Bacterial enzyme compound microbial agent product for fermenting fruit and vegetable juice and preparation method of bacterial enzyme compound microbial agent product

Abstract

The invention belongs to the technical field of fruit and vegetable juice fermentation preparations, and particularly relates to a bacterium enzyme compound microbial agent product for fruit and vegetable juice fermentation and a preparation method thereof. Comprising a bacterial preparation and an enzyme preparation, the bacterial preparation is composed of lactobacillus plantarum, lactobacillus casei, lactobacillus paracasei and lactobacillus mucus fermentation, the enzyme preparation is composed of pectinase, hemicellulase and cellulase, and the bacterial preparation and the enzyme preparation are co-cultured to prepare the bacterial enzyme composite microbial agent. The bacterium-enzyme composite microbial agent is prepared in a bacterium-enzyme co-culture mode, and fruit and vegetable cell walls are decomposed when the bacterium-enzyme composite microbial agent is used, so that more functional components in fruit and vegetable cells are released, and the digestibility and functionality of fruit and vegetable juice are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of fruit and vegetable juice fermentation preparations, and in particular relates to a bacterial enzyme composite microbial inoculant product for fruit and vegetable juice fermentation and a preparation method thereof. Background Art

[0002] my country has a huge output of fruits and vegetables. In addition to meeting people's normal edible needs, further processing of fruits and vegetables is also one of the important uses of fruit and vegetable products. In addition to retaining the nutrients of fruits and vegetables themselves, fruit and vegetable juice products also have the characteristics of being easy to carry and easy to store. Fruit and vegetable juice fermentation products are products obtained by further fermentation and processing of fruit and vegetable juice. Through the fermentation of probiotics such as lactic acid bacteria, organic acids and other substances are produced, thereby inhibiting the growth of spoilage bacteria and pathogenic bacteria, extending the shelf life, improving the taste and flavor of fruit and vegetable juice, and improving the human intestinal environment through probiotics. At present, most microbial preparations used for fruit and vegetable juice fermentation are lactic acid bacteria, and their substrates are sugars in fruits and vegetables. The functional components in fruit and vegetable cells are not completely released, such as saponins, polyphenols, etc. This is because the ability of lactic acid bacteria to decompose the cell walls of fruits and vegetables is limited, which limits the release of functional components and requires further decomposition of the cell walls. Summary of the invention

[0003] The object of the present invention is to provide a composite microbial agent product for fruit and vegetable juice fermentation and a preparation method thereof, so as to solve the problems existing in the prior art.

[0004] The technical solution adopted by the present invention to solve its technical problem is:

[0005] A bacterial enzyme composite microbial agent product for fruit and vegetable juice fermentation comprises a bacterial preparation and an enzyme preparation. The bacterial preparation is composed of Lactobacillus plantarum, Lactobacillus casei, Lactobacillus paracasei and Lactobacillus mucosa fermentation, and the enzyme preparation is composed of pectinase, hemicellulase and cellulase. The bacterial preparation and the enzyme preparation are prepared into a bacterial enzyme composite microbial agent through co-cultivation.

[0006] A method for preparing a bacterial enzyme composite microbial agent product for fruit and vegetable juice fermentation comprises the following steps:

[0007] (1) Preparation of solid culture medium and liquid culture medium;

[0008] (2) inoculating plant lactobacillus, Lactobacillus casei, Lactobacillus paracasei, and fermented mucus lactobacillus into solid culture medium for activation culture to obtain bacterial suspensions of plant lactobacillus, Lactobacillus casei, Lactobacillus paracasei, and fermented mucus lactobacillus, and mixing the bacterial suspensions of plant lactobacillus, Lactobacillus casei, Lactobacillus paracasei, and fermented mucus lactobacillus to obtain a bacterial preparation;

[0009] (3) mixing pectinase, hemicellulase and cellulase to obtain an enzyme preparation, adding the bacterial preparation and the enzyme preparation to a liquid culture medium for co-cultivation to obtain a mixed culture solution;

[0010] (4) The mixed culture solution is filtered, concentrated and washed through an ultrafiltration membrane to obtain a bacterial enzyme composite microbial agent.

