Rice milk coffee beverage and preparation method thereof

Abstract

The invention discloses a rice milk coffee beverage and a preparation method thereof, and belongs to the technical field of coffee beverages. The preparation method of the rice milk coffee beverage comprises the following steps: mixing brown rice milk and glutinous rice milk to obtain mixed rice milk; adding a compound enzyme into the mixed rice milk, and carrying out enzymolysis and pre-gelatinization to obtain pre-gelatinized rice milk, wherein the compound enzyme comprises cellulase and amylase; gelatinizing the pre-gelatinized rice milk to obtain gelatinized rice milk; whey protein powder is added into the gelatinized rice milk for hydration, and homogenization treatment is performed to obtain homogenized rice milk; adding compound bacteria into the homogenized rice milk, and fermenting to obtain fermented rice milk, wherein the compound bacteria comprise saccharomycetes and lactic acid bacteria; the fermented rice milk and coffee are mixed to obtain the rice milk coffee beverage. The prepared rice milk coffee beverage can replace milk to improve bitterness and roughness of coffee, people with lactose intolerance can be cared, discomfort caused by lactose intolerance is reduced, and the rice milk coffee beverage has unique flavor.

Description

Technical Field

[0001] The invention relates to the technical field of coffee beverages, in particular to a rice milk coffee beverage and a preparation method thereof. Background Art

[0002] With the change of eating habits, the coffee market has maintained a steady growth in recent years. Getting rid of sleepiness and replenishing energy are the main purchasing drivers of coffee consumers, and consumers mostly choose to drink it in the morning to refresh themselves. Currently, the mainstream coffee drinks in the market are milk coffee and American black coffee.

[0003] Coffee tastes bitter and rough, and consumers usually add milk to improve the bitterness and roughness of coffee. However, according to literature, 65-75% of people in the world are lactose intolerant, and Chinese people are also a high-risk group. If the taste of coffee is improved by adding milk, people with lactose intolerance will find it difficult to adapt.

[0004] Therefore, it is of research and development significance to develop a new coffee base that can retain the flavor of coffee, replace milk to reduce the irritation of caffeine to the gastric mucosa, and expand the consumer group to include people with lactose intolerance. Summary of the invention

[0005] The main purpose of the present invention is to provide a rice milk coffee beverage and a preparation method thereof, so as to solve the problem that caffeine in traditional coffee beverages irritates gastric mucosa, and the technical problem that adding milk to reduce caffeine irritation to gastric mucosa is unfriendly to lactose intolerant people.

[0006] To achieve the above object, the present invention provides a method for preparing a rice milk coffee beverage, comprising the following steps:

[0007] Mixing brown rice slurry and glutinous rice slurry to obtain mixed rice slurry;

[0008] Adding a composite enzyme to the mixed rice milk for enzymatic pre-gelatinization to obtain pre-gelatinized rice milk, wherein the composite enzyme comprises cellulase and amylase;

[0009] The pre-gelatinized rice milk is gelatinized to obtain gelatinized rice milk;

[0010] adding whey protein powder to the gelatinized rice milk and performing homogenization to obtain homogenized rice milk;

[0011] Adding composite bacteria to the homogenized rice milk for fermentation to obtain fermented rice milk, wherein the composite bacteria includes yeast and lactic acid bacteria;

[0012] The fermented rice milk and coffee are mixed to obtain a rice milk coffee beverage.

[0013] In some embodiments of the present invention, the mass ratio of the brown rice slurry to the glutinous rice slurry is (1-4):1.

[0014] In some embodiments of the present invention, the mass ratio of cellulase to amylase in the composite enzyme is (1:2) to (1:8);

[0015] And / or, based on 100% of the total mass of the mixed rice milk, the added amount of the complex enzyme is 0.05% to 0.3%.

[0016] In some embodiments of the present invention, the temperature of the enzymatic pre-gelatinization is 30°C to 55°C;

[0017] And / or, the enzymatic pre-gelatinization time is 5 min to 20 min.

