Method for brewing soy sauce by adopting time-reduced starter propagation

Abstract

The invention discloses a method for brewing soy sauce by adopting time-reduced starter propagation. The method comprises the following steps: (S1) screening bran; (S2) mold starter treatment; (S3) preparing koji; (S4) making koji; and (S5) fermenting. According to the method disclosed by the invention, time-reduced koji making is carried out by adopting a scheme of firstly preparing koji, then formally making koji and the like, so that the levels of the total number of bacterial colonies and the total number of spores of finished koji are greatly reduced, and the enzyme activity of protease is properly controlled by controlling the flour content of fried wheat flour at a relatively low level; the raw material protein decomposition rate of the Cantonese-style high-salt liquid-state fermentation process is improved by matching with a soy sauce fermentation process with mash-making temperature control and no temperature control in the fermentation process, so that the purposes of reducing the consumption of grain raw materials and electric energy in the koji-making process and reducing secondary precipitation of soy sauce are achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of condiment production, and in particular relates to a method for brewing soy sauce by using time-reduced koji making. Background Art

[0002] The high-salt dilute fermentation process has the characteristics of long fermentation time, sufficient post-fermentation, and mellow and fresh flavor of the finished product. It has gradually been adopted by many manufacturers as the brewing process of high-end soy sauce. The high-salt dilute fermentation process can be divided into "Guangzhou-style high-salt dilute fermentation process" and "Japanese-style high-salt dilute fermentation process". In Guangdong, my country, due to the climatic characteristics of abundant heat resources, warm climate and no severe cold in winter, the brewing of soy sauce mainly adopts the Cantonese-style high-salt dilute fermentation process. The Japanese-style high-salt dilute process strictly controls the fermentation temperature and controls the temperature throughout the fermentation process. The raw material protein is decomposed more thoroughly but the energy consumption cost is high; the Cantonese-style high-salt dilute process uses natural temperature sun-dried fermentation, which is greatly affected by the weather, especially when feeding in the high temperature season in summer, the raw material protein is relatively incompletely decomposed. This is mainly because the high temperature in summer promotes microbial metabolism and produces a large amount of rapid acid, which causes the pH of the sauce mash to drop rapidly in the early stage of fermentation, thereby accelerating the inactivation of proteases, and ultimately leading to incomplete decomposition of the raw material protein.

[0003] Koji making is the first important step in soy sauce brewing. There are two ways to make koji: 40 hours and 70 hours. The former is called three-day koji and the latter is called four-day koji. Currently, the three-day koji method is mainly used, and the koji making time generally ranges from 40 to 48 hours. Koji making takes a long time, and the grain loss caused by the growth of microorganisms during the process accounts for 30% of the total. The consumption of grain raw materials and electricity is large, and this link is easily contaminated by various bacteria, causing the finished koji to have problems such as flowery koji and sour koji. Generally, the total number of bacteria in the koji is 10 7 -10 8 Order of magnitude, total number of spores in 10 4 -10 5 At the same time, high protease activity is generally pursued.

[0004] Compared with Japanese and Korean soy sauces, the physical and chemical indicators of domestic soy sauces are basically the same, but the price of domestic soy sauce per unit weight in the domestic market is significantly lower than that of Japanese soy sauce, and the secondary precipitation problem of domestic soy sauce is one of the key reasons for the price difference. The secondary precipitation of soy sauce refers to the khaki to reddish brown precipitation formed at the bottom of the bottle during the storage, transportation and sales of soy sauce after packaging. The secondary precipitation is mainly composed of a large number of bacteria and undecomposed proteins after microscopic examination and component analysis. Therefore, the high level of Daqu bacteria has a greater negative impact on the secondary precipitation of soy sauce. Protease itself is also a protein. The pursuit of high protease activity will increase the consumption of protein in the raw materials and it will dissolve into the crude oil in the form of undecomposed protein, becoming one of the sources of secondary precipitation of soy sauce; the relatively incomplete decomposition of raw material protein in the Cantonese high-salt dilute process is also one of the reasons for the secondary precipitation of soy sauce.

[0005] Therefore, a process method is needed to reduce the level of foreign bacteria in the koji, reduce the consumption of grain raw materials and electricity in the koji-making process, while improving the decomposition rate of protein in the Cantonese high-salt dilute process raw materials and reducing the secondary precipitation of soy sauce, thereby improving the competitiveness of domestic soy sauce. Summary of the invention

[0006] The object of the present invention is to provide a method for brewing soy sauce by reducing the time of koji making.

