阅读说明：本技术 一种提高肉类初始品质的减菌方法 (Bacteria-reducing method for improving initial quality of meat ) 是由 朱秋劲 白晶 陈玉芹 杨睿颖 龙久铃 黄小艳 陈秀莉 于 2020-12-15 设计创作，主要内容包括：本发明公开了一种提高肉类初始品质的减菌方法,属于食品加工技术领域,具体步骤为：原料肉依次经过紫外光照射30-40min,原料肉质量2％-3％的体积浓度75％的减菌溶液涂抹,原料肉质量的5％-6％的体积浓度2％的乳酸溶液喷洒。本发明采用紫外照射、酒精减菌、乳酸减菌相协同的方法,杀死原料肉表面的微生物,有效降低初始微生物数量的同时还可以通过净化加工环境避免环境对原料造成污染,具有延长货架期、提高初始品质的作用,操作简便、减菌效果显著、安全系数高,本发明为肉类后期加工或贮藏提供良好基础。(The invention discloses a bacteria-reducing method for improving the initial quality of meat, which belongs to the technical field of food processing and comprises the following specific steps: the raw meat is sequentially irradiated by ultraviolet light for 30-40min, the bacteria-reducing solution with the volume concentration of 75% and the mass of 2-3% of the raw meat is smeared, and the lactic acid solution with the volume concentration of 2% and the mass of 5-6% of the raw meat is sprayed. According to the invention, the method of synergy of ultraviolet irradiation, alcohol sterilization and lactic acid sterilization is adopted, microorganisms on the surface of raw meat are killed, the initial microorganism quantity is effectively reduced, the pollution of the environment to the raw material can be avoided by purifying the processing environment, the shelf life is prolonged, the initial quality is improved, the operation is simple and convenient, the sterilization effect is obvious, the safety coefficient is high, and a good foundation is provided for the later-stage processing or storage of meat.)

1. A bacteria reduction method for improving the initial quality of meat is characterized by comprising the following specific steps: irradiating raw meat with ultraviolet light for 30-40min, smearing 75 vol% antibacterial solution, and spraying 2 vol% food grade lactic acid solution;

the using amount of the bacteria-reducing solution is 2-3% of the mass of the raw meat; the using amount of the food-grade lactic acid solution is 5-6% of the mass of the raw meat.

2. An attenuation method according to claim 1, characterized in that: the raw meat is from poultry or livestock.

3. An attenuation method according to claim 1, characterized in that: the power of an ultraviolet lamp of the ultraviolet light is 20W, and the ultraviolet lamp is 30-40cm away from the surface of the raw meat.

4. An attenuation method according to claim 1, characterized in that: the bacteria-reducing solution is prepared by mixing compound alcohol, food-grade glycerol and sterile water.

5. An attenuation method according to claim 4, characterized in that: the volume ratio of the compound alcohol to the food-grade glycerin is 2: 3.

6. An attenuation method according to claim 4 or 5, characterized in that: the compound alcohol is prepared by mixing 52% of grain wine and 95% of edible alcohol.

7. An attenuation method according to claim 6, characterized in that: under the condition that the compound edible alcohol is at 25 ℃, 52 percent of grain wine and 95 percent of edible alcohol are mixed according to the volume ratio of 0.87: 1 is prepared by compounding.

8. An attenuation method according to claim 6, characterized in that: the grain wine is a white wine brewed by taking corn as a raw material.

9. An attenuation method according to claim 7, characterized in that: the grain wine is a white wine brewed by taking corn as a raw material.

Technical Field

The invention relates to the technical field of food processing, in particular to a bacteria reduction method for improving the initial quality of meat.

Background

Pork is selected by most consumers because of rich protein, fat, carbohydrate, calcium, iron, phosphorus and other nutrient components, but is extremely easy to decay under the action of microorganisms and self-derived enzyme oxidation due to the rich nutrient components, so that the edible value is reduced and the economic loss is caused.

With the continuous development of science and technology, a series of food sterilization technologies are developed as soon as the development of times is followed, and the quality of products can be improved by the innovative sterilization technologies such as a low-temperature plasma sterilization technology, a slightly acidic water electrolysis technology, a pulse electric field technology, an irradiation technology and the like, so that the original nutritional value of food is reserved to a greater extent, and the edible quality of the food is improved. However, there are also certain practical problems, such as practical application, that is, the low temperature plasma technology still remains in theoretical research, and no practical production application is yet performed; enterprise cost control, some small and medium-sized enterprises cannot afford the investment of expensive instruments and equipment; lack of professional technicians cannot operate and monitor the test process correctly; the safety problem of the experiment, small and medium-sized enterprises still have certain not enough in the aspect of safety measure protection, can't guarantee the security of production process in the short time.

