Study on the fermentation process of soy sauce of microbial fermentation

soy sauce commonly known as tantacourse oil, mainly made from soybeans, wheat, salt through the process of making oil, fermentation, etc., is very common microbial fermentation food, the following small editor will simply introduce you to the fermentation process of soy sauce:p style""text-center: "img src" "alt" "microbial fermentation soy sauce fermentation process research" Microbial fermentation soy sauce fermentation process research",, process classificationthe actual situation of China's soy sauce fermentation process, can be roughly divided into the following four categories:1, high-salt diluted fermentationstrictly in the sense of high-salt sparse fermentation should refer to the introduction of the brewing process from Japan, such as Beijing and Tianguang, Shijiazhuang Jane, Shaoxing, Kunshan turtle, etc2, goofing fermentationoriginally widely used in the southern part of the large can watering process, was later used by a brewing in Shanghai to improve the low-salt solid fermentation process, in the late fermentation of the watering, trying to improve the flavor, and gradually spread throughout the country3, low-salt solid fermentationwhich is a process generally implemented in the 1970s, usually with skimmed soybeans and bran as raw materials, after cooking, after the crank and concentration of less than 15The salt water is mixed into a solid sauce for thermal fermentation80% of China's soy sauce brewing enterprises use this process4, the traditional sauce tank fermentationthe traditional process retained in China's sauce garden, that is, with large cylinder fermentation, sun exposure, summer sauce, autumn and winter oilAt present, some of the smaller enterprises are still insisting, such as: Zhejiang Shendang Sauce Garden, Huai'an PuLou Sauce Garden, Cebu Sanyuan Sauce Garden, Jiangyin Huaxi Food Brewing CompanyII, various process instructions 1, high-salt thin fermentation processthe key point of the high-salt thin fermentation process is that the fermentation stage is in the state of high salinity, salt water 19 to 20 wave of beauty, the volume of salt water added is 1.1 to 1.2 times the volume of raw materials (used to call 11-12 water), the salt salt is 17% 118% Because of the large salt content, it can make the fermentation temperature lower, is conducive to a variety of salt-resistant microbial effects, fermentation cycle is long, usually around 180 d, is conducive to more thorough fermentation, while adding lactic acid bacteria, yeast, produce organic acids, alcohols, esters and other substances, in order to show aroma, improve flavor prepared conditions Its biggest feature is that there are more aromas, up to more than 300 kinds, other processes can not be replaced how to define the high-salt dilute fermentation process? There are three points: First, the ratio of raw materials The raw material is skimmed soybean and wheat, and the wheat content in the ratio can not be too much less than the skimmed soybean Second, the fermentation temperature is controlled below 35 degrees C, which is conducive to yeast growth Third, salt-resistant yeast should be involved in fermentation, can measure the ethanol content In line with the above conditions of production of products can be light color, pure fragrance attack people, in cold mixing, eating can highlight the original taste of food, in order to be named after the high-salt thin fermentation process The food industry processes baked eel, roasted purple vegetables, baking snowcakes and other alcoholic food, must also use such soy sauce based on the characteristics and requirements of this process, there must be a certain number of temperature control fermentation containers, yeast seed tanks, refrigeration equipment, oil extraction equipment, etc , large investment, capital occupation, so the current domestic enterprises to adopt the process is not much The intherioning process in the south and some solid fermentation processes, and even the process of watering in low-salt solid fermentation, can be included in the category of high-salt thinning fermentation 2, the watering process ancient brewing soy sauce with a large cylinder fermentation, inserted in the middle of the bamboo, every day from the bamboo pickaxe out of the juice water poured on the surface of the sauce, so that it is evenly up and down, can regulate the temperature, but also let the microbes get oxygen When oiling, the soy sauce is drawn directly from the bamboo cocoon, eliminating the pressing equipment High-salt fermentation in the south follows this process, but switching to large cans or large pools, often worried about poor oil, reduces starchy ingredients and even adds gluten to the ingredient symbiotic formula in the 1980s, some enterprises producing low-salt solid soy sauce pulled out the bottom of the sauce of the fermentation pool and poured it onto the surface of the sauce, and did better to lower the temperature in the late stage of low-salt fermentation, add sugar, salt, etc to be