[0018] In some embodiments of the present invention, in the gelatinization step, the gelatinization temperature is 70°C to 95°C;

[0019] And / or, the gelatinization time is 10 min to 60 min.

[0020] In some embodiments of the present invention, based on 100% of the total mass of the gelatinized rice milk, the added amount of the whey protein powder is 1% to 10%.

[0021] In some embodiments of the present invention, based on 100% of the total mass of the homogenized rice milk, the added amount of the composite bacteria is 0.1% to 2.5%;

[0022] And / or, the mass ratio of the yeast to the lactic acid bacteria in the composite bacteria is (1-3): (1-5).

[0023] In some embodiments of the present invention, in the fermentation step, the fermentation temperature is 25° C. to 45° C., the fermentation time is 10 h to 60 h, and the pH of the fermentation is controlled at 4.8 to 6.0.

[0024] The present invention also provides a rice milk coffee beverage prepared by the method for preparing the rice milk coffee beverage.

[0025] In some embodiments of the present invention, the rice milk coffee beverage further comprises an acid regulator and a stabilizer.

[0026] The beneficial effects that can be achieved by the present invention are:

[0027] As the main food crop in my country's daily life, rice is not only a basic source of energy, but also an important part of food culture. It has a wide consumer group and consumption base.

[0028] The present invention combines rice instead of milk and coffee, improves the problem that traditional coffee beverages are not suitable for people with lactose intolerance because of the addition of milk, and can also give coffee beverages a unique flavor. In terms of taste, the fermented rice milk obtained by pre-gelatinization and gelatinization of brown rice + glutinous rice, and then adding whey protein powder for high-pressure homogenization and fermentation has a mellow and smooth taste, can replace cow's milk, increase the thickness of coffee beverages, modify the bitterness and roughness of coffee, and at the same time, double-bacteria fermentation gives microbubbles, increasing the richness of the taste. In terms of flavor, the fermented rice milk obtained by double-bacteria fermentation has the rice aroma of brown rice and glutinous rice, and can bring special rice wine aroma and fermented milk aroma.

[0029] The present invention uses brown rice and glutinous rice as a base. Compared with polished rice, brown rice has more abundant nutrients such as protein, microorganisms, minerals, etc., and the rice bran and germ parts of brown rice are also rich in vitamin B group and vitamin E.

[0030] The invention utilizes a composite enzyme to perform enzymatic pre-gelatinization on the mixed rice slurry. The composite enzyme composed of cellulase and amylase assists the pre-gelatinization of the mixed rice slurry, which can destroy the bran layer structure and internal structure of brown rice and glutinous rice, change the starch granule structure of the mixed rice slurry, and obtain a more delicate and smooth taste.

[0031] The present invention further utilizes the combined action of lactic acid bacteria and yeast to ferment. The yeast ferments and decomposes the sugar source of rice milk to produce alcohol and carbon dioxide, which can give the rice milk coffee beverage a charming wine aroma and carbon dioxide gas, while increasing its taste and flavor. During the fermentation process, the lactic acid bacteria hydrolyze whey protein and part of the enzymatically hydrolyzed rice milk to produce easily absorbed monosaccharides and free amino acids as well as multiple vitamins, thereby enabling the rice milk coffee beverage to obtain a nutritious and rich-tasting base. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0033] Figure 1 The present invention is a schematic diagram of the preparation process of a rice milk coffee beverage.

[0034] Figure 2 This is a sensory evaluation score curve diagram of the rice milk coffee beverages of Examples 1 to 6 of the present invention.

[0035] Figure 3 This is a sensory evaluation score curve diagram of the milk coffee beverages of Examples 7 to 13 of the present invention.

[0036] Figure 4 It is a sensory evaluation score curve diagram of the milk coffee beverages of Comparative Example 1 and Examples 14 to 19 of the present invention.

