Pickled marinated meat product and preparation method thereof

Abstract

The invention belongs to the technical field of food processing, and discloses a preparation method of a stewed meat product, which comprises the following steps: stewing marinating soup, cooling, adding lactobacillus curvatus, and uniformly mixing to obtain a fermentation soak solution; boiling and cooling the raw material meat, adding the raw material meat into the fermentation soak solution, soaking, packaging and storing. Wherein the inoculation amount of the lactobacillus curvatus is 0.01-0.04% of the mass of the marinating soup. On the basis of a traditional soak solution preparation formula, a probiotic fermentation process is adopted, and through first-stage pre-fermentation and second-stage soak fermentation, the soak solution rapidly grows to form dominant bacteria, so that growth of other harmful bacteria is inhibited, and harmful microorganisms of the product in the soaking stage and the later storage stage are effectively controlled.

Description

Technical Field

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

[0002] Pickled meat products are made by pre-cooking and cooling the raw meat, and then soaking it in seasoning soup at a lower temperature or refrigerated conditions to obtain a crisp and firm taste, and a fresh and spicy flavor. However, since the soaking time of this type of product is long, generally more than 20 hours, it is easy to cause the growth of harmful microorganisms, and since there is no subsequent heat processing, and the product has a lot of marinade after soaking, it is not easy to package and preserve, making the control of microorganisms particularly difficult. The processing of pickled products mainly depends on the "cold soaking" process. Its process characteristics determine that the process of soaking and flavoring is inevitably accompanied by "spontaneous" fermentation, mainly the proliferation of lactic acid bacteria. As the soaking time increases, the pH value decreases, and the lactic acid bacteria ferment to produce a unique flavor. However, there are various types of lactic acid bacteria formed by spontaneous growth, and many of them produce gas. If the subsequent sterilization is not in place, it will seriously affect the product quality.

[0003] For products sold at room temperature, heat sterilization, irradiation sterilization, and the addition of preservatives are commonly used for sterilization and preservation. Heat sterilization seriously damages the raw materials and destroys the sensory and nutritional properties of the products. Although irradiation can achieve a good sterilization effect, the adverse effects on the sensory, texture, and flavor of the products cannot be completely eliminated. High-dose irradiation treatment will also generate irradiation odor and cause the product to change color. At the same time, no matter what sterilization method is used, the effectiveness of the sterilization depends not only on the sterilization conditions, but also on the state of the initial bacteria in the product. If the initial bacteria in the product are complex and numerous, especially some microorganisms with spores, it is difficult to completely kill them through subsequent sterilization. For low-temperature refrigerated short-shelf products, although there is no need to completely kill the microorganisms, the shelf life of the product will be greatly shortened.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] To solve the above problems, the present invention provides a pickled meat product and a preparation method thereof, a two-stage immersion and braising process, which achieves the purpose of inhibiting the growth of harmful microorganisms without adding preservatives, increasing product flavor and improving product functionality through the microbial regulation during the preparation of braising soup, immersion and braising, and low-temperature refrigeration.

[0006] To achieve the above purpose, the technical solution provided by the present invention is: The method for preparing a marinated meat product comprises: boiling and cooling the brine, adding Lactobacillus curvatum and mixing evenly into a fermentation soaking liquid; The raw meat is boiled and cooled, and then added into the fermentation soaking liquid for soaking, packaging and storage; Among them, the inoculation amount of Lactobacillus curvatus is 0.01~0.04% of the mass of the braising soup.

[0007] Preferably, the raw materials of the braising soup include, by weight, 100 parts of water, 10-15 parts of wild pepper, 1.5-2.5 parts of ginger, 0.2-0.5 parts of star anise, 0.2-0.5 parts of cinnamon, 2.5-3.5 parts of salt, 0.4-0.8 parts of chicken essence, and 1.0-2.0 parts of white vinegar.

[0008] Preferably, the brewing is performed by soaking at 8-15° C. for 20-24 hours.

[0009] Preferably, the mass ratio of raw meat to fermentation soaking liquid is 1:1~1.5.

[0010] Preferably, the raw meat is divided before soaking.

[0011] Preferably, if the packaged product has not been sterilized, it is stored in a refrigerated state at 4-6°C; if the packaged product has been sterilized, it is stored at room temperature.

[0012] Preferably, the composite bacteria is added and pre-fermented at 22° C. for 24 hours to obtain the fermentation soaking liquid.