[0011] Furthermore, the formula of the solid culture medium in step (1) is: 20 g / L peptone, 10 g / L yeast powder, 5 g / L sodium acetate, 5 g / L potassium dihydrogen phosphate, 4 g / L dipotassium hydrogen phosphate, 1 mL Tween-80, 10.0 g / L calcium carbonate, 15.0 g / L agar, and 10 g / L sucrose. After preparation, the solid culture medium is diluted to volume with pure water and the pH is adjusted to 6.8.

[0012] Furthermore, the formula of the liquid culture medium in step (1) is: 20 g / L peptone, 10 g / L yeast powder, 5 g / L sodium acetate, 5 g / L potassium dihydrogen phosphate, 4 g / L dipotassium hydrogen phosphate, 1 mL Tween-80, 5 g / L sucrose, and 5 g / L polydextrose. After preparation, the liquid culture medium is diluted to volume with pure water and the pH is adjusted to 6.8.

[0013] Furthermore, in step (2), the bacterial suspensions of Lactobacillus plantarum, Lactobacillus casei, Lactobacillus paracasei, and Lactobacillus mucosa fermentation are mixed at a dry matter weight ratio of 2:1:1:1.

[0014] Furthermore, in step (3), the mass ratio of pectinase, hemicellulase and cellulase mixed is 3:(2-4):(2-4).

[0015] Furthermore, in step (3), the mass ratio of the dry matter of the bacterial preparation to the mass ratio of the enzyme preparation is (5-8):1.

[0016] The present invention has the following beneficial effects:

[0017] 1. The present invention prepares a bacterial enzyme composite microbial agent by co-culturing bacteria and enzymes, which decomposes the cell walls of fruits and vegetables during use, thereby releasing more functional components in the fruit and vegetable cells, thereby increasing the digestibility and functionality of the fruit and vegetable juice.

[0018] 2. Adding fermented mucus lactobacillus to bacterial preparations can give fruit and vegetable juice a certain alcohol-resolving effect.

[0019] 3. The bacterial preparations and enzyme preparations in the bacterial-enzyme composite microbial agent can synergistically ferment in fruit and vegetable fermentation, improve fermentation efficiency and shorten fermentation time. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the process flow of the present invention.

[0021] Figure 2 It is a schematic diagram of the change trend of total acid and pH during the fermentation process of Comparative Example 1 of the present invention.

[0022] Figure 3 It is a schematic diagram of the change trend of total sugar during the fermentation process of Comparative Example 1 of the present invention.

[0023] Figure 4 It is a schematic diagram of the change trend of total acid and pH during the fermentation process of Example 5 of the present invention.

[0024] Figure 5 This is a schematic diagram of the change trend of total sugar during the fermentation process of Example 5 of the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and drawings. 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.

[0026] Embodiment 1:

[0027] A bacterial enzyme composite microbial agent product for fruit and vegetable juice fermentation comprises a bacterial preparation and an enzyme preparation. The bacterial preparation is composed of Lactobacillus plantarum, Lactobacillus casei, Lactobacillus paracasei and Lactobacillus mucosa fermentation, and the enzyme preparation is composed of pectinase, hemicellulase and cellulase. The bacterial preparation and the enzyme preparation are prepared into a bacterial enzyme composite microbial agent through co-cultivation.

[0028] The plant lactobacillus, casei lactobacillus, paracasei lactobacillus and fermented mucus lactobacillus in the bacterial preparation are all commercially available products, which are all lactic acid bacteria and belong to probiotics. The combination of plant lactobacillus, casei lactobacillus and paracasei lactobacillus can enhance the free radical scavenging activity of DPPH, ABTS and FRAP in fruit and vegetable juices, and can enhance the fragrance of fruit and vegetable juices. The action on the human body is beneficial to maintaining the balance of flora in the human intestine, and has the effects of relieving lactose intolerance. Fermented mucus lactobacillus has good acidophilus properties and can adapt to fruit and vegetable juices with high acidic components such as apples. At the same time, fermented mucus lactobacillus is also effective in sobering up, and can reduce the concentration of ethanol and acetaldehyde in serum, thereby relieving the discomfort caused by drunkenness. Fermented mucus lactobacillus can also reduce liver damage caused by acute drinking, by reducing serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, and reducing the expression of liver cytochrome P4502E1, thereby helping to protect the liver from alcohol damage.