[0037] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0038] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] In the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0041] The active ingredient of coffee is caffeine, which has a stimulating effect on the human stomach and intestines. Therefore, consumers usually add milk to coffee to reduce irritation to the gastric mucosa. According to literature, 65% to 75% of people in the world are lactose intolerant, and Chinese people are also a high-risk group.

[0042] As the main food crop in my country's daily life, rice is not only a basic source of energy, but also an important part of food culture. It has a wide consumer group and consumption base.

[0043] In view of this, the present invention compounds rice and coffee to develop a rice milk coffee beverage, which can replace milk to reduce the stimulation of caffeine on gastric mucosa, and at the same time can take care of people with lactose intolerance, thereby expanding the consumer group.

[0044] Reference Figure 1 The method for preparing the rice milk coffee beverage provided by the present invention comprises the following steps:

[0045] S10, mixing brown rice slurry and glutinous rice slurry to obtain mixed rice slurry;

[0046] S20, adding a composite enzyme to the mixed rice slurry for enzymatic pregelatinization to obtain pregelatinized rice slurry, wherein the composite enzyme comprises cellulase and amylase;

[0047] S30, gelatinizing the pre-gelatinized rice milk to obtain gelatinized rice milk;

[0048] S40, adding whey protein powder to the gelatinized rice milk and homogenizing to obtain homogenous rice milk;

[0049] S50, adding composite bacteria to the homogenized rice milk for fermentation to obtain fermented rice milk, wherein the composite bacteria includes yeast and lactic acid bacteria;

[0050] S60, mixing the fermented rice milk and coffee to obtain a rice milk coffee beverage.

[0051] Compared with polished rice, brown rice has more nutrients such as protein, microorganisms, and minerals. The bran and germ of brown rice are also rich in vitamin B and vitamin E, which makes coffee beverages rich in nutrients. Glutinous rice is also rich in protein and vitamins. The mixed rice milk with brown rice has a certain lubricating effect, which can alleviate the irritating effect of caffeine on the human stomach and intestines, and solves the problem that adding milk to improve the bitter and rough taste of coffee can easily cause discomfort to people with lactose intolerance.

[0052] In some embodiments, brown rice and glutinous rice may be pulped to obtain brown rice pulp and glutinous rice pulp, and then the brown rice pulp and the glutinous rice pulp may be mixed to obtain mixed rice pulp.

[0053] In some embodiments, the mixed rice slurry is filtered after pulping to improve the smooth taste of the mixed rice slurry. Adding it to coffee can improve the smooth taste of the coffee beverage, thereby alleviating the irritating effect of caffeine on the human gastrointestinal tract.

[0054] In some embodiments, the mass ratio of brown rice slurry to glutinous rice slurry is (1-4):1, which can be any ratio in the range of (1-4):1, such as 1:1, 2:1, 3:1, 4:1, etc.

[0055] In some embodiments, the brown rice slurry includes brown rice and water. The brown rice slurry can be obtained by mixing the brown rice and water and then beating the mixture. The moisture content of the brown rice slurry is 30% to 50%, which can be 30%, 35%, 40%, 45%, 50%, etc.

[0056] In some embodiments, the glutinous rice slurry includes glutinous rice and water. The glutinous rice slurry can be obtained by mixing glutinous rice and water and then beating them. The moisture content in the glutinous rice slurry is 30% to 50%, which can be 30%, 35%, 40%, 45%, 50%, etc.

[0057] In some embodiments, the moisture content in the brown rice slurry is equal to the moisture content in the glutinous rice slurry.

[0058] The nutritional value of brown rice is higher than that of glutinous rice. The bran and germ of brown rice are rich in vitamin B group and vitamin E, which can not only improve the immune function, but also promote blood circulation, help eliminate depression and irritability, and make people full of energy. At the same time, it is rich in various trace elements, such as potassium, magnesium, zinc, iron, manganese, etc. This embodiment increases the proportion of brown rice, improves the taste of the rice milk coffee beverage, and also gives the rice milk coffee beverage a better nutritional value.