[0007] The method of the present invention adopts schemes such as pre-making koji first and then formal koji making to reduce the time for koji making, which greatly reduces the levels of the total number of colonies and the total number of spores in the koji, and appropriately controls the protease activity at a relatively low level by controlling the powder content of fried wheat flour, and cooperates with the soy sauce fermentation process in which the temperature of the mash is controlled and the fermentation process is not temperature controlled to improve the raw material protein decomposition rate of the Cantonese high-salt dilute fermentation process, thereby achieving the purpose of reducing the consumption of grain raw materials and electric energy in the koji making process and reducing the secondary precipitation of soy sauce.

[0008] The above-mentioned object of the present invention can be achieved by the following technical scheme: A method for brewing soy sauce by reducing the time of koji making, comprising the following steps:

[0009] (S1) bran screening: screening the bran to obtain flaky bran and powdery bran for later use;

[0010] (S2) treating the seed koji: mixing the soy sauce seed koji with the powdered bran obtained in step (S1) to obtain seed powder;

[0011] (S3) pre-making koji: the sieve-surface bran flakes described in step (S1) are mixed with water, sterilized by steaming, crushed and cooled to 35-38° C., and then mixed with the bacterial seed powder prepared in step (S2), and then placed in a thick-layer mechanical ventilation fermentation device, and cultured at 30-34° C. for 7-9 hours to obtain pre-made koji;

[0012] (S4) koji making: soaking, boiling and cooling the soybeans, mixing them with the roasted wheat flour and the pre-made koji material prepared in step (S3), and culturing them in a thick-layer mechanical ventilation fermentation device or a disc ventilation koji making device for 24 to 28 hours to obtain soy sauce koji;

[0013] (S5) Fermentation: The soy sauce koji prepared in step (S4) is mixed with salt water to make mash and subjected to Cantonese-style high-salt dilute fermentation to obtain soy sauce crude oil.

[0014] In the above method of brewing soy sauce by reducing the time of koji making:

[0015] Preferably, in step (S1), the bran is sieved using a 10-20 mesh sieve, more preferably a 10 mesh sieve.

[0016] Preferably, in step (S2), the mass ratio of the soy sauce koji to the sieve-down powdered bran is 1:0.9-1.1, more preferably 1:1.

[0017] The soy sauce koji can be prepared by conventional technology, or by using commercially available soy sauce koji. It is preferred to prepare the soy sauce koji by the method described in the document "Application of Bean Curd Skin in the Production Technology of Soy Sauce Koji".

[0018] Preferably, in step (S3), the mass ratio of the flaky bran oversize to water is 1:1.1-1.3.

[0019] Preferably, the amount of the bacterial seed powder in step (S3) is 0.4 to 0.6 times the total mass of the flaky bran on the sieve.

[0020] Preferably, in step (S4), the amount of the prefabricated koji material is 3.0 to 3.5‰ of the total mass of the soybeans (unsoaked soybeans), based on the amount of soy sauce koji contained in the prefabricated koji material.

[0021] Preferably, the amount of the fried wheat flour in step (S4) is 0.3 to 0.4 times the total mass of the soybeans (unsoaked soybeans).

[0022] Preferably, the fried wheat flour described in step (S4) is a product obtained by roasting wheat in a boiling roaster at 300-330° C. in an air bath for 30-35 seconds, then air-cooling, and then crushing it in a grinder.

[0023] Preferably, the flour content of the fried wheat flour in step (S4) is controlled at a relatively low level of 19-21%, and the flour content of the fried wheat flour is calculated according to the proportion of the material under the sieve of 30 mesh sieve.

[0024] The powder content of the fried wheat flour of the present invention is 19-21%, which is obviously lower than the powder content of the fried wheat flour of the conventional process (generally above 25%, and the commonly used level is about 30-35%). The high powder content can improve the enzyme activity of soy sauce koji, but at the same time it is easy to be used by microorganisms and is conducive to the large-scale growth and reproduction of microorganisms, which increases the loss of raw materials in the koji making process. The fried wheat flour of the present invention has a low powder content, increases the particle size of the fried wheat flour, and reduces the consumption of raw materials in the koji making process.

[0025] Preferably, the temperature of koji making in step (S4) is 33-38°C when the culture time is 0-7h; 30-34°C when the culture time is 8-15h; and 26-30°C from 16h to the end of the culture.

