and the results are shown in Table 5.

[0069] Table 5 Quality changes of white highland barley rice during 12-month storage after vacuum packaging .

[0070] According to the experimental results in Table 5, the white highland barley rice produced by the process of the present invention still has good quality when stored at room temperature for 12 months.

[0071] Test Example 3 The white highland barley rice samples of the embodiment and the comparative example were subjected to soaking water absorption, optimal cooking time, cooking water absorption and volume expansion rate determination, with untreated white highland barley rice grains as control group 1 and rice as control group 2. The specific determination method is: Water absorption rate by immersion: weigh 5 g of sample, add 250 mL of pure water, soak for 60 min at 30°C, drain the water and wipe off the residual water on the surface of the sample, and calculate the water absorption rate of the sample based on the mass before and after immersion; Optimal cooking time: Weigh an appropriate amount of sample and heat it in boiling water. After cooking for 10 minutes, randomly take out 5 grains of rice every 1 minute to observe their white core. If no white core is observed, it is recorded as the optimal cooking time. Cooking water absorption rate and volume expansion rate: Weigh 10 g of sample, add 200 mL of pure water, heat according to the optimal cooking time of each group of samples, take out the samples after cooking, wipe off the surface moisture, record the mass of the raw materials and the cooked samples and calculate the cooking water absorption rate, then use the water displacement method to determine the volume and calculate the volume expansion rate.

[0072] The test results of soaking water absorption rate, optimal cooking time, cooking water absorption rate and volume expansion rate of each group of samples are shown in Table 6.

[0073] Table 6 Determination results of water absorption rate of each group of samples, optimal cooking time, water absorption rate of cooking and volume expansion rate .

[0074] According to Table 6, the soaking water absorption of the white highland barley rice prepared by the process of the present invention is higher, close to that of rice, indicating that the method adopted by the present invention can make the arrangement of the white highland barley rice starch particles loose, form a moisture channel, and absorb moisture during cooking. The cooking time, cooking water absorption rate, and volume expansion rate of the white highland barley rice of the embodiment are all close to those of the rice sample of control group 2, and can be cooked and cooked with rice. Compared with Example 1 and control group 2, except for comparative examples 2 and 4, the cooking time of other comparative examples is either too long or too short, and they cannot be cooked and cooked with rice.

[0075] Test Example 4 The highland barley rice obtained by cooking the samples of the embodiment, comparative example and control group 1 in Test Example 2 at the optimal cooking time was subjected to a sensory evaluation, and the evaluation method was as follows: 10 trained sensory evaluation personnel were selected to form an evaluation team, and the highland barley rice of each group was scored according to the sensory evaluation criteria in Table 7. The scoring results are shown in Table 8.

[0076] Table 7 Sensory evaluation standard table of highland barley rice .

[0077] Table 8 Sensory evaluation results of highland barley rice after cooking of samples in Example, Comparative Example and Control Group 1 .

[0078] According to the results in Table 8, the white highland barley rice prepared by the process of the present invention has good sensory quality after cooking, and the sensory score is significantly higher than that of each comparative example and control group 1, and the eating experience is better.

[0079] Test Example 5 The hardness of the rice cooked at the optimal cooking time of the samples of the embodiment, control group 1, and control group 2 in Test Example 2 was measured using a texture analyzer. The measurement conditions were: probe model P / 20P, pre-measurement speed 1 mm / s, test speed 0.5 mm / s, post-measurement speed 1 mm / s, compression ratio 70%, 2 compression intervals 5 s, each sample was measured 3 times in parallel, and the results were averaged. The measurement results are shown in Table 9.

[0080] Table 9 Results of hardness test of cooked rice in Example, Control Group 1 and Control Group 2 .

[0081] According to the results in Table 9, it can be seen that the white highland barley rice prepared by the process of the present invention has a hardness close to that of the rice sample in the control group 2 after cooking, and has a soft taste.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing highland barley rice, characterized in that: The following steps are involved: The highland barley is peeled to obtain highland barley bran and highland barley grains; Water is added to highland barley bran, plant lactobacillus and yeast are inoculated to perform a first fermentation, and then a complex enzyme is added to perform a second fermentation to obtain a fermentation liquid; placing highland barley grains in a fermentation liquid, inoculating Rhizopus stolonifer and Aspergillus oryzae for a third fermentation, and performing a short-term high-temperature and high-pressure treatment after the fermentation is completed to obtain fermented rice; The fermented rice is quickly cooled and then subjected to a two-stage drying process to obtain highland barley rice.

2. The preparation method according to claim 1, characterized in that The temperature of the first fermentation and the second fermentation is 28-32°C, the total fermentation time is 20-24 hours, and the time of the first fermentation accounts for 65%-70% of the total fermentation time.

3. The preparation method according to claim 1, characterized in that: The temperature of the third fermentation is 28-30°C and the time is 4-6 hours.

4. The preparation method according to claim 1, characterized in that: The complex enzyme comprises xylanase and glucanase.

5. The preparation method according to claim 1, characterized in that: The inoculation amounts of the plant lactobacillus and yeast are 0.6%-0.8% and 1%-1.5% of the total mass of highland barley bran and water respectively.

6. The preparation method according to claim 1, characterized in that: The inoculation amounts of Rhizopus stolonifer and Aspergillus oryzae are 0.5%-0.8% and 0.8%-1% of the total mass of highland barley grains and fermentation liquid, respectively.

7. The preparation method according to claim 1, characterized in that: The temperature of the short-time high temperature and high pressure treatment is 80-90° C., the pressure is 102-104 kPa, and the time is 45-65 s.

8. The preparation method according to claim 1, characterized in that: The ambient humidity of the two-stage drying treatment is 38%-42%, the temperature of the first stage drying treatment is 60-65°C, and the fermented rice is dried to a moisture content of 30%-32%. The temperature of the second stage drying treatment is 35-45°C, and the fermented rice is dried to a moisture content of 12%-15%.

9. Highland barley rice prepared by the method for preparing highland barley rice as claimed in any one of claims 1 to 8.

10. The highland barley rice according to claim 9, characterized in that The highland barley rice is packaged in a vacuum manner.