[0059] In the present invention, step S20 performs enzymatic pre-gelatinization treatment on the mixed rice slurry, which can destroy the bran layer structure and internal structure of the brown rice and glutinous rice, change the starch granule structure of the mixed rice slurry, change the viscosity of the rice slurry, and make the rice slurry have a smoother taste and better fluidity. When the rice slurry and coffee are subsequently mixed to prepare a coffee beverage, it is beneficial to reduce stratification and precipitation, so that the prepared coffee beverage has a better smooth taste, thereby achieving the purpose of alleviating the irritation of caffeine to the gastric mucosa.

[0060] The present invention utilizes a composite enzyme composed of cellulase and amylase to perform enzymatic pre-gelatinization treatment on mixed rice slurry. Cellulase can destroy substances such as cellulose in the cortex of rice grains, improve the smooth taste of rice slurry, promote the dissolution of soluble dietary fiber in rice grains, and improve the nutritional value and health benefits of coffee beverages. Moreover, cellulase can improve the in vitro digestibility of starch in rice slurry, making its nutrients easy to be absorbed and digested by the human body. Amylase can hydrolyze the long-chain starch molecules in rice slurry into short-chain molecules, generating components such as dextrin and oligosaccharides that are easy for human body to digest and absorb. The gelatinization characteristics, rheological characteristics and thermodynamic properties of rice slurry treated with amylase can be improved, so that rice slurry can obtain a better mellow and smooth taste, can replace cow's milk to increase the thickness of coffee beverages, and modify the bitterness and roughness of coffee. In addition, amylase reduces the viscosity of rice slurry, and the components in rice slurry are easy to be digested and absorbed by the human body, and are also easy to be mixed with coffee to form a uniform rice milk coffee beverage, reducing the problem of precipitation and stratification in rice milk coffee beverages.

[0061] In some embodiments, based on 100% of the total mass of the mixed rice slurry, the added amount of the complex enzyme is 0.15%, which can effectively achieve the purpose of enzymatic hydrolysis of the mixed rice slurry.

[0062] In some embodiments, the mass ratio of cellulase and amylase in the composite enzyme is (1:2) to (1:8), which can be 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 2:1, 2:3, etc., which can not only effectively achieve the purpose of enzymatic hydrolysis of mixed rice slurry, but also achieve the purpose of pre-gelatinization.

[0063] In some embodiments, the temperature of enzymatic pregelatinization is 30°C to 55°C, and can be 30°C, 35°C, 40°C, 45°C, 50°C, 55°C or other temperatures within the range of 30°C to 55°C. This not only can better exert the effects of cellulase and amylase, but also can complete the pregelatinization process of the mixed rice slurry, so that the mixed rice slurry has a better smooth taste.

[0064] In some embodiments, the enzymatic pre-gelatinization time is 5 min to 20 min, and can be any value in the range of 5 min to 20 min, such as 5 min, 10 min, 15 min, 20 min, etc. Under the above enzymatic pre-gelatinization time conditions, it is beneficial to promote the enzymatic hydrolysis and pre-gelatinization of the mixed rice slurry, so that the rice slurry has a better mellow and smooth taste.

[0065] The invention further performs gelatinization after completing enzymatic pre-gelatinization, which is beneficial to further improve the gelatinization degree of the rice milk and greatly improve the mellow and smooth taste of the rice milk.

[0066] In some embodiments, the gelatinization temperature is 70°C to 95°C, and can be any value within the range of 70°C to 95°C, such as 70°C, 75°C, 80°C, 85°C, 90°C, or 95°C.

[0067] In some embodiments, the gelatinization time is 10 min to 60 min, and can be any value within the range of 10 min to 60 min, such as 10 min, 20 min, 30 min, 40 min, 50 min, 60 min, etc.

[0068] Considering that the use of a single grain to make rice milk and coffee compound will lack protein, the present invention adds whey protein powder to the gelatinized rice milk in step S40 to increase the protein content of the rice milk base, so that the final rice milk coffee beverage is more nutritious. The whey protein added by the present invention is not only easy to digest, but also contains rich β-lactoglobulin, α-lactalbumin, immunoglobulin and other multiple active ingredients, and has low fat and lactose content. In addition, whey protein powder can also provide the required nutrients for yeast and lactic acid bacteria production and breeding and fermentation and hydrolysis processes, so as to obtain fermented rice milk with better flavor and mouthfeel.