watered, and even add yeast, the ultimate goal is to improve the flavor of soy sauce That is, if you need to improve flavor, you need to increase the metabolism of sugar, so you need yeast microorganisms to participate in the reaction, and yeast reproduction temperature can not be too high, so it is necessary to reduce the temperature, and reduce the temperature to increase salinity and moisture, which is a low-salt solid fermentation process to improve one way at present, many production of low-salt solid soy sauce in the early stage of the fermentation began to water, even if not to reduce the temperature, do not increase salinity, do not increase the sugar, the composition of the sauce, temperature uniformity are good, after the oil will be smooth, and the soy sauce poured out of the bright color, no scorching taste 3, low-salt solid fermentation process the process is based on salt-free fermentation The concentration of salt water controlled is about 12 wave of methane, the ratio of water to raw material is 1:1, and the fermentation temperature is above 42 degrees C Because of the low salt content, less water, the concentration of the reactants becomes larger, the product temperature is easily raised, so the maturation period is shortened Coupled with simple technology, less investment, so after the 1970s in the country quickly spread But such a process also has a single taste of the product, dim color, focus and heavy taste and other defects At present, by reducing fermentation temperature, prolonging fermentation cycle and other methods to improve the process, the most common is to use the way toimprove the flavor low-salt solid fermentation process solves the problem of soy sauce production in China, the production cost is also low, the product is suitable for red cooking Therefore, the large-scale production of cooking soy sauce enterprises can use low-salt solid-state fermentation process to solve the problemof large yield, low cost, there is no need to rigidly into the category of high-salt thin fermentation 4, the traditional sauce cylinder fermentation habits are also known as pure natural fermentation, many old sauce garden using this process to produce regional products The main raw materials can be used as soybeans, skimmed soybeans or wheat, retain the traditional process, but also all flour as raw materials, such as the sweet oil in the northern part of the region fermentation methods are divided into solid and liquid The former is in the mixing time to add more than twice the salt water for fermentation, semi-solid, fermentation mature with two oil water diluted oil, the latter is in the mixing time more than twice the salt water fermentation, is thin Solid fermentation when solid phase and gas contact more, high temperature bacteria metabolism is better, so the aroma is heavier, but also save large cylinder; The common feature of the two is the open fermentation of large cylinders, open the lid of the cylinder on a sunny day sun exposure, fermentation throughout the summer, to the autumn oil, with wood or inserted bamboo, oil extraction the traditional sauce tank fermentation when the temperature is high, so yeast growth is more difficult, but pure natural conditions, high salinity, solid liquid surface and air full contact for other beneficial bacteria growth and reproduction opportunities, especially high-temperature bacteria to grow, its metabolic scent of the proportion of materials, such as tetraethyl-based wood phenol, which is the main ingredient of the sauce Because is a natural fermentation, so many species of bacteria, enzyme system, product sauce fragrance rich, bright color, concentration, heavy after taste, is the older generation of tongue on the indelible memory, welcomed by the local people the process due to poor equipment, labor intensity, low output, poor labor efficiency, large area, can not compete with large-scale production, products can only face the local market, development is more difficult Now there are many such old sauce garden and local tourism combined, as an intangible cultural heritage to retain, on the one hand to meet the needs of some local people, on the other hand, but also to be able to carry on the traditional process of our country three, process quality control point at present, China's most common use of low-salt solid fermentation process, should be controlled is the sauce moisture, sauce salinity, fermentation temperature and fermentation time, usually the salt content of the sauce in 7% to 9%, moisture in 50% of a 55%, fermentation temperature at about 45 degrees C, fermentation time can not be less than 15 d Sometimes factories can not keep up with the production of arbitrary increases in fermentation temperature, or unlimited reduction of fermentation cycle, will destroy the stability of product quality Low-salt solid fermentation must be mixed with salt water and cranks, clumps will make the sauce smell, affect the quality If the introduction of watering method, it does have a great effect on improving flavor 1, the focus of the