[0029] Pectinase, hemicellulase and cellulase in the enzyme preparation are all commercially available enzyme preparations. Pectinase, hemicellulase, cellulase and β-glucanase are used to decompose the cell walls of fruits and vegetables, so that some polysaccharides in the cell walls of fruits and vegetables are decomposed into monosaccharides. The presence of polysaccharides will make the viscosity of the fermented fruit and vegetable juice larger, and the monosaccharides such as glucose and fructose produced after the decomposition of polysaccharides can be directly used by fungi, which reduces the time for fungi to decompose polysaccharides, thereby improving the fermentation efficiency and contributing to the proliferation of fungi. After the polysaccharides are decomposed into monosaccharides, it is also beneficial to reduce the viscosity of the fruit and vegetable juice. This bacterial enzyme synergistic fermentation method can make the degradation of macromolecular sugar substances more thorough, and the fermentation efficiency is higher, which is better than the efficiency of using bacteria alone. Residual monosaccharides such as glucose can be directly absorbed by the human body. Although monosaccharides such as xylose and arabinose cannot be absorbed by the human body, xylose, arabinose, etc. are functional sugars, which are beneficial for regulating the intestinal environment of the human body, and arabinose also has the effect of sobering up, which can increase the activity of acetaldehyde dehydrogenase and alcohol dehydrogenase in the human body. These two enzymes play a key role in the metabolism of alcohol, acetaldehyde dehydrogenase is responsible for converting acetaldehyde into acetic acid, while alcohol dehydrogenase is responsible for converting ethanol into acetaldehyde. Therefore, arabinose accelerates the metabolism of alcohol in the body by increasing the activity of these two enzymes.

[0030] Therefore, the bacterial enzyme composite microbial agent product of the present invention has a high fermentation efficiency when used for fruit and vegetable juice fermentation, and reduces the viscosity of the fruit and vegetable juice, and is suitable for filtering and clarifying when producing non-live bacteria type fruit and vegetable juice. In addition, the fermented mucus lactobacillus used can relieve the discomfort caused by drunkenness, and can give the fruit and vegetable juice a certain hangover-relieving effect when producing live bacteria type fruit and vegetable juice. If some arabinose is added to the fermented fruit and vegetable juice, the hangover-relieving effect of the fruit and vegetable juice can be further improved.

[0031] Embodiment 2:

[0032] like Figure 1 As shown, a method for preparing a bacterial enzyme composite microbial agent product for fruit and vegetable juice fermentation comprises the following steps:

[0033] (1) Prepare solid culture medium and liquid culture medium.

[0034] The formula of solid culture medium is: peptone 20g / L, yeast powder 10g / L, sodium acetate 5g / L, potassium dihydrogen phosphate 5g / L, dipotassium hydrogen phosphate 4g / L, 1mL Tween-80, calcium carbonate 10.0g / L, agar 15.0g / L, sucrose 10g / L. After preparation, dilute to volume with pure water and adjust the pH to 6.8.

[0035] The formula of the liquid culture medium is: peptone 20g / L, yeast powder 10g / L, sodium acetate 5g / L, potassium dihydrogen phosphate 5g / L, dipotassium hydrogen phosphate 4g / L, 1mL Tween-80, sucrose 5g / L, polydextrose 5g / L. After preparation, dilute to volume with pure water and adjust the pH to 6.8.

[0036] (2) Lactobacillus plantarum, Lactobacillus casei, Lactobacillus paracasei, and Lactobacillus fermentans are inoculated into solid culture medium for activation culture to obtain bacterial suspensions of Lactobacillus plantarum, Lactobacillus casei, Lactobacillus paracasei, and Lactobacillus fermentans. Specifically:

[0037] The solid culture medium is prepared into 20 slant culture mediums and 20 plate culture mediums, the strains of Lactobacillus plantarum are inoculated on the slant culture medium, cultured at 37°C for 36h, 5 strains with growth advantage are taken, the bacterial lawn is washed with sterile saline, the washed bacterial lawn is evenly coated on 20 plate culture mediums, cultured at 37°C for 36h, and the colonies with large colony morphology and good growth are picked and evenly shaken in sterile saline to obtain a bacterial suspension of Lactobacillus plantarum. The preparation method of the bacterial suspension of Lactobacillus casei, Lactobacillus paracasei, and fermented mucus lactobacillus is the same as the preparation method of the bacterial suspension of Lactobacillus plantarum, so as to obtain the bacterial suspension of Lactobacillus plantarum, Lactobacillus casei, Lactobacillus paracasei, and fermented mucus lactobacillus.