[0069] The invention is to obtain gelatinized rice milk after completing enzymatic pre-gelatinization and gelatinization processes, and then add whey protein powder to the gelatinized rice milk, so as to avoid the high temperature conditions of the enzymatic pre-gelatinization process and the gelatinization process from destroying the effective components of the whey protein powder. After adding the whey protein powder, the invention further performs a homogenization process, which can not only make the whey protein powder evenly dispersed in the gelatinized rice milk, but also further improve the delicate and smooth taste of the rice milk.

[0070] In some embodiments, based on 100% of the total mass of gelatinized rice milk, the added amount of whey protein powder is 1% to 10%, which can be any value in the range of 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc. It can provide rich protein, give the rice milk a softer and smoother taste, and is easy to mix evenly with coffee, thereby improving the delicate and smooth taste of coffee beverages. It can also provide the required nutrients for the production of yeast and lactic acid bacteria, thereby obtaining fermented rice milk with better flavor and taste and richer texture.

[0071] The invention performs enzymatic pre-gelatinization, gelatinization, and homogenization on the mixed rice slurry, so that nutrients such as protein, vitamins, minerals, etc. in the rice slurry are dissolved, and the rice slurry is made into a uniform system after gelatinization, hydration, and homogenization. At this time, fermentation treatment is performed, so that various nutrients in the rice slurry can be effectively utilized, and the uniform system is also conducive to fermentation.

[0072] The present invention adds composite bacteria in the fermentation step, and the composite bacteria includes yeast and lactic acid bacteria. The yeast can promote the rice milk to produce alcohol and carbon dioxide, so that the rice milk obtains a unique sour taste and wine aroma. Moreover, the yeast can also participate in the production of aroma substances such as ethyl acetate, β-phenylethanol, isopentanol, etc. in the fermentation system, so that the rice milk becomes porous and fluffy and obtains a unique flavor, which can effectively improve the taste and flavor of coffee beverages. In addition, the yeast can hydrolyze the protein in the rice milk into free amino acids, improve the nutritional value of the rice milk, and also provide an energy source for the fermentation of lactic acid bacteria. Lactic acid bacteria can convert glucose and fructose into lactic acid through metabolic activities during the fermentation process, so that the pH of the rice milk decreases, thereby effectively inhibiting the growth of harmful microorganisms and extending the shelf life of food. Moreover, during the fermentation process, lactic acid will produce some active substances such as lactic acid and lactobacillus, which not only have antibacterial and antioxidant functions, and can improve the quality and nutritional value of food, but also can improve the viscosity, hydrophilic effect and rheological characteristics of rice milk, thereby giving the rice milk a smooth and delicate taste. The subsequent compounding with coffee to prepare rice milk coffee beverage can effectively improve the bitterness and roughness of coffee.

[0073] In some embodiments, based on the total mass of homogenized rice slurry being 100%, the added amount of the composite bacteria is 0.1% to 2.5%, which can be any value in the range of 0.1% to 2.5%, such as 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, etc. In this way, a better fermentation effect can be achieved, giving the rice milk coffee beverage a unique flavor, while also improving the delicate and smooth taste of the rice milk coffee beverage and reducing the irritation of caffeine to the gastric mucosa.

[0074] In some embodiments, the mass ratio of yeast to lactic acid bacteria in the composite bacteria is (1-3): (1-5), which can be 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 2:1, 2:3, 3:5, 3:4, etc.

[0075] In some embodiments, in the fermentation step, the fermentation temperature is 38° C., the fermentation time is 10 h to 60 h, and the fermentation pH is controlled at 4.8 to 6.0, which is beneficial to improving the fermentation effect of yeast and lactic acid bacteria and obtaining rice milk with a smooth and soft taste.