At present, methods for reducing bacteria and keeping fresh of meat include modes of membrane coating liquid preservation, natural extract bacteriostasis, subacid electrolyzed water reduction, lactic acid reduction and the like. The alcohol coagulates protein in the thallus, destroys bacterial cell walls, and has the function of killing bacteria by enzyme system of microorganism, and research shows that 70-75% of alcohol has the best sterilization effect, and the unique flavor of the alcohol is also applied to remove fishy smell and tenderize the raw meat in the process of pickling the fresh meat, so that the quality of the raw meat is improved, and high-quality products are obtained. However, although an alcohol having an excessively high concentration can rapidly coagulate proteins on the cell surface, a protective film is formed on the cell surface, and the bacteria-reducing effect is reduced. The ignition point of the food grade alcohol is low, the food grade alcohol is diffused in the air, so that the safety accidents such as fire disasters and the like are easily caused, and corresponding measures are taken, so that the effective concentration is reduced by avoiding the volatilization of the alcohol, and the bacteria reducing effect of alcohol can be kept. The food-grade glycerol can be mutually soluble with ethanol, does not influence the sterilization effect of the ethanol to a certain extent, and has the functions of moisture absorption and skin moistening. Lactic acid can reduce the pH of a food system, and secondary metabolites generated in the metabolic process of lactic acid can play a role in bacteriostasis, for example, nisin can inhibit the growth of escherichia coli, listeria monocytogenes and salmonella, so that the effects of bacteriostasis and prolonging the shelf life are achieved, and therefore, lactic acid has higher safety and effective bacteriostasis and fresh-keeping effects, and is widely applied to food. Ultraviolet irradiation is a common sterilization method, and ultraviolet destroys bacteria or viruses by destroying their genetic materials, so that the bacteria or viruses cannot be transcribed and replicated.

At present, a method is needed urgently, namely, on the premise of improving the initial quality of raw meat, a simple, quick, easy-to-operate and high-cost performance bacteria reduction method is adopted, so that the problem of the hygienic quality of the initial quality of the raw meat at present is solved. However, at present, no report on the synergistic bacteria reduction of meat by ultraviolet and alcohol bacteria reduction solution and lactic acid exists.

Disclosure of Invention

The invention aims to provide a bacteria-reducing method for improving the initial quality of pork so as to solve the problems in the prior art.

In order to achieve the purpose, the invention provides the following scheme:

the invention provides a bacteria-reducing method for improving the initial quality of meat, which comprises the following specific steps: irradiating raw meat with ultraviolet light for 30-40min, coating with 75 vol% antibacterial solution, and spraying with 2 vol% food grade lactic acid solution; the using amount of the bacteria-reducing solution is 2-3% of the mass of the raw meat; the consumption of the food-grade lactic acid solution is 5-6% of the mass of the raw meat.

Further, the raw meat is derived from poultry or livestock.

Further, the power of an ultraviolet lamp of the ultraviolet light is 20W, and the ultraviolet lamp is 30-40cm away from the surface of the raw meat.

Further, the bacteria-reducing solution is prepared by mixing compound alcohol, food-grade glycerol and sterile water.

Further, the volume ratio of the compound alcohol to the food-grade glycerin is 2: 3.

Further, under the condition that the compound edible alcohol is at 25 ℃, 52% of grain wine and 95% of edible alcohol are mixed according to the volume ratio of 0.87: 1 is prepared by compounding.

Further, the grain wine is white spirit brewed by taking corn as a raw material.

The invention discloses the following technical effects:

the ultraviolet irradiation sterilization belongs to physical sterilization, does not cause significant influence on the quality of the raw materials, can play a role in purifying and sterilizing the environment where the raw materials are located, and provides a good processing environment for subsequent further production. The ultraviolet lamp has long service life, is easy to operate, and is easy for the safety training of operators. In the process of pickling the fresh meat, the unique flavor of alcohol is also applied to remove fishy smell and tenderize the raw meat, so that the quality of the raw meat is improved, and a high-quality product is obtained. Lactic acid as a green bacteria reducing agent has wide application in the food field, has obvious bacteria reducing effect, and subsequent metabolites such as nisin can inhibit the growth of bacteria and prolong the shelf life of fresh meat. The glycerol has the effects of moisturizing and moistening the skin, can be mutually dissolved with alcohol, plays a certain role in protecting the color of the surface of raw meat, plays the roles of moisturizing and improving the quality when being frequently applied to the processing engineering of pork products, and has the effects of moistening the skin and reducing the stimulation of a bacteria reducer in the antibacterial solution. Therefore, the combination of several bacteria reduction modes can effectively reduce the initial microbial quantity, can avoid the pollution of the environment to the raw materials by purifying the processing environment, and has the effects of prolonging the shelf life and improving the initial quality. Therefore, the bacteria-reducing process has the advantages of strong bacteria-reducing capacity, prolonged shelf life, simple and convenient operation for enterprises and processors, remarkable bacteria-reducing effect and high safety coefficient.