[0038] Bacterial suspensions of Lactobacillus plantarum, Lactobacillus casei, Lactobacillus paracasei and Lactobacillus mucosa fermentation were mixed in a dry matter weight ratio of 2:1:1:1 to obtain a bacterial preparation, and the bacterial preparation was added into a liquid culture medium.

[0039] (3) Pectinase, hemicellulase and cellulase were mixed in a mass ratio of 3:2:2 to obtain an enzyme preparation, and the enzyme preparation was added to a liquid culture medium for co-culture at 37° C. for 36 h to obtain a mixed culture solution.

[0040] During the co-cultivation process, the bacterial preparation is selective for the substrate, usually giving priority to the use of substances such as glucose in monosaccharides, then using polysaccharides to decompose them into monosaccharides, and finally using monosaccharides such as xylose. The process is relatively complicated. In general, monosaccharides such as glucose and fructose are the preferred carbon sources. The carbon sources in the liquid culture medium are sucrose and polyglucose. Sucrose is a disaccharide and polyglucose is a polysaccharide. Therefore, fungi give priority to using sucrose, decomposing it into glucose and fructose, and then further producing organic acids. In this process, the enzyme preparation decomposes polyglucose and decomposes it into glucose. If the glucose content increases, the substrate inhibition effect will appear, reducing the enzymatic reaction rate. However, due to the presence of the bacterial preparation, glucose is preferentially used by the bacterial preparation, thereby reducing the substrate of the enzymatic reaction and accelerating the enzymatic reaction rate; at the same time, the monosaccharides continuously produced by the enzymatic reaction of the enzyme preparation also provide a carbon source for the bacterial preparation to be used preferentially, so that the bacterial preparation and the enzyme preparation cooperate with each other during the cultivation process. After the enzyme preparation and the bacterial preparation are co-cultivated, the enzyme and the bacteria are naturally close, and the obtained bacterial enzyme composite microbial agent has high activity.

[0041] (4) The mixed culture solution is filtered, concentrated and washed through an ultrafiltration membrane to obtain a bacterial enzyme composite microbial agent. Ultrafiltration membrane filtration of enzymes and bacteria is a commonly used technical means. The use of an ultrafiltration membrane with a molecular weight cutoff of 10,000 Da can intercept enzymes and bacteria, and small molecular impurities and water can pass through, thereby achieving the purpose of filtering and concentration. After concentration, pure water is continuously pumped in to remove the small molecular impurities remaining in the intercepted species, thereby achieving the purpose of washing. When the bacterial enzyme composite microbial agent obtained by co-cultivation is used for the fermentation of fruit and vegetable juice, the synergistic effect of the bacterial enzyme can be continued, thereby improving the fermentation efficiency of the fruit and vegetable juice.

[0042] Embodiment 3:

[0043] This embodiment provides a method for preparing a bacterial enzyme composite microbial agent product for fruit and vegetable juice fermentation. The method steps are basically the same as those in Example 2, except that:

[0044] The mass ratio of pectinase, hemicellulase and cellulase in the enzyme preparation in step (3) is 3:4:4.

[0045] In step (3), the mass ratio of the bacterial preparation to the enzyme preparation is 8:1.

[0046] Embodiment 4:

[0047] This embodiment provides a method for preparing a bacterial enzyme composite microbial agent product for fruit and vegetable juice fermentation. The method steps are basically the same as those in Example 2, except that:

[0048] In step (3), the mass ratio of pectinase, hemicellulase and cellulase in the enzyme preparation is 3:3:3.

[0049] In step (3), the mass ratio of the bacterial preparation to the enzyme preparation is 6:1.

[0050] Comparative Example 1:

[0051] This comparative example is a production process of fruit and vegetable juice in the prior art. Mature and non-moldy apples are selected, washed, peeled, cored, cut, etc., and then pre-cooked, pulped, and juiced. Apple seeds, stigmas, etc. are filtered out to obtain the original juice. Flavoring agents, stabilizers, water, white sugar, and other raw materials and auxiliary materials are added to the original juice to make its refractive index about 12%, and the mixed juice is sterilized and set aside.