[0076] Mixing the fermented rice milk and coffee can obtain a rice milk coffee beverage with rice milk as the base, which can give the rice milk coffee beverage a delicate and smooth taste and a unique flavor. It can also replace milk to improve the bitterness and roughness of coffee, expanding the consumer base to people with lactose intolerance.

[0077] In the present invention, coffee can be prepared into liquid first, and the liquid coffee and fermented rice milk are evenly mixed to obtain the rice milk coffee beverage, or powdered coffee powder can be added to the fermented rice milk to obtain the rice milk coffee beverage.

[0078] The present invention does not limit the mass ratio of coffee and fermented rice milk, and the coffee and fermented rice milk can be mixed arbitrarily according to the needs of consumers.

[0079] In the present invention, common materials in the food field can be added to the rice milk coffee beverage as needed. In some embodiments, the rice milk coffee beverage also includes an acid regulator and a stabilizer. The acid regulator can adjust the taste of the coffee beverage, and the stabilizer can improve the stability of the coffee beverage to prevent problems such as stratification and precipitation.

[0080] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that the following specific embodiments are only used to explain the present invention, and are not used to limit the present invention.

[0081] Example 1 to Example 6

[0082] Example 1 to Example 6 The preparation of rice milk coffee beverage comprises the following steps:

[0083] S10, mixing brown rice slurry and glutinous rice slurry to obtain mixed rice slurry, the mass ratio of brown rice to glutinous rice is 2.5:1; the moisture content in the brown rice slurry is 40%, and the moisture content in the glutinous rice slurry is 50%.

[0084] S20, adding 0.15% of the mass of the mixed rice slurry of the composite enzyme to the mixed rice slurry for enzymatic hydrolysis and pregelatinization, the enzymatic hydrolysis and pregelatinization temperature is 40° C., and the enzymatic hydrolysis and gelatinization time is controlled at 10 min to obtain pregelatinized rice slurry, the composite enzyme includes cellulase and amylase, and the mass ratio of cellulase to amylase is 1:1.

[0085] S30, gelatinizing the pre-gelatinized rice milk of step S20, wherein the gelatinization temperature is 85° C. and the gelatinization time is 40 min to obtain gelatinized rice milk;

[0086] S40, adding 5% whey protein powder of the mass of gelatinized rice milk to the gelatinized rice milk for hydration and homogenizing to obtain homogenized rice milk;

[0087] S50, adding 1% of the mass of the composite bacteria to the homogeneous rice slurry for fermentation to obtain fermented rice milk, the fermentation temperature is 38° C., the fermentation time is 10 h to 60 h, the composite bacteria are yeast and lactic acid bacteria, and the mass ratio of the yeast to the lactic acid bacteria is 1:1.

[0088] S60, mixing the fermented rice milk and coffee to obtain a rice milk coffee beverage.

[0089] Among them, the specific fermentation times of Example 1 to Example 6 are 10h, 20h, 30h, 40h, 50h, and 60h, respectively.

[0090] According to Table 1, sensory evaluation was performed on 6 groups of rice milk coffee beverages from Example 1 to Example 6. The scores are shown in Tables 2 and Figure 2 ,Depend on Figure 2 It can be seen that as the fermentation time increases from 10h to 40h, the score of the rice milk coffee beverage gradually increases, and reaches the highest score at 40h in Example 5, which shows that the fermentation time affects the quality and taste of the rice milk coffee beverage. In addition, the rice milk coffee beverages of Examples 4 to 6 all received high scores in color, aroma, and taste, making the coffee beverage milky white, white or gray, transparent, and having rice and wine aromas, harmonious aromas, no peculiar smell, and smooth taste, moderate sweetness and sourness, which can improve the bitterness and roughness of coffee.