[0013] The invention also discloses a marinated meat product obtained by any of the above preparation methods.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention adopts a probiotic fermentation process based on the traditional soaking liquid preparation formula. Through the first stage pre-fermentation and the second stage soaking fermentation, the probiotics can grow rapidly to form dominant bacteria, thereby inhibiting the growth of other harmful bacteria, so that the harmful microorganisms of the product in the soaking stage and the later storage stage can be effectively controlled.

[0015] 2. The present invention selects Lactobacillus curvatus, which is non-spore-free, non-gas-producing, and has the characteristics of acid resistance and low-temperature resistance. Its growth temperature range is from 5°C to 53°C, and it can normally exert its antibacterial effect under the temperature condition of 8~15°C in the product soaking process.

[0016] 3. The probiotics used in the present invention act on the raw meat, and increase the flavor of the product by moderately decomposing protein, fat and carbohydrates. At the same time, lactic acid bacteria have beneficial effects on the human body, and the product has the functionality of regulating intestinal health.

[0017] 4. The present invention adopts a two-stage fermentation process. In the first stage of fermentation, a medium-high temperature rapid fermentation process is adopted to promote the activation of bacteria and enhance the pickling and fermentation capacity of the soaking liquid; in the second stage, a low-temperature soaking fermentation is adopted to effectively maintain the flavor and mouthfeel of the meat. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments.It should be understood that these descriptions are exemplary only, and are not intended to limit the scope of the present invention.In addition, in the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.Unspecified conditions in the embodiments are carried out according to the conditions of normal conditions or manufacturer recommendations.Reagents used or instruments that do not specify manufacturers are conventional products that can be purchased and obtained commercially.

[0019] In the following examples, "parts" refer to "parts by weight".

[0020] Example 1 Preparation method of marinated meat products (this example is used to illustrate the screening of lactic acid bacteria): The braising soup is prepared according to the proportion of 100 parts of water, 12 parts of wild pepper, 2.0 parts of ginger, 0.3 parts of star anise, 0.3 parts of cinnamon, 2.5 parts of salt, 0.5 parts of chicken essence and 1.5 parts of white vinegar. After the water boils, keep it at a slight boil and simmer for 30 minutes. Remove the residue and let it cool for later use.

[0021] Add lactic acid bacteria to the cooled brine and mix evenly to obtain a fermented soaking liquid; The raw rabbit meat is boiled and cooled, then added to the fermentation soaking liquid and soaked at 15°C for 24 hours, and then packaged and stored; the mass ratio of rabbit meat to fermentation soaking liquid is 1:1.2, wherein the lactic acid bacteria inoculation amount is 0.02% of the mass of the brine. The lactic acid bacteria are set into the following groups: Blank control group (CK): no probiotics were added.

[0022] Pediococcus acidilactici (PA): Add 0.02% of Pediococcus acidilactici to the soaking solution Lactobacillus curvature group (LC): 0.02% Lactobacillus curvature was added to the soaking liquid Sake Lactobacillus group (LS): 0.02% Sake Lactobacillus was added to the soaking liquid The physical, chemical and microbiological indices of the soaked rabbit meat were measured. The results are shown in Table 1.

[0023] Table 1 Effects of three bacteria on the physicochemical and microbiological properties of pickled rabbit meat .

[0024] After adding lactic acid bacteria, the pH of rabbit meat products was lower than that of the blank group. The lower pH is conducive to inhibiting the growth of acid-intolerant spoilage bacteria, but in practice, when the pH is less than 5.3, the product will produce a noticeable sour taste and affect its sensory perception. As shown in Table 1, the pH of the lactic acid Pediococcus and sake Lactobacillus groups are both lower than 5.3, and the sake Lactobacillus group has the lowest pH value, mainly because sake Lactobacillus has a strong acid-producing ability. Lactobacillus curvatum can moderately reduce the pH without making it too low; The content of volatile basic nitrogen (TVB-N) is an important indicator for judging the freshness of meat. The TVB-N of the bacteria-added group was lower than that of the control group, while Lactobacillus sakei and Lactobacillus curvatus had better effects. Malondialdehyde (TBA) is the final product of animal lipid oxidation and decomposition. The larger the value, the deeper the degree of lipid oxidation in meat products. Lactobacillus curvatus can significantly reduce lipid oxidation in rabbit meat. According to the results of microbial testing, due to the addition of probiotics, the total colony count and the number of lactic acid bacteria in the bacteria-added group were higher than those in the control group, but the proliferation of lactic acid bacteria in the PA group was not as good as the other two bacteria. This was because the temperature of the soaking fermentation was 15°C, and the reproduction ability of lactic acid bacteria decreased at low temperatures, so the effect was limited.