[0052] The activated lactobacillus was added into the mixed juice at a ratio of 3%, and fermentation was started at 37°C. During the fermentation process, the total sugar, total acid and other indicators were tested.

[0053] like Figure 2-3 As shown in the figure, the total acid content increased overall during the fermentation process, while the pH value and total sugar decreased overall, and the total fermentation time was 44h. The change trend of total acid and pH was relatively gentle in the early stage of fermentation, and the change amplitude intensified in the middle stage of fermentation, and then began to slow down at the end of fermentation. In the early and middle stages of fermentation, the carbon source was mainly the free sugars in the mixed juice, and it was also accompanied by the decomposition of hemicellulose and polysaccharides by the enzymes of the bacteria itself. Therefore, the total sugar decreased slowly in the early and middle stages of fermentation and slowed down in the late stage of fermentation. At the end of fermentation, the free sugars have been consumed in large quantities, and the fungi mainly use the sugars in the cells as carbon sources. This process requires the destruction of cell walls and the decomposition of polysaccharides, so the acid production process slows down.

[0054] Embodiment 5:

[0055] This embodiment is a specific application of the bacterial enzyme composite microbial agent in fruit and vegetable juice fermentation. The bacterial enzyme composite microbial agent is prepared according to Example 1, and the raw material is the mixed juice in Comparative Example 1.

[0056] The bacterial enzyme compound microbial agent was added into the mixed juice at a ratio of 3%, and fermentation was started at 37°C. During the fermentation process, indicators such as total sugar and total acid were tested.

[0057] like Figure 4-5As shown, the total acid content increased as a whole during the fermentation process, while the pH value and total sugar decreased as a whole, and the total fermentation time was 36 hours. The total acid and pH of this embodiment during the entire fermentation process changed significantly compared to those of Comparative Example 1, indicating that the amount of acid produced per unit time was relatively large. The change trend of total sugar was quite different from that of Comparative Example 1. Although it showed a downward trend as a whole, the downward trend of total sugar was relatively gentle in the early stage of fermentation, indicating that under the action of the enzyme preparation, hemicellulose and polysaccharides were continuously enzymatically hydrolyzed, and at this time the number of fungi was small, and the demand for sugar was relatively small, so the change range of the total sugar content tended to be stable. When the number of fungi increased, the demand for sugar increased, and the total sugar content decreased rapidly. At the end of the fermentation, because the enzyme destroyed the cell wall in advance, the intracellular sugars were released and consumed, and the number of remaining cells was small, so the total sugar content was low. Comparison Figure 3 and Figure 5 It can be seen that the total sugar tailing of this embodiment is small, and the total sugar at the end of fermentation is about 3.7%, while the total sugar tailing of Comparative Example 1 is more serious, and the total sugar at the end of fermentation is about 4.6%. This is because Comparative Example 1 needs to first decompose hemicellulose, polysaccharides and other substances to generate monosaccharides at the end of fermentation, and then produce acid through monosaccharides, which greatly prolongs the fermentation time. When producing non-viable fruit and vegetable juice, if the fermentation is terminated in advance in order to save fermentation time, it needs to be filtered and clarified after fermentation is completed, then the unfermented cells are filtered out, resulting in a reduction in nutrients. Therefore, in order to save fermentation time, the nutrients can only be released in the shortest possible time.

[0058] Table 1 below shows the test results of some indicators of fermented apple juice:

[0059] Table 1: Some indicators of fermented apple juice

[0060] Comparative Example 1 Example 5 Total phenols (mg / L) 95.6 114.3 Total flavonoids (mg / L) 68.1 82.7 DPPH clearance rate (%) 64.5 72.3

[0061] Functional components such as total phenols will be decomposed into smaller molecules by fungi, and their content will first increase and then decrease during the fermentation process, that is, it will decrease as the fermentation time increases. The change mechanism of total flavonoids has not been reported in detail, but its change trend is similar to that of total phenols. The DPPH clearance rate is positively correlated with the total phenol content. The higher the total phenol, the better the antioxidant activity. It can be seen from Table 1 above that the total phenol, total flavonoids and DPPH clearance rates of the fermented apple juice obtained in Example 5 are all improved. This is because the fermentation time of Example 5 is short, so the total phenol and total flavonoid contents are high, and the DPPH clearance rate is also higher. In addition, the presence of enzyme preparations causes more cells to be destroyed and more intracellular substances to be released.