[0026] Preferably, the koji is turned at least twice during the koji making process in step (S4). When the incubation time reaches 7±1h, the koji material is white and agglomerated, and the koji material temperature rises to above 36°C, the first turning of the koji is carried out; when the incubation time reaches 14-15h, the koji material agglomerates again, and the koji material temperature rises to above 33°C, the second turning of the koji is carried out.

[0027] Preferably, in step (S5), the mass ratio of the soy sauce koji to the brine is 1:1.8-2.1.

[0028] Preferably, in step (S5), the mash temperature is controlled by regulating the temperature of the brine, and then the temperature changes naturally during the entire fermentation process without temperature control, wherein the mash temperature, i.e. the initial temperature of the mash, is 18-20°C, and the fermentation time is 4-5 months.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] (1) The present invention firstly makes Aspergillus oryzae enter the growth and reproduction period by pre-making koji, and then formally makes koji, so that the initial stage of koji making directly enters the large-scale growth and reproduction stage of Aspergillus oryzae, accelerates the koji cultivation process and greatly shortens the koji making time, avoids the large-scale reproduction of miscellaneous bacteria in the koji making process, reduces the loss of raw materials, and obtains the neutral protease of the koji at a moderate level of about 1000U / g, the total number of bacterial colonies decreases by 1 to 3 orders of magnitude, and the total number of spores decreases by 1 to 2 orders of magnitude; at the same time, the koji making time of the present invention is shortened to 24 to 28h, which can save more than 40% of the energy consumption in the koji making process compared with the koji making method of three-day koji;

[0031] (2) The fried wheat flour of the present invention has a low powder content, which increases the particle size of the fried wheat flour and reduces the consumption of raw materials in the koji making process. By controlling the powder content of the fried wheat flour at a low level, the protease activity is properly controlled, the protein consumption in the raw materials is reduced, the decomposition rate of the protein in the Cantonese high-salt dilute process raw materials is improved, and the secondary precipitation of soy sauce is reduced;

[0032] (3) The present invention further cooperates with the soy sauce fermentation process in which the temperature of the mash is controlled but the temperature of the fermentation process is not controlled, thereby ensuring that the quality of the crude soy sauce is not reduced, and improving the raw material protein decomposition rate and quality of the Cantonese high-salt dilute fermentation process, effectively reducing the potential "secondary precipitates" in the soy sauce, thereby effectively reducing the secondary precipitation of the soy sauce during the shelf life. The amount of secondary precipitation formed in the crude soy sauce produced by the method of the present invention is reduced by about 70% compared with the control soy sauce produced by the conventional three-day koji making process and the Cantonese high-salt dilute process, and the effect is significant. DETAILED DESCRIPTION

[0033] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention is further described in detail in conjunction with the embodiments below. It should be understood that the specific embodiments described herein are only used to explain the present invention, belong to the protection scope of the present invention, but are not intended to limit the present invention. For process parameters not specifically noted, reference can be made to the corresponding conventional process technology, and the raw materials used, if not noted, are all commercially available products.

[0034] Example 1

[0035] The method for brewing soy sauce by reducing the time for making koji provided in this embodiment comprises the following steps:

[0036] (S1) bran screening: using a 10-mesh sieve to screen the bran, and obtaining flaky bran on the sieve and powdery bran on the sieve for later use;

[0037] (S2) seed koji processing: placing the soy sauce seed koji and the powdered bran prepared in step (S1) in a blender at a ratio of 1:1 (mass, the same below) and mixing them evenly to obtain seed powder;

[0038] (S3) pre-made koji: the flaky bran prepared in step (S1) is mixed evenly with 1.2 times (by mass, the same below) of water, put into a cooking pot for steaming and sterilization, crushed and cooled to 35-38° C., and then mixed evenly with 0.4 times (by mass, the same below) of the bacterial seed powder prepared in step (S2), placed in a thick-layer mechanical ventilation fermentation tank, and cultured at 30-34° C. for 9 hours to obtain pre-made koji;

[0039] (S4) making koji: after soaking, boiling and cooling the soybeans, the pre-made koji prepared in step (S3) (based on the amount of soy sauce seed koji contained in the pre-made koji) with a powder content of 20% of 0.3 times (unsoaked soybeans) of the roasted wheat flour and 3.2‰ (unsoaked soybeans) of the total mass of the soybean raw materials is evenly mixed, and the mixture is placed in a thick-layer mechanical ventilation fermentation tank or a disc ventilation koji making device, and then the koji is cultured; during this period, the culture temperature is controlled at 33-38° C. for 0-7 hours, and when the culture time reaches 7±1 hours, the koji part is white and agglomerated, and the koji product temperature rises to above 36° C., and the first koji turning is performed; the culture temperature is controlled at 30-34° C. for 8-15 hours, and when the culture time reaches 14-15 hours, the koji agglomerates again, and the koji product temperature rises to above 33° C., and the second koji turning is performed; then the culture temperature is controlled at 26-30° C., and the culture is continued for 24 hours to obtain soy sauce koji;