[0025] Microbial diversity (Shannon index) reflects the number and distribution of microbial species in the product. The higher the value, the more types and numbers of microorganisms there are, and the higher the degree of product contamination or bacterial reproduction. The test results show that the Shannon index of the bacteria-added group is much lower than that of the control group, indicating that the lactic acid bacteria in the bacteria-added group have become the dominant bacteria in the system and inhibited the growth of other microorganisms. However, in comparison, the PA group has the worst effect, and the role of lactic acid bacteria in inhibiting the growth of bacteria is not as good as the other two bacteria.

[0026] Comparing the three bacteria, without affecting the taste of the product, Lactobacillus curvatum has a significant better effect in the LS and LC groups, and the inhibitory oxidation effect of Lactobacillus curvatum is significantly better than the other two bacteria, and the degree of product oxidation is greatly reduced compared with the control group.

[0027] Example 2 This example is used to illustrate the determination of pre-fermentation conditions.

[0028] Pickled brine products are very susceptible to bacterial contamination or deterioration due to the growth of corrupt microorganisms during the long soaking time. On the other hand, the soaking temperature used in the processing process is generally around 10°C, and probiotics may grow slowly due to the lower soaking temperature. Therefore, the soaking liquid needs to proliferate rapidly after inoculation of probiotics. To this end, the soaking liquid is pre-fermented under certain temperature conditions for a period of time, and then used to soak meat materials to improve the fermentation capacity of the strains. After pre-fermentation, the microbial characteristics and sensory quality of the soaking liquid are measured.

[0029] The preparation of the brine is as in Example 1.

[0030] 0.02% of the mass of the brine was added to the cooled brine, and the mixture was evenly mixed. The brine was pre-fermented at the pre-fermentation temperature and time in Table 3 to obtain a fermented soaking liquid.

[0031] The total colony count and lactic acid bacteria count were determined according to GB 4789.2-2016 “National Food Safety Standard for Microbiological Examination of Foods - Determination of Total Colony Count” and GB4789.35-2016 “National Food Safety Standard for Microbiological Examination of Foods - Detection of Lactic Acid Bacteria” respectively. The Biolog-ECO microbial identification system was used to determine microbial diversity. The sensory evaluation was conducted by a 10-member evaluation team and the scores were given according to the items in Table 2.

[0032] Table 2 Sensory evaluation standards .

[0033] The test groups and test results are shown in Table 3.

[0034] Table 3 Effects of pre-fermentation process on microbial and sensory quality of soaking liquid .

[0035] The results showed that the number of lactic acid bacteria in the pre-fermentation group was higher than that in the CK group, and because the suitable growth temperature of lactic acid bacteria is 30℃, the proliferation effect of lactic acid bacteria in the pre-fermentation group at 30℃ was more obvious. However, from the results of the total colony count and the Shannon index of microbial diversity, the total colony count also showed an increasing trend with the increase of fermentation temperature. Although the total colony count of the control group was the lowest, the Shannon index was the highest, indicating that in addition to lactic acid bacteria, there were a large number of other microorganisms in the system under the traditional process. At the same time, the Shannon index of the 15℃ and 30℃ pre-fermentation groups was also significantly higher than that of the 22℃ pre-fermentation group. This is because lactic acid bacteria grow slowly at 15℃. During this process, some other low-temperature-resistant microorganisms multiply in large numbers, which increases the content of miscellaneous bacteria in the system; although 30℃ is suitable for the reproduction of lactic acid bacteria, it is also suitable for the growth and reproduction of most microorganisms, so the microbial diversity in the system is also high. From the sensory score, the overall score of the pre-fermentation at 15°C was similar to that of the control group, the pre-fermentation at 22°C and 24h had the highest score, the score decreased when the pre-fermentation time reached 36h, and the overall score was the lowest when the pre-fermentation temperature reached 30°C. This is because the excessively high pre-fermentation temperature and long-term fermentation caused excessive reproduction of lactic acid bacteria and other microorganisms, causing the fermentation liquid to be too acidic or produce unpleasant odors. In summary, the pre-fermentation conditions were determined to be 22°C and 24h.

[0036] Example 3 This example is used to illustrate the application of probiotic fermentation in making marinated meat products and the shelf life verification.

[0037] 3.1 Production and quality determination of low-temperature short-shelf-life pickled pepper rabbit The rabbit meat raw material is thawed, cleaned, pickled, pre-cooked and diced, and then cold-soaked by using a traditional process and a fermentation process of the invention.