[0091] Example 7 to Example 13

[0092] Example 7 to Example 13 The preparation of rice milk coffee beverage comprises the following steps:

[0093] S10, mixing brown rice slurry and glutinous rice slurry to obtain mixed rice slurry, the mass ratio of brown rice to glutinous rice is (1-4):1, the moisture content in the brown rice slurry is 50%, and the moisture content in the glutinous rice slurry is 50%;

[0094] S20, adding 0.15% of the mass of the mixed rice slurry of the composite enzyme to the mixed rice slurry for enzymatic hydrolysis and pregelatinization, the enzymatic hydrolysis and pregelatinization temperature is 42° C., and the enzymatic hydrolysis and gelatinization time is controlled at 10 min to obtain pregelatinized rice slurry, the composite enzyme includes cellulase and amylase, and the mass ratio of cellulase to amylase is 1:1.

[0095] S30, gelatinizing the pre-gelatinized rice milk of step S20, wherein the gelatinization temperature is 85° C. and the gelatinization time is 40 min to obtain gelatinized rice milk;

[0096] S40, adding 5% whey protein powder of the mass of gelatinized rice milk to the gelatinized rice milk for hydration and homogenizing to obtain homogenized rice milk;

[0097] S50, adding 1% of the mass of the composite bacteria to the homogeneous rice slurry for fermentation to obtain fermented rice milk, the fermentation temperature is 37° C., the fermentation time is 40 h, the composite bacteria are yeast and lactic acid bacteria, and the mass ratio of yeast to lactic acid bacteria is 3:2.

[0098] S60, mixing the fermented rice milk and coffee to obtain a rice milk coffee beverage.

[0099] The mass ratios of the brown rice paste and the glutinous rice paste in Examples 7 to 13 are specifically 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, and 4:1.

[0100] According to Table 1, a total of 7 groups of rice milk coffee beverages from Example 7 to Example 13 were subjected to sensory evaluation, and the scores are shown in Tables 2 and Figure 3 ,Depend on Figure 3 It can be seen that as the mass ratio of brown rice slurry to glutinous rice slurry increases, the quality and taste of the rice milk coffee beverage gradually increase, and a better quality and taste are obtained at 2.5:1 in Example 10. In addition, the rice milk coffee beverages of Examples 7, 8, 9, 11, 12, and 13 all obtained higher scores in color, aroma, and taste, making the coffee beverage taste smooth in the taste scoring project, with a certain sourness and sweetness, and can improve the bitterness and roughness of coffee.

[0101] Examples 14 to 19 and Comparative Example 1

[0102] Example 14 to Example 19 The preparation of the rice milk coffee beverage comprises the following steps:

[0103] S10, mixing brown rice slurry and glutinous rice slurry to obtain mixed rice slurry, the mass ratio of brown rice to glutinous rice is 2.5:1, the moisture content in the brown rice slurry is 30%, and the moisture content in the glutinous rice slurry is 40%;

[0104] S20, adding 0.15% of the mass of the mixed rice slurry composite enzyme to the mixed rice slurry for enzymatic pregelatinization, the enzymatic pregelatinization temperature is 41° C., and the enzymatic gelatinization time is controlled at 20 min to obtain pregelatinized rice slurry, the composite enzyme includes cellulase and amylase, and the mass ratio of cellulase to amylase is 1:1.

[0105] S30, gelatinizing the pre-gelatinized rice milk of step S20, wherein the gelatinization temperature is 85° C. and the gelatinization time is 40 min to obtain gelatinized rice milk;

[0106] S40, adding 5% whey protein powder of the mass of gelatinized rice milk to the gelatinized rice milk for hydration and homogenizing to obtain homogenized rice milk;

[0107] S50, adding composite bacteria to the homogenized rice milk for fermentation to obtain fermented rice milk, the fermentation temperature is 38° C., the fermentation time is 40 h, the composite bacteria are yeast and lactic acid bacteria, and the mass ratio of yeast to lactic acid bacteria is 2:3.

[0108] S60, mixing the fermented rice milk and coffee to obtain a rice milk coffee beverage.