[0040] The fried wheat flour is a product obtained by roasting wheat in a boiling roaster at 300-330°C in an air bath for 30-35 seconds, air-cooling, and then crushing it in a mill, the same below;

[0041] (S5) Fermentation: The soy sauce koji prepared in step (S4) is mixed with 2.0 times (by mass, the same below) of brine to make mash, and the mash making temperature (i.e., the initial temperature of the mash) is controlled at 18-20° C., and then Cantonese-style high-salt dilute fermentation is performed in a manner that the temperature changes naturally throughout the fermentation process without temperature control, and the soy sauce crude oil is obtained after fermentation for 4 months.

[0042] Example 2

[0043] The method for brewing soy sauce by reducing the time for making koji provided in this embodiment comprises the following steps:

[0044] (S1) bran screening: using a 10-mesh sieve to screen the bran, and obtaining flaky bran on the sieve and powdery bran on the sieve for later use;

[0045] (S2) Seed koji processing: the soy sauce seed koji and the powdered bran prepared in step (S1) are placed in a blender at a ratio of 1:1 and mixed evenly to obtain seed powder.

[0046] (S3) pre-made koji: the flaky bran prepared in step (S1) is mixed evenly with 1.2 times of water, put into a cooking pot for steaming and sterilization, crushed and cooled to 35-38° C., and then mixed evenly with 0.4 times of the bacterial seed powder prepared in step (S2), placed in a thick layer mechanical ventilation fermentation tank, and cultured at 30-34° C. for 7 hours to obtain pre-made koji;

[0047] (S4) making koji: after soaking, boiling and cooling soybeans, the pre-made koji material prepared in step (S3) is mixed evenly with 0.3 times the powder content of 20% of the roasted wheat flour and 3.2‰ of the total mass of the soybean raw materials (based on the amount of soy sauce seed koji contained in the pre-made koji material), and then cultured in a thick-layer mechanical ventilation fermentation tank or a disc ventilation koji making equipment; during this period, the culture temperature is controlled at 33-38° C. for 0-7 hours, and when the culture time reaches 7±1 hours, the koji material part is white and agglomerated, and the koji material temperature rises to above 36° C., and the first koji turning is performed; the culture temperature is controlled at 30-34° C. for 8-15 hours, and when the culture time reaches 14-15 hours, the koji material agglomerates again and the koji material temperature rises to above 33° C., and the second koji turning is performed; then the culture temperature is controlled at 26-30° C., and the culture is cultured for 28 hours to obtain soy sauce koji;

[0048] (S5) Fermentation: The soy sauce koji prepared in step (S4) is mixed with 2.0 times of brine to make mash, and the mash temperature (i.e., the initial temperature of the mash) is controlled at 18-20° C. Thereafter, Cantonese-style high-salt dilute fermentation is performed in a manner that the temperature changes naturally throughout the fermentation process without temperature control, and the soy sauce crude oil is obtained by fermentation for 4 months.

[0049] Example 3

[0050] The method for brewing soy sauce by reducing the time for making koji provided in this embodiment comprises the following steps:

[0051] (S1) bran screening: using a 10-mesh sieve to screen the bran, and obtaining flaky bran on the sieve and powdery bran on the sieve for later use;

[0052] (S2) seed koji processing: placing the soy sauce seed koji and the powdered bran prepared in step (S1) in a blender at a ratio of 1:1 and mixing them evenly to obtain seed powder;

[0053] (S3) pre-made koji: the flaky bran prepared in step (S1) is mixed evenly with 1.2 times of water, put into a cooking pot for steaming and sterilization, crushed and cooled to 35-38° C., and then mixed evenly with 0.6 times of the bacterial seed powder prepared in step (S2), placed in a thick layer mechanical ventilation fermentation tank, and cultured at 30-34° C. for 9 hours to obtain pre-made koji;