The composite bacteria-reducing process has better effect of reducing bacteria of pork, is more favorable for ensuring the safety of meat products and prolonging the shelf life of commodities, and has the advantages of no pollution, high safety factor, low production cost and obvious economic benefit.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive labor.

FIG. 1 is a schematic view of a green sterilization process;

FIG. 2 is a result of comparing the sterilization rates of examples 1 to 4 with comparative examples 1 to 5;

FIG. 3 is a graph showing the effect of the sequence of the bacteria-reducing process of comparative example 6 on the bacteria-reducing rate, where K is blank, A is UV + bacteria-reducing solution + lactic acid, and B is UV + lactic acid + bacteria-reducing solution.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

Preparing a bacteria-reducing solution under aseptic conditions: a compound alcohol is prepared from 52% grain wine (liquor brewed by taking corn as a raw material and mainly comprising ethanol and water) and 95% edible alcohol, and the compound alcohol, food-grade glycerol and sterile water are mixed according to the volume ratio of 2:3 to prepare a bacteria-reducing solution with the volume concentration of 75%. Under aseptic conditions, food-grade lactic acid is prepared into a lactic acid solution with the volume concentration of 2%. And sealing the bacteria-reducing solution and the lactic acid solution under aseptic conditions for later use.

The raw meat in example 1 was fresh pork ham purchased from a supermarket and slaughtered in the morning.

The raw meat in example 2 was fresh cattle slaughtered in the morning, purchased from a supermarket, with the back facing the long muscles.

The raw material meat in example 3 was fresh lamb hind leg meat purchased from a supermarket and slaughtered in the morning.

The raw meat in example 4 was fresh chicken leg meat which was purchased from a supermarket and slaughtered in the morning.

Example 1 Green bacteria-reducing Process

S1, pretreatment of raw materials: trimming raw meat (pork hind leg meat) with a sterile chopping board and a cutter in a sterile room, removing skin and fascia, and cutting into 30.00 g-sized meat pieces;

s2, ultraviolet sterilization treatment: placing the cut meat blocks in a sterile container, placing in a superclean bench, making the ultraviolet lamp 30cm away from the surface of the meat blocks, and irradiating for 30 min;

s3, smearing the prepared antibacterial solution according to 2% of the mass of the raw meat;

s4, after the sterilization process is completed, spraying the prepared lactic acid solution according to 5% of the mass of the raw meat to obtain the raw meat subjected to sterilization treatment.

The flow diagram of the green bacteria-reducing process is shown in figure 1.

Example 2 Green bacteria-reducing Process

The specific method is the same as example 1, and is different from example 1 only in that the raw meat is beef back-to-long muscle meat, the bacteria-reducing solution is coated according to 3% of the mass of the raw meat, and the lactic acid solution is sprayed according to 6% of the mass of the raw meat.

Example 3 Green bacteria-reducing Process

The specific method is the same as example 1, and is different from example 1 only in that the raw material meat is sheep ham meat, the bacteria reducing solution is coated according to 3% of the mass of the raw material meat, and the lactic acid solution is sprayed according to 6% of the mass of the raw material meat.

Example 4 Green bacteria-reducing Process

The specific method is the same as example 1, and is different from example 1 only in that the raw meat is chicken leg meat, the bacteria reducing solution is coated according to 2% of the mass of the raw meat, and the lactic acid solution is sprayed according to 5% of the mass of the raw meat.

Comparative example 1 influence of ultraviolet irradiation on quality of raw meat (pork ham, beef back to longissimus, lamb ham, chicken ham)

S1, pretreatment of raw materials: trimming each group of raw meat by using a sterile chopping board and a cutter in a sterile room, removing skins and fascia, and cutting into 30.00 g-sized meat blocks;

s2, ultraviolet irradiation treatment: and (5) placing the meat blocks in the step (S1) in an aseptic super clean bench, and carrying out ultraviolet light irradiation and sterilization treatment on the meat blocks for 40min to obtain the meat blocks subjected to sterilization treatment.