[0038] Traditional process: prepare soaking liquid according to the proportion of 100 parts of clean water, 12 parts of wild pepper, 2.0 parts of ginger, 0.2 parts of star anise, 0.2 parts of cinnamon, 2.5 parts of salt, 0.4 parts of chicken essence and 1.0 parts of white vinegar; then soak the boiled and cooled raw rabbit meat at a mass ratio of 1:1.2 at 15°C for 24 hours, and then package and store.

[0039] Probiotic fermentation process: The brine preparation process refers to Example 1. After the brine is boiled and cooled, 0.02% of the mass of the brine by Lactobacillus curvatum is added, mixed, and pre-fermented at 22°C for 24 hours; then the boiled and cooled raw rabbit meat is soaked at a ratio of 1:1.2 between the mass ratio of rabbit meat and soaking liquid at 15°C for 24 hours, and then packaged and stored.

[0040] After soaking, the rabbit cubes are vacuum packed. Since low-temperature, short-shelf-life products are not sterilized but stored and sold under cold chain conditions of 4-6°C, after adding probiotics, these products are products with live bacteria and the shelf life does not exceed 7 days. During storage, the changes in the sensory quality of the products and the bag expansion are measured every day to evaluate the shelf life.

[0041] Since the product itself is rich in microorganisms, the total colony count for shelf life determination cannot accurately reflect the test results. Therefore, the shelf life determination is determined by the bag bulging rate and volatile basic nitrogen content. The bag bulging rate is calculated by randomly taking 100 bags of packaged products as a group, storing them in a refrigerator at 4°C for 7 days, and counting the number of bulging bags in each group. Volatile basic nitrogen is determined according to the method of GB 5009.228-2016. The sensory evaluation is conducted by a 10-person evaluation team, who randomly select non-bulging products every day and score them according to the items in Table 4. The test results are shown in Table 5.

[0042] Table 4 Sensory evaluation standards ; Table 5 Shelf life test results .

[0043] The results showed that without any sterilization measures, the traditional process of pickled rabbit meat had bulging or loose bags on the third day, the bulging rate exceeded 10% on the fourth day, and the bulging rate reached 46.7% on the seventh day, and nearly half of the products had bulging or loose bags; while the bulging rate of pickled pepper rabbit meat fermented with probiotics was 8.3% on the seventh day. Judging from the bulging time, the shelf life of pickled pepper rabbit fermented with probiotics was extended by 4 days compared with the traditional process, that is, the shelf life was more than doubled. The test results of volatile basic nitrogen content showed that the TVB-N value of the traditional process was higher than that of the probiotic fermentation group on the first day. With the extension of storage time, the TVB-N of both groups of products increased, but the probiotic fermentation group increased slowly, reaching 1.69 mg / 100g on the seventh day, while the traditional process group increased rapidly from the third day, and rose to 7.88 mg / 100g on the seventh day. The sensory evaluation results showed that the rabbit meat products processed by probiotic fermentation scored higher than those of the traditional process group, and the overall product quality was better.

[0044] 3.2 Preparation and quality determination of pasteurized pickled pepper rabbit The rabbit meat raw material is thawed, cleaned, pickled, pre-cooked and diced, and then cold-soaked by using a traditional process and a fermentation process of the invention.

[0045] Traditional process: prepare soaking liquid according to the proportion of 100 parts of clean water, 12 parts of wild pepper, 2.0 parts of ginger, 0.2 parts of star anise, 0.2 parts of cinnamon, 2.5 parts of salt, 0.4 parts of chicken essence and 1.0 parts of white vinegar; then soak the raw rabbit meat after cooking and cooling at a ratio of 1:1.2 between the mass ratio of rabbit meat and soaking liquid at 15℃ for 24 hours, then vacuum pack it, and pasteurize it at 90℃ for 30 minutes before storing it at room temperature.

[0046] Probiotic fermentation process: After the brine is boiled and cooled, add 0.02% of the brine mass of Lactobacillus curvatum, mix well, and pre-ferment at 22°C for 24 hours; then soak the boiled and cooled raw rabbit meat at a ratio of 1:1.2 between the mass of rabbit meat and soaking liquid at 15°C for 24 hours, then vacuum-pack it, and pasteurize it at 90°C for 30 minutes before storing it at room temperature.

[0047] During the storage period, products from both groups were randomly sampled every 6 days to test the total bacterial count, volatile basic nitrogen content and sensory quality, and the bag expansion rate was calculated to assess the shelf life. The determination method was the same as 3.1. The test results are shown in Table 6.