[0054] (S4) making koji: after soaking, boiling and cooling soybeans, the pre-made koji material prepared in step (S3) is mixed evenly with 0.3 times the powder content of 20% of the roasted wheat flour and 3.2‰ of the total mass of the soybean raw materials (based on the amount of soy sauce seed koji contained in the pre-made koji material), and then cultured in a thick-layer mechanical ventilation fermentation tank or a disc ventilation koji making equipment; during this period, the culture temperature is controlled at 33-38° C. for 0-7 hours, and when the culture time reaches 7±1 hours, the koji material part is white and agglomerated, and the koji material temperature rises to above 36° C., and the first koji turning is performed; the culture temperature is controlled at 30-34° C. for 8-15 hours, and when the culture time reaches 14-15 hours, the koji material agglomerates again and the koji material temperature rises to above 33° C., and the second koji turning is performed; then the culture temperature is controlled at 26-30° C., and the culture is continued for 24 hours to obtain soy sauce koji;

[0055] (S5) Fermentation: The soy sauce koji prepared in step (S4) is mixed with 2.0 times of brine to make mash, and the mash temperature (i.e., the initial temperature of the mash) is controlled at 18-20° C. Thereafter, Cantonese-style high-salt dilute fermentation is performed in a manner that the temperature changes naturally throughout the fermentation process without temperature control, and the soy sauce crude oil is obtained by fermentation for 4 months.

[0056] Example 4

[0057] The method for brewing soy sauce by reducing the time for making koji provided in this embodiment comprises the following steps:

[0058] (S1) bran screening: using a 10-mesh sieve to screen the bran, and obtaining flaky bran on the sieve and powdery bran on the sieve for later use;

[0059] (S2) seed koji processing: placing the soy sauce seed koji and the powdered bran prepared in step (S1) in a blender at a ratio of 1:1 and mixing them evenly to obtain seed powder;

[0060] (S3) pre-made koji: the flaky bran prepared in step (S1) is mixed evenly with 1.2 times of water, put into a cooking pot for steaming and sterilization, crushed and cooled to 35-38° C., and then mixed evenly with 0.6 times of the bacterial seed powder prepared in step (S2), placed in a thick layer mechanical ventilation fermentation tank, and cultured at 30-34° C. for 7 hours to obtain pre-made koji;

[0061] (S4) making koji: after soaking, boiling and cooling soybeans, the pre-made koji material prepared in step (S3) is mixed evenly with 0.3 times the powder content of 20% of the roasted wheat flour and 3.2‰ of the total mass of the soybean raw materials (based on the amount of soy sauce seed koji contained in the pre-made koji material), and then cultured in a thick-layer mechanical ventilation fermentation tank or a disc ventilation koji making equipment; during this period, the culture temperature is controlled at 33-38° C. for 0-7 hours, and when the culture time reaches 7±1 hours, the koji material part is white and agglomerated, and the koji material temperature rises to above 36° C., and the first koji turning is performed; the culture temperature is controlled at 30-34° C. for 8-15 hours, and when the culture time reaches 14-15 hours, the koji material agglomerates again and the koji material temperature rises to above 33° C., and the second koji turning is performed; then the culture temperature is controlled at 26-30° C., and the culture is cultured for 28 hours to obtain soy sauce koji;

[0062] (S5) Fermentation: The soy sauce koji prepared in step (S4) is mixed with 2.0 times of brine to make mash, and the mash temperature (i.e., the initial temperature of the mash) is controlled at 18-20° C. Thereafter, Cantonese-style high-salt dilute fermentation is performed in a manner that the temperature changes naturally throughout the fermentation process without temperature control, and the soy sauce crude oil is obtained by fermentation for 4 months.

[0063] Comparative Example 1

[0064] In this comparative example, step (S3) of prefabricated koji is not provided, and the prefabricated koji material in step (S4) is replaced with soy sauce seed koji, and the remaining steps are the same as those in Example 1.

[0065] Comparative Example 2

[0066] In step (S4) of this comparative example, the flour content of the roasted wheat flour added during the koji making is 35%, and the remaining steps are the same as those in Example 1.

[0067] Comparative Example 3

[0068] In the fermentation step (S5) of this comparative example, the mash making temperature (i.e., the initial temperature of the mash) is not controlled at 18-20°C. The temperature of the entire fermentation process changes naturally and the Cantonese-style high-salt dilute fermentation is carried out without temperature control. The remaining steps are the same as in Example 1.