[0109] Comparative Example 1: Rice milk coffee was prepared with reference to the preparation method of Examples 14 to 19, except that, based on 100% of the total mass of the homogenized rice slurry, the inoculation amount of the composite bacteria in Comparative Example 1 and Examples 14 to 19 was specifically 0, 0.4%, 0.7%, 1.25%, 1.6%, 2%, and 2.4%.

[0110] According to Table 1, a total of 7 groups of rice milk coffee beverages from Example 14 to Example 19 and Comparative Example 1 were subjected to sensory evaluation, and the scores are shown in Tables 2 and Figure 4 ,Depend on Figure 4 It can be seen that in Comparative Example 1, no composite bacteria were added, and its sensory score was only 76, which was relatively low. In Examples 14 to 19, 0.4%, 0.7%, 1.25%, 1.6%, 2%, and 2.4% were gradually added for fermentation treatment, which effectively improved the quality of the rice milk coffee beverage, and a better quality was obtained when the addition amount was 2% in Example 18. In addition, Examples 17, 18, and 19 all obtained high scores in color, aroma, and taste, making the coffee beverage smooth in the taste scoring project, with a certain sourness and sweetness, and can improve the bitterness and roughness of coffee.

[0111] Table 1 Sensory evaluation scoring criteria

[0112]

[0113] Table 2 Sensory evaluation results

[0114]

[0115]

[0116] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for preparing a rice milk coffee beverage, characterized in that: The following steps are involved: Mixing brown rice slurry and glutinous rice slurry to obtain mixed rice slurry; Adding a composite enzyme to the mixed rice milk for enzymatic pre-gelatinization to obtain pre-gelatinized rice milk, wherein the composite enzyme comprises cellulase and amylase; The pre-gelatinized rice milk is gelatinized to obtain gelatinized rice milk; adding whey protein powder to the gelatinized rice milk and performing homogenization to obtain homogenized rice milk; Adding composite bacteria to the homogenized rice milk for fermentation to obtain fermented rice milk, wherein the composite bacteria includes yeast and lactic acid bacteria; The fermented rice milk and coffee are mixed to obtain a rice milk coffee beverage.

2. The method for preparing the rice milk coffee beverage according to claim 1, characterized in that: The mass ratio of the brown rice paste to the glutinous rice paste is (1-4):

1.

3. The method for preparing the rice milk coffee beverage according to claim 1, characterized in that: The mass ratio of cellulase to amylase in the complex enzyme is (1:2) to (1:8); And / or, based on 100% of the total mass of the mixed rice milk, the added amount of the complex enzyme is 0.05% to 0.3%.

4. The method for preparing the rice milk coffee beverage according to claim 1, characterized in that: The temperature of the enzymatic pre-gelatinization is 30°C to 55°C; And / or, the enzymatic pre-gelatinization time is 5 min to 20 min.

5. The method for preparing the rice milk coffee beverage according to claim 1, characterized in that: In the gelatinization step, the gelatinization temperature is 70°C to 95°C; And / or, the gelatinization time is 10 min to 60 min.

6. The method for preparing the rice milk coffee beverage according to claim 1, characterized in that: Based on 100% of the total mass of the gelatinized rice milk, the added amount of the whey protein powder is 1% to 10%.

7. The method for preparing the rice milk coffee beverage according to claim 1, characterized in that: Based on 100% of the total mass of the homogenized rice milk, the added amount of the composite bacteria is 0.1% to 2.5%; And / or, the mass ratio of the yeast to the lactic acid bacteria in the composite bacteria is (1-3): (1-5).

8. The method for preparing the rice milk coffee beverage according to claim 1, characterized in that: In the fermentation step, the fermentation temperature is 25° C. to 45° C., the fermentation time is 10 h to 60 h, and the fermentation pH is controlled at 4.8 to 6.

0.

9. A rice milk coffee beverage prepared by the method for preparing a rice milk coffee beverage according to any one of claims 1 to 8.

10. The rice milk coffee beverage according to claim 9, characterized in that: The rice milk coffee beverage also includes an acid regulator and a stabilizer.

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