Comparative example 275% Effect of the bacteria-reducing solution on the quality of raw meat (pork ham, beef back to longissimus, lamb ham, chicken ham)

S1, pretreatment of raw materials: trimming each group of raw meat by using a sterile chopping board and a cutter in a sterile room, removing skins and fascia, and cutting into 30.00 g-sized meat blocks;

s2, 75% bacteria-reducing solution treatment: after the processing of step S1, the surface of the meat piece is coated with 75% of the bacteria-reduced solution in a sterile super clean bench to obtain the meat piece after the bacteria-reduction processing.

Comparative example influence of 32% lactic acid solution on quality of raw meat (pork hind leg meat, beef back to longmuscle, lamb hind leg meat, chicken leg meat)

S1, pretreatment of raw materials: trimming each group of raw meat by using a sterile chopping board and a cutter in a sterile room, removing skins and fascia, and cutting into 30.00 g-sized meat blocks;

s2, lactic acid solution treatment: after the processing of step S1, a 2% lactic acid solution was applied to the surface of the meat piece in a sterile clean bench.

Comparative example 4 Effect of UV irradiation in combination with 75% by volume of an antimicrobial solution on the quality of raw meat (pork ham, beef back to longissimus, lamb ham, chicken ham)

S1, pretreatment of raw materials: trimming each group of raw meat by using a sterile chopping board and a cutter in a sterile room, removing skins and fascia, and cutting into 30.00 g-sized meat blocks;

s2, ultraviolet irradiation treatment: placing the meat blocks in the step S1 in an aseptic super clean bench, and carrying out ultraviolet irradiation and sterilization treatment on the meat blocks for 30min to obtain the meat blocks subjected to sterilization treatment;

s3, 75% bacteria-reducing solution treatment: after the processing of step S2, the 75% bacteria-reduced solution is applied to the surface of the meat piece in a sterile ultra clean bench.

Comparative example 5 Effect of UV irradiation in combination with lactic acid solution of 2% by volume on the quality of raw meat (pork ham, beef back to longissimus, lamb ham, chicken ham)

S1, pretreatment of raw materials: trimming each group of raw meat by using a sterile chopping board and a cutter in a sterile room, removing skins and fascia, and cutting into 30.00 g-sized meat blocks;

s2, ultraviolet irradiation treatment: placing the meat blocks in the step S1 in an aseptic super clean bench, and carrying out ultraviolet irradiation and sterilization treatment on the meat blocks for 30min to obtain the meat blocks subjected to sterilization treatment;

s3, treatment of the bacteria-reducing solution: after the processing of step S2, a 2% lactic acid solution was applied to the surface of the meat piece in an aseptic ultra clean bench at 5% by mass of the meat piece.

Comparative example 6 comparison of synergistic use of ultraviolet irradiation, lactic acid solution, and sterilizing solution in order with Green sterilizing Process

6.1 treatment of raw meat (pork hind leg meat, beef back to longus muscle, lamb hind leg meat, chicken leg meat) with ultraviolet irradiation, lactic acid solution, and bacteria-reducing solution in this order:

s1, pretreatment of raw materials: trimming each group of raw meat by using a sterile chopping board and a cutter in a sterile room, removing skins and fascia, and cutting into 30.00 g-sized meat blocks;

s2, ultraviolet irradiation treatment: placing the meat blocks in the step S1 in an aseptic super clean bench, and carrying out ultraviolet irradiation and sterilization treatment on the meat blocks for 30min to obtain the meat blocks subjected to sterilization treatment;

s3, lactic acid solution treatment: after the treatment of the step S2, smearing the prepared 2% lactic acid solution on the surface of the meat loaf in an aseptic super clean bench to obtain the meat loaf subjected to the bacteria reduction treatment;

s4, treatment of the bacteria-reducing solution: after the processing of step S3, a 75% sterile solution prepared in advance is applied to the surface of the meat piece in a sterile super clean bench.

6.2 processing raw meat (pig hind leg meat, cattle back to long muscle, sheep hind leg meat, chicken leg meat) by a green bacteria-reducing process:

s1, pretreatment of raw materials: trimming each group of raw meat by using a sterile chopping board and a cutter in a sterile room, removing skins and fascia, and cutting into 30.00 g-sized meat blocks;

s2, ultraviolet irradiation treatment: placing the meat blocks in the step S1 in an aseptic super clean bench, and carrying out ultraviolet irradiation and sterilization treatment on the meat blocks for 30min to obtain the meat blocks subjected to sterilization treatment;

s3, treatment of the bacteria-reducing solution: after the processing of the step S2, smearing the prepared 75% bacteria-reducing solution on the surface of the meat loaf in an aseptic super-clean bench to obtain the meat loaf subjected to bacteria-reducing processing;

s4, lactic acid solution treatment: after the processing of step S3, a 2% lactic acid solution prepared in advance is applied to the surface of the meat piece in a sterile super clean bench.