[0069] Comparative Example 4

[0070] The method for brewing soy sauce provided in this comparative example comprises the following steps:

[0071] (P1) Koji making: Soak the soybeans, steam and cool them, and then mix them evenly with 0.3 times the powder content of 35% of the roasted wheat flour and 3.2‰ of the total weight of the soybean raw materials to make soy sauce koji, and then culture them in a thick-layer mechanical ventilation fermentation tank or a disc ventilation koji making equipment for 40 hours according to the conventional three-day koji making process to obtain soy sauce koji.

[0072] (P2) Fermentation: The soy sauce koji prepared in step (P1) is mixed with 2.0 times of salt water to make mash, and the mash making temperature is natural temperature. Thereafter, Cantonese-style high-salt dilute fermentation is carried out in a manner that the temperature changes naturally throughout the fermentation process without temperature control, and the soy sauce crude oil is obtained by fermentation for 4 months.

[0073] Comparative Example 5

[0074] (P1) Koji making: Soak the soybeans, steam and cool them, and then mix them evenly with 0.3 times the powder content of 35% of the roasted wheat flour and 3.2‰ of the total weight of the soybean raw materials to make soy sauce koji, and then culture them in a thick-layer mechanical ventilation fermentation tank or a disc ventilation koji making equipment for 44 hours according to the conventional three-day koji making process to obtain soy sauce koji.

[0075] (2) Fermentation: The soy sauce koji prepared in step (P1) is mixed with 2.0 times of brine to prepare mash, and the mash preparation temperature is natural temperature. Thereafter, Cantonese-style high-salt dilute fermentation is performed in a manner that the temperature changes naturally throughout the fermentation process without temperature control, and the soy sauce crude oil is obtained by fermentation for 4 months.

[0076] Implementation effect comparison

[0077] The neutral protease activity, micro-inspection indexes and physicochemical indexes of the corresponding crude soy sauce oil of the soy sauce koji obtained by culturing in Examples 1 to 4 and Comparative Examples 1 to 5 were detected. At the same time, the soy sauce secondary precipitation amount was detected for the crude soy sauce oil of Examples 1 to 4 and Comparative Examples 1 to 5 using the same measurement method. The indexes of the soy sauce koji, the physicochemical indexes of the crude soy sauce oil and the secondary precipitation amount of the soy sauce are shown in Table 1.

[0078] Measuring method for secondary precipitation of soy sauce: the finished soy sauce is obtained after blending the crude soy sauce, diatomaceous earth filtration, sterilization and packaging, and then placed at a constant temperature of 30°C for 60 days, centrifuged at 0°C and 10,000 r / min for 20 minutes, the supernatant is removed, the precipitate is collected, and dried at 105°C to constant weight, and the production of secondary precipitation of soy sauce is calculated.

[0079] Table 1 Summary of results of the cultivation of soy sauce koji obtained in Examples 1 to 4 and Comparative Examples 1 to 5, the indicators of the soy sauce crude oil obtained by fermentation, and the amount of soy sauce secondary precipitation

[0080]

[0081]

[0082] As can be seen from Table 1, Example 1 adopts the three technical means of pre-making koji first and then formal koji making, reducing the powder content of fried wheat flour and controlling the temperature of mash making, and not controlling the temperature during the fermentation process, while Comparative Example 1 does not adopt the technical means of pre-making koji first and then formal koji making, and only adopts the two technical means of reducing the powder content of fried wheat flour and controlling the temperature of mash making, and not controlling the temperature during the fermentation process (the others are consistent with Implementation 1). Under this condition, the micro-inspection level of the soy sauce koji obtained in Comparative Example 1 is basically equivalent to the micro-inspection level of the soy sauce koji obtained in Example 1, but the neutral protease activity is only 492U / g, which is significantly lower than that in Example 1. 1; at the same time, the physicochemical indicators of the crude soy sauce obtained by fermentation in Comparative Example 1 are significantly lower than those of the crude soy sauce obtained by fermentation in Example 1, and the amount of soy sauce secondary precipitation of the crude soy sauce obtained by fermentation in Comparative Example 1 is significantly higher than that of the crude soy sauce obtained by fermentation in Example 1, and is only slightly lower than that of the crude soy sauce obtained by fermentation in the old process (Comparative Examples 4-5), with no obvious improvement effect, indicating that the technical means of pre-making koji first and then formally making koji in the present invention is not adopted, and only the latter two technical means are adopted, which cannot effectively reduce the amount of soy sauce secondary precipitation.