[0048] Table 6 Shelf life test results .

[0049] The results showed that for the pasteurized products, the traditional process group had bag bulging on the 18th day, and the bag bulging rate exceeded 5% after 30 days of storage, while the pickled pepper rabbit fermented with probiotics had no bag bulging during the storage process. The total colony count test results showed that the traditional process group had microbial proliferation on the 12th day, while the fermentation group detected microorganisms on the 30th day. This is because the microbial flora in the traditional process group products is more complex, and there may be high-temperature resistant microorganisms and microorganisms containing spores, which cannot be completely killed by pasteurization. However, the probiotic fermentation group formed a dominant flora due to the addition of Lactobacillus curvatus, which inhibited the growth of other microorganisms. The selected Lactobacillus curvatus has no spores and is not resistant to high temperatures, so it is easy to kill, making the product have better storage resistance. At the same time, because probiotics inhibit the growth of harmful microorganisms, the bag bulging rate, volatile basic nitrogen content and sensory quality are also much better than traditional processes. In general, when stored at room temperature after pasteurization, the shelf life of pickled rabbit using traditional technology is about 12 days, while the shelf life of products using probiotic fermentation technology can reach 1 month.

[0050] 3.3 Production and quality assessment of irradiated pickled pepper chicken feet The pickled pepper chicken feet were processed by traditional technology and probiotic fermentation technology respectively. The specific technology refers to 3.2. Since chicken feet are not resistant to high temperature, they are sterilized by irradiation according to the current common sterilization method. The only difference from 3.2 is that pasteurization is replaced by irradiation sterilization. After that, they are stored at room temperature of 25°C for 9 months. During this period, the bag expansion rate is counted every month, and the products are randomly selected to test the total colony count, volatile basic nitrogen content and sensory quality, so as to evaluate the shelf life. The determination method is the same as 3.1. The sensory evaluation standards are shown in Table 7, and the test results are shown in Table 8.

[0051] Table 7 Sensory scoring criteria .

[0052] Table 8 Shelf life test results .

[0053] The results showed that the traditional process group of soaked chicken feet sterilized by irradiation had bulging bags in the 7th month, while the soaked chicken feet fermented with probiotics and then irradiated had no bulging bags. The total colony count test results showed that microorganisms were detected in the traditional process group in the 6th month, and microorganisms were detected in the fermentation group in the 7th month, but the product did not bulge. The reason is that Lactobacillus curvatus and Lactobacillus sakei, as dominant bacteria, inhibit the reproduction of other microorganisms, and both bacteria have no spores and do not produce gas, so they are easier to kill. The volatile basic nitrogen content and sensory evaluation results are also far worse than those of products fermented with probiotics. Overall, for soaked chicken feet products stored at room temperature after irradiation sterilization, the shelf life of products under traditional processes is about 6 months, and the shelf life of products under probiotic fermentation process can reach 9 months.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a marinated meat product, characterized in that: Include: After boiling and cooling the brine, add Lactobacillus curvatum and mix evenly to obtain a fermented soaking liquid; The raw meat is boiled and cooled, and then added into the fermentation soaking liquid for soaking, packaging and storage; Among them, the inoculation amount of Lactobacillus curvatus is 0.01~0.04% of the mass of the braising soup.

2. The preparation method according to claim 1, characterized in that The raw materials of the braising soup include, by weight, 100 parts of clear water, 10-15 parts of wild pepper, 1.5-2.5 parts of ginger, 0.2-0.5 parts of star anise, 0.2-0.5 parts of cinnamon, 2.5-3.5 parts of salt, 0.4-0.8 parts of chicken essence, and 1.0-2.0 parts of white vinegar.

3. The preparation method according to claim 1, characterized in that: The brewing process comprises soaking for 20 to 24 hours at 8 to 15°C.

4. The preparation method according to claim 1, characterized in that: The mass ratio of raw meat to fermentation soaking liquid is 1:1~1.

5.

5. The preparation method according to claim 1, characterized in that: The raw meat is divided before soaking.

6. The preparation method according to claim 1, characterized in that: If the packaged product has not been sterilized, it should be stored in a refrigerator at 4-6°C; if the packaged product has been sterilized, it should be stored at room temperature.

7. The preparation method according to claim 1, characterized in that: The composite bacteria were added and pre-fermented at 22° C. for 24 hours to obtain a fermented soaking liquid.

8. A marinated meat product obtained by the preparation method according to any one of claims 1 to 6.