watering process the formula of starch raw materials can not be less, especially can not be all with bran instead of wheat Can be in the early stage to skimmed soy, bran-based, later in the watering when the choice of sugar, wine and other sugar substances Control the salinity and temperature when poured Ensure that the sauce has a salinity of 18 g/100 mL and a temperature below 35 degrees C maintain good fermentation sanitation conditions When watered and fermented, the sauce is in full contact with the air, and this temperature and sugar are suitable for yeast growth There is such a change in yeast in the sauce: hetero-yeast one main yeast, one mature yeast, one membrane yeast Especially in the southern region will be prone to mold, so it is necessary to cover the cover salt in time to avoid the production of membrane yeast over-reproduction 2, the main point of the traditional sauce cylinder fermentation process raw material ratio does not use bran, can not use rice shell, but with flour or wheat to maintain starch content production sites to form a good microbiome, not affected by the surrounding environment, do not move easily If you move, you will also need to move the fermented sauce to a new site in advance to create a good microbial environment to turn the cylinder or stir in time Open the cylinder head on a sunny day and let it shine at night If it is a solid sauce fermentation, should often turn the sauce, the surface of the sund sauce pressure to the bottom, the sauce under the sauce tank turned up, a week of domestic demand for turning the cylinder; All of this should be done in the morning 3, high-salt diluted fermentation process in the implementation of the easily aproblem 1) pre-fermentation stage dyeing bacteria, enzyme system incomplete Japanese music time guaranteed at 72 h The control temperature in the first 12 hours was 27 to 28 degrees C, 16 hours to 30 degrees C, maintained 28 h, and then gradually dropped to 25 degrees C until the music Domestic high-salt thin fermentation process usually needs 48 h, the main reason is open-type music, air pollution, dare not cryogenic, the temperature is not less than 30 degrees C, fear of mold pollution, so in two days the music has matured The timing of 48 h does not guarantee the production of glutamine enzymes, so the amount of glutamate produced by many high-salt diluted fermentation processes is not high The improvement is to control the sanitation of the production area and the curveroom, while installing air purification facilities at the air inlet of the music 2) fermentation temperature control is not strict under normal conditions into fermentation when the temperature of the sauce is at 15 degrees C, to control the proliferation of hybrids At this time pH value of 5.8 or more, lactic acid bacteria is not easy to grow, non-salt-resistant lactic acid bacteria died The most suitable temperature of salt-resistant soy sauce lactic acid bacteria is 25 to 30 degrees C, when the temperature gradually rises to 25 degrees C, salt-resistant lactic acid bacteria growth, so that the content of lactic acid in the sauce up to 1.0%, and stable at this level When the pH value reaches 5 or less, the acid-resistant lactic acid bacteria do not adapt, yeast began to multiply, 100 days when the alcohol content reached 2% to 3%, after a gradual decline, maintained at more than 2% Domestic enterprises difficult to do is the temperature to maintain, it is possible that the pH rate fell quickly, lactic acid content rose, resulting in the total acid exceeding the standard Fermentation equipment should be equipped with refrigeration equipment, the key is to do a good job of temperature management 3) into the fermentation stage stirring is not scientific now stirring more air compressor, should be equipped with air purification settings Pre-fermentation, to avoid the clumps to absorb salt water too slowly, to grow anaerobic bacteria reproduction, should be stirred every day Yeast growth stage, can be stirred every 5 to 6 d, conducive to the production of alcohol Stir every 10 to 15 d later Many enterprises in practice are stirred once a day, although easy to work, but the product quality has a great impact the above," the purpose of the soy sauce production process classification is to arouse the industry's attention to the traditional process, so that enterprises form a set of scientific, complete and stable process procedures, so that operators know how to do, so as to stabilize product quality We can't say which process is the best, it is based on the actual situation of the enterprise and their own sales ability to decide However, it is emphasized that once the process is determined, it is necessary to strictly control the basic requirements of this process to operate If the use of high-salt diluted fermentation process, the production of product alcohol flavor is very good, alcohol content of more than 1%, if the use of low-salt solid fermentation process, then the product color, taste, concentration stability, low cost, for red cooking is very practical;