[0083] The powder content of the fried wheat flour used in the koji making according to Example 1 is 15% lower than that of the comparative example 2. The amino acid nitrogen, reducing sugar and total nitrogen of the crude soy sauce obtained by fermentation in Example 1 are higher than those of the crude soy sauce obtained by fermentation in Comparative Example 2, indicating that the technical means of reducing the powder content of the fried wheat flour adopted in the present invention can reduce the consumption of raw materials and improve the physical and chemical indicators of the crude soy sauce; the amino acid nitrogen and amino acid generation rate of the crude soy sauce obtained by fermentation in Example 1 are 0.07 g / 100 mL and 4% higher than those of the crude soy sauce obtained by fermentation in Comparative Example 3, respectively, indicating that the technical means of controlling the temperature during mash making and not controlling the temperature during fermentation in the present invention can improve the decomposition rate of raw material protein; at the same time, the soy sauce secondary precipitation amount of the crude soy sauce obtained by fermentation in Example 1 is lower than the soy sauce secondary precipitation amount of the crude soy sauce obtained by fermentation in Comparative Examples 2 and 3, indicating that the simultaneous use of the three technical means of the present invention has the best effect on reducing the secondary precipitation amount of soy sauce.

[0084] In addition, according to the new soy sauce Daqu cultivation process of the present invention of pre-making koji first and then formally making koji, the average activity of neutral protease in the soy sauce Daqu was 1015U / g, which was at a moderate level, 1140U / g lower than that in the comparative example 4-5, which was reduced by about 50%; the total number of colonies in the soy sauce Daqu obtained in the examples 1-4 was 10 5 ~10 6 The level is 10 higher than that of the total number of soy sauce Daqu colonies in the comparative example 4-5. 7 ~10 8 The total number of spores in soy sauce obtained in Example 1-4 was 10 3 ~10 4The level is 10 higher than that of the total number of spores in soy sauce 4-5 in comparative example 5 It dropped by 1 to 2 orders of magnitude, indicating that the new process for cultivating soy sauce koji of the present invention can greatly reduce the amount of foreign bacteria in the koji.

[0085] The average total acid value of the crude soy sauce obtained by fermentation in Example 1-4 is 1.94 g / 100 mL, which is basically the same as the average total acid value of the crude soy sauce obtained by fermentation in Comparative Example 4-5, which is 1.93 g / 100 mL; the average amino acid nitrogen value is 1.04 g / 100 mL, which is 0.11 g / 100 mL higher than the average amino acid nitrogen value of the crude soy sauce obtained by fermentation in Comparative Example 4-5, which is 0.93 g / 100 mL; the average reducing sugar value is 4.90 g / 100 mL, which is 1.08 g / 100 mL higher than the average reducing sugar value of the crude soy sauce obtained by fermentation in Comparative Example 4-5, which is 3.82 g / 100 mL. The average total nitrogen value is 1.53 g / 100 mL, which is 0.08 g / 100 mL higher than the average total nitrogen value of 1.45 g / 100 mL of the crude soy sauce obtained by fermentation in Comparative Examples 4-5; the average amino acid generation rate is 68.2%, which is 4.2% higher than the average amino acid generation rate of 64.0% of the crude soy sauce obtained by fermentation in Comparative Examples 4-5. The physicochemical indices of the crude soy sauce obtained by fermentation using the new process of the present invention are better than those of the crude soy sauce obtained by fermentation using the old process (Comparative Examples 4-5), and the amino acid generation rate is high, indicating that the raw material protein decomposition of the new process of the present invention is more thorough.

[0086] The amount of soy sauce secondary precipitation generated by fermenting the soy sauce crude oil using the process technology of the present invention according to Examples 1-4 is much less than that of Comparative Examples 4-5. After the overall application of the new process technology of the present invention, the amount of soy sauce secondary precipitation is reduced by 71.3% compared with the old process.

[0087] In summary, the soy sauce Daqu miscellaneous bacteria obtained by cultivating the process technology provided by the present invention are reduced by an average of 2 orders of magnitude compared with the old process, and the core indicator neutral protease enzyme activity is reduced by about 50% compared with the old process, but the corresponding fermentation obtained soy sauce crude amino acid nitrogen, reducing sugar, total nitrogen, and amino acid production rate are higher than the old process and the secondary precipitation amount of soy sauce is greatly reduced compared with the old process, that is to say, the process technology of the present invention can reduce the loss of raw materials in the koji process and improve the amino acid nitrogen, reducing sugar, etc. of its soy sauce crude oil, and improve the decomposition rate of raw material protein in the Cantonese high-salt dilute fermentation process, and effectively reduce the secondary precipitation amount of soy sauce shelf life. At the same time, the koji making time can be shortened to 24-28h, and the conventional three-day koji making process can save more than 40% of the energy consumption in the koji making process, greatly reducing the energy consumption cost and improving the product competitiveness. The process technology provided by the present invention has a larger innate advantage than the conventional process technology.