[0062] The above-described embodiments are merely descriptions of preferred implementations of the present invention, and are not intended to limit the concept and scope of the present invention. Without departing from the design concept of the present invention, various modifications and improvements made by ordinary persons in the art to the technical solution of the present invention should all fall within the scope of protection of the present invention.

[0063] The techniques, shapes, and structural parts not described in detail in the present invention are all well-known techniques.

Claims

1. A bacterial enzyme composite microbial agent product for fruit and vegetable juice fermentation, characterized in that: The invention comprises a bacterial preparation and an enzyme preparation. The bacterial preparation is composed of plant lactobacillus, casei lactobacillus, paracasei lactobacillus and fermented mucus lactobacillus; the enzyme preparation is composed of pectinase, hemicellulase and cellulase. The bacterial preparation and the enzyme preparation are prepared into a bacterial-enzyme composite microbial agent by co-culturing.

2. The method for preparing a bacterial enzyme composite microbial agent product for fruit and vegetable juice fermentation according to claim 1, characterized in that: The following steps are involved: (1) Preparation of solid culture medium and liquid culture medium; (2) inoculating plant lactobacillus, Lactobacillus casei, Lactobacillus paracasei, and fermented mucus lactobacillus into solid culture medium for activation culture to obtain bacterial suspensions of plant lactobacillus, Lactobacillus casei, Lactobacillus paracasei, and fermented mucus lactobacillus, and mixing the bacterial suspensions of plant lactobacillus, Lactobacillus casei, Lactobacillus paracasei, and fermented mucus lactobacillus to obtain a bacterial preparation; (3) mixing pectinase, hemicellulase and cellulase to obtain an enzyme preparation, adding the bacterial preparation and the enzyme preparation to a liquid culture medium for co-cultivation to obtain a mixed culture solution; (4) The mixed culture solution is filtered, concentrated and washed through an ultrafiltration membrane to obtain a bacterial enzyme composite microbial agent.

3. The method for preparing the bacterial enzyme composite microbial agent product for fruit and vegetable juice fermentation according to claim 2, characterized in that: The formula of the solid culture medium in step (1) is: 20 g / L peptone, 10 g / L yeast powder, 5 g / L sodium acetate, 5 g / L potassium dihydrogen phosphate, 4 g / L dipotassium hydrogen phosphate, 1 mL Tween-80, 10.0 g / L calcium carbonate, 15.0 g / L agar, and 10 g / L sucrose. After preparation, the volume is fixed with pure water, and the pH is adjusted to 6.

8.

4. The method for preparing the bacterial enzyme composite microbial agent product for fruit and vegetable juice fermentation according to claim 2, characterized in that: The formula of the liquid culture medium in step (1) is: 20 g / L peptone, 10 g / L yeast powder, 5 g / L sodium acetate, 5 g / L potassium dihydrogen phosphate, 4 g / L dipotassium hydrogen phosphate, 1 mL Tween-80, 5 g / L sucrose, 3 g / L polydextrose, 3 g / L xylan, and 3 g / L pectin. After preparation, the liquid culture medium is fixed to volume with pure water and the pH is adjusted to 6.

8.

5. The bacterial enzyme composite microbial agent product for fruit and vegetable juice fermentation according to claim 2, characterized in that: The bacterial suspensions of Lactobacillus plantarum, Lactobacillus casei, Lactobacillus paracasei and Lactobacillus mucosa fermentation in step (2) are mixed in a ratio of 2:1:1:1 by dry matter weight.

6. The bacterial enzyme composite microbial agent product for fruit and vegetable juice fermentation according to claim 2, characterized in that: The mass ratio of the mixture of pectinase, hemicellulase and cellulase in step (3) is 3:(2-4):(2-4).

7. The bacterial enzyme composite microbial agent product for fruit and vegetable juice fermentation according to claim 2, characterized in that: The mass ratio of the dry matter mass of the bacterial preparation to the enzyme preparation in step (3) is (5-8):1.

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