Test example 1

The untreated blanks, the meat pieces of examples 1-4 and comparative examples 1-6, referred to the pour plate method of GB4789.2-2016, combined with the reduction rate visually showed an improvement in the quality of the raw material by the reduction method.

1. Determination of the germ reduction ratio of a sample of meat pieces

The bacteria reduction rate is determined by pouring the bacteria into a flat plate method according to GB4789.2-2016 food safety national standard food microbiology test colony total number determination. Taking 5g of samples of examples 1-4, comparative examples 1-5 and untreated blank groups in 45mL of sterile physiological saline, beating and homogenizing the samples by a beating machine, taking 1mL of bacterial liquid for dilution, and selecting 10^-3、10^-4、10^-5These 3 dilutions, each timeThree gradients were made in parallel, incubated in a 37 ℃ incubator for 48h and counted. The bacteria reduction effect of the experimental group is visually shown by the bacteria reduction rate. The calculation is carried out according to the following formula:

2. determination of pH value of meat mass

Randomly selecting 3 different parts of each sample, inserting a probe of a pH meter into the sample, closely contacting the sample, and reading a pH value after the number is stable and a prompt tone is given out.

3. Determination of centrifugal loss rate of meat mass

Weighing about 5.00g of block sample with the initial mass of the meat sample being m₁Then wrapping the sample with filter paper, placing the sample in a centrifuge tube, centrifuging the sample at 14 ℃ and 4000r/min for 25min, taking out the sample, stripping off the filter paper, and weighing the meat sample with the mass m₂The calculation is carried out according to the following formula:

in the formula: m is₁Initial mass, m₂Is the meat-like mass after centrifugation.

The pork samples obtained in the examples of the present invention were subjected to the measurement of the bacteria reduction rate, pH, and centrifugal loss rate.

And (3) test results:

(1) as shown in FIG. 2, compared with the blank group, the green sterilization process (examples 1-4) of the present invention can effectively reduce the initial microbial count on the surface of the raw meat, improve the initial quality, and avoid the final quality of the product from being affected by the initial microbial count. Due to the different quality of raw meat among groups in the test process, the same bacteria reduction method has difference among different experimental group data. The raw meat samples of examples 1-4 all had a bacteria reduction rate of over 90% after being treated by the bacteria reduction method.

(2) As a result, as shown in FIG. 2, the effect of the reduction ratio was improved by the combination of UV and two types of the reduction agents, wherein the reduction ratio of the combination of UV and lactic acid was higher than that of the combination of UV and the reduction solution by 12.43% at the maximum.

(3) The pH and the centrifuge loss rate of the green sterilization process examples of examples 1 to 4 are shown in Table 1; the pH and the centrifuge loss ratio of the blank and comparative examples 1 to 5 are shown in Table 2.

TABLE 1 Green Sterilization Process example pH and centrifuge loss Rate

TABLE 2 pH and centrifuge loss rates for blanks and comparative examples 1-5

(4) As shown in fig. 3, the bacteria-reducing effect of the uv + bacteria-reducing solution + lactic acid (green bacteria-reducing process) is better than that of the uv + lactic acid + bacteria-reducing solution by comparing the order of combining the lactic acid solution, the bacteria-reducing solution and the uv. Therefore, in practical production application, the sterilization process sequence of ultraviolet + sterilization solution + lactic acid can be adopted. After Box-Behnken test optimization is carried out on the process, the optimal process parameter combination is selected as follows: the ultraviolet irradiation time is 30min, the usage amount of the bacteria-reducing solution with the volume concentration of 75 percent is 2 to 3 percent, and the usage amount of the lactic acid with the volume concentration of 2 percent is 5 to 6 percent.

In conclusion, the green bacteria-reducing process of the embodiments 1 to 4 is superior to the single-factor and two-factor bacteria-reducing experiments compared with the comparative examples 1 to 6, and the bacteria-reducing effect of the green bacteria-reducing process of the invention is superior to the sequence of the ultraviolet + lactic acid + bacteria-reducing solution. The sterilization method of the green sterilization process is based on the traditional white spirit sterilization process, and the mutual solubility of food-grade glycerol and ethanol is applied, so that the potential safety hazard caused by volatilization of the ethanol is avoided, and the initial quality of the raw meat is further improved on the premise of removing fishy smell and improving the quality of the raw meat; the lactic acid bacteria reduction can not only improve the initial hygiene quality of the raw meat, but also ensure the later quality of the raw meat to a certain extent. Therefore, the green bacteria-reducing process has practical value and application value.

The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.