[0088] The above are preferred embodiments of the present invention, but are not limitations of the present invention. The present invention may also be summarized in other specific forms that do not violate the spirit or main features of the present invention. Without departing from the above basic technical ideas of the present invention, the present invention may also make other various forms of equivalent modifications, replacements or changes, all of which fall within the protection scope of the present invention.

Claims

1. A method for brewing soy sauce by reducing the time of koji making, characterized in that: The following steps are involved: (S1) bran screening: screening the bran to obtain flaky bran and powdery bran for later use; (S2) treating the seed koji: mixing the soy sauce seed koji with the powdered bran obtained in step (S1) to obtain seed powder; (S3) pre-making koji: the sieve-surface bran flakes described in step (S1) are mixed with water, sterilized by steaming, crushed and cooled to 35-38° C., and then mixed with the bacterial seed powder prepared in step (S2), and then placed in a thick-layer mechanical ventilation fermentation device, and cultured at 30-34° C. for 7-9 hours to obtain pre-made koji; (S4) koji making: soaking, boiling and cooling the soybeans, mixing them with the roasted wheat flour and the pre-made koji material prepared in step (S3), and culturing them in a thick-layer mechanical ventilation fermentation device or a disc ventilation koji making device for 24 to 28 hours to obtain soy sauce koji; (S5) Fermentation: The soy sauce koji prepared in step (S4) is mixed with salt water to make mash and subjected to Cantonese-style high-salt dilute fermentation to obtain soy sauce crude oil.

2. The method for brewing soy sauce by reducing the time for making koji according to claim 1, characterized in that: In step (S1), the bran is sieved with a 10-20 mesh sieve; in step (S2), the mass ratio of the soy sauce koji to the powdered bran under the sieve is 1:0.9-1.

1.

3. The method for brewing soy sauce by reducing the time for making koji according to claim 1, characterized in that: The mass ratio of the flaky bran on the sieve to water in step (S3) is 1:1.1-1.3; the amount of the bacterial seed powder in step (S3) is 0.4-0.6 times the total mass of the flaky bran on the sieve.

4. The method for brewing soy sauce by reducing the time for making koji according to claim 1, characterized in that: In step (S4), the amount of the prefabricated koji material is 3.0 to 3.5‰ of the total mass of the soybeans, based on the amount of soy sauce koji contained in the prefabricated koji material; the amount of the fried wheat flour in step (S4) is 0.3 to 0.4 times the total mass of the soybeans.

5. The method for brewing soy sauce by reducing the time for making koji according to claim 1, characterized in that: The fried wheat flour described in step (S4) is a product obtained by roasting wheat in a boiling roaster at 300-330° C. in an air bath for 30-35 seconds, then air-cooling, and then crushing with a grinder.

6. The method for brewing soy sauce by reducing the time for making koji according to claim 1, characterized in that: The powder content of the fried wheat flour in step (S4) is controlled at 19-21%, and the powder content of the fried wheat flour is calculated according to the proportion of the material under the 30-mesh sieve.

7. The method for brewing soy sauce by reducing the time for making koji according to claim 1, characterized in that: The temperature of koji making in step (S4) is 33-38°C when the culture time is 0-7h; 30-34°C when the culture time is 8-15h; and 26-30°C from 16h to the end of the culture.

8. The method for brewing soy sauce by reducing the time for making koji according to claim 1, characterized in that: In step (S4), the koji is turned at least twice during the koji making process. When the incubation time reaches 7±1h, the koji material is white and agglomerated, and the koji material temperature rises to above 36°C, the koji is turned for the first time. When the incubation time reaches 14-15h, the koji material agglomerates again, and the koji material temperature rises to above 33°C, the koji is turned for the second time.

9. The method for brewing soy sauce by reducing the time for making koji according to claim 1, characterized in that: In step (S5), the mass ratio of the soy sauce koji to the brine is 1:1.8-2.

1.

10. The method for brewing soy sauce by reducing the time for making koji according to claim 1, characterized in that: In step (S5), the temperature of the mash is controlled by regulating the temperature of the brine, and then the temperature changes naturally during the entire fermentation process without temperature control. The mash temperature, i.e., the initial temperature of the mash, is 18-20°C, and the fermentation time is 4-5 months.

Images