阅读说明：本技术 小龙虾的微波反压杀菌技术及工艺 (Microwave back pressure sterilization technology and process for crayfishes ) 是由 栾东磊 潘志海 刘宇昊 郭长凯 胡蕾琪 张柔佳 于 2019-11-18 设计创作，主要内容包括：本发明公开了一种小龙虾的微波反压杀菌工艺,包括如下步骤：步骤一,采用新鲜小龙虾,吐污、清洗；步骤二,超声清洗；步骤三,分拣称重分级；步骤四,预煮、装袋；步骤五,袋内注入调味料,并真空包装；步骤六,微波快速升温,0.2Mpa压力下,3分钟内核心温度在达到115-121℃以上；步骤七,121℃保温3-5分钟；步骤八,反压冷却；步骤九,包装出库。对小龙虾进行预热处理,调味,之后采用预包装加工方式,隔绝了二次污染；在利用微波加热快速升温加热,之后进行保温和反压冷却,在防止包装胀袋的前提下提高了杀菌温度；根据杀菌程度可常温或0-4℃贮藏；虾体肉质细嫩,风味好；营养成分保留率高；开袋即食,食用方便。(The invention discloses a microwave back-pressure sterilization process for crayfishes, which comprises the following steps of , using fresh crayfishes, spitting dirt and cleaning, step two, carrying out ultrasonic cleaning, step three, sorting, weighing and grading, step four, pre-boiling, bagging, step five, injecting seasonings into bags, carrying out vacuum packaging, step six, carrying out microwave rapid heating, keeping the core temperature at above 115-121 ℃ within 3 minutes under the pressure of 0.2Mpa, keeping the temperature at 121 ℃ for 3-5 minutes, step eight, carrying out back-pressure cooling, step nine, carrying out packaging and ex-warehouse, carrying out preheating treatment on the crayfishes, seasoning, then adopting a pre-packaging processing mode to isolate secondary pollution, carrying out microwave heating rapid heating, then carrying out heat preservation and back-pressure cooling, improving the sterilization temperature on the premise of preventing bag expansion of the packaging, carrying out storage at normal temperature or 0-4 ℃ according to the sterilization degree, enabling the crayfishes to be tender in meat, good in flavor, high nutrient component retention rate, being ready to eat and being convenient to eat.)

1. The microwave back pressure sterilization process for crayfishes is characterized by comprising the following steps:

step , using fresh crayfish, spitting dirt and cleaning;

step two, ultrasonic cleaning;

step three, sorting, weighing and grading;

step four, precooking and bagging;

step five, injecting seasonings into the bags, and carrying out vacuum packaging;

step six, rapidly raising the temperature by microwave, wherein the core temperature reaches over 115-121 ℃ within 3 minutes;

step seven, keeping the temperature for 3-5 minutes by back pressure;

step eight, back pressure cooling;

and step nine, packaging and delivering out of the warehouse.

2. The microwave back-pressure sterilization process for crayfish as claimed in claim 1, wherein in said step , the fresh crayfish is stood still for 12 hours and then cleaned.

3. The microwave back pressure sterilization process for crayfish as claimed in claim 1, wherein the second step is preceded by preheating to remove the crayfish head and picking out the crayfish threads while leaving only the crayfish tail.

4. The microwave back pressure sterilization process for crayfish as claimed in claim 1, wherein in the third step, the crayfish tails are cleaned by ultrasonic for 20min under the conditions of 300W of power and 28KHz of ultrasonic frequency.

5. The microwave back pressure sterilization process for crayfish as claimed in claim 1, wherein in the third step, the sorting, weighing and grading are carried out according to the weight of the tail of the crayfish.

6. The microwave back pressure sterilization process for crayfish as claimed in claim 1, wherein in the fourth step, the step of bagging comprises putting the crayfish tails into a high temperature resistant cooking bag.

7. The microwave back-pressure sterilization process for crayfishes as claimed in claim 1, wherein in the sixth step, the temperature is rapidly raised by microwave heating under the pressure of 0.2MPa, and the core temperature reaches above 115-121 ℃ within 3 minutes.

8. The microwave back-pressure sterilization process for crayfishes as claimed in claim 1, wherein in the seventh step, the temperature is maintained at 121 ℃ for 3-5 minutes, the pressure is 0.2MPa, and the core temperature is higher than 121 ℃.

9. The microwave back-pressure sterilization process for crayfish according to claim 1, wherein in the eighth step, the back-pressure cooling is back-pressure ice-water bath cooling for 10-15 minutes, and the core temperature is reduced to below 20 ℃.

Technical Field

The invention relates to the field of new food processing technology, in particular to a microwave back pressure sterilization technology and a microwave back pressure sterilization technology for crayfishes.

Background

The crustaceans such as shrimps, crabs and the like have rich nutrition, delicious taste and high proportion of unsaturated fatty acid, and are rich in various amino acids necessary for human bodies, particularly histidine required by infants. Is very popular among consumers due to its unique flavor and diversified cooking methods. In 2017, the breeding yield of the crayfish (procambarus clarkii) in China is 112.97 million tons, the total economic value of the crayfish is 2685 million yuan, and the processing yield is 200 million yuan [ reference: fishery administration in rural areas of agriculture chinese crayfish industry development report [ Z ].2018 ], and is rising year by year.

At present, crayfish is mainly supplied to restaurants and restaurants, mainly cooked in fresh market, and has low processing degree. In addition, the time of the crayfish to market is 5-9 months, wherein a large amount of crayfish is sold in the market in 6-8 months, and if the crayfish cannot be effectively processed, the crayfish quickly dies and decays, so that a large amount of resources are wasted. At present, the crayfish is quick-frozen in a main processing mode, and most manufacturers preserve the crayfish in a liquid nitrogen quick-freezing mode so as to facilitate later processing and consumption. But the refrigeration needs to consume a large amount of energy and has higher cost. In addition, the food needs to be thawed again during consumption, and the food is inconvenient to eat while consuming energy.

Currently, cooked crayfishes are mostly packaged in vacuum after cooking and then preserved in a freezing way, but the following defects exist:

(1) the packaging process is easy to pollute microorganisms after heat treatment;

(2) the freezing storage has high requirements on logistics;

(3) before eating, the food needs to be unfrozen and heated, which is more complicated, and the quality of the unfrozen product is reduced to some extent;

(4) the product has requirements on the eating conditions of the product and can not be eaten instantly after the bag is opened.

The method is characterized in that is the simplest food sterilization method at present, microorganisms are inactivated by heating food, and the food is kept in an aseptic state, and crustacean aquatic products are easy to store dirt and become hotbeds for parasites and microorganism growth, the microorganism content in the crustacean aquatic products is higher, in addition, a plurality of gaps exist in the crustacean aquatic products due to physiological structures, and the heat transfer rate in the heating process is very slow, so that the microorganisms are difficult to completely kill in the traditional heat sterilization mode, and the sensory and nutritional quality of the crayfish are greatly damaged due to long heating time.

Disclosure of Invention

The invention aims to provide a microwave back-pressure sterilization process for crayfishes, and aims to solve the two problems that the shelf life of instant crayfishes is prolonged at , and the high quality of the instant crayfishes is maintained at .

The invention is realized by the following technical scheme:

the microwave back pressure sterilization process for crayfishes comprises the following steps:

step , using fresh crayfish, spitting dirt and cleaning;

step two, ultrasonic cleaning;

step three, sorting, weighing and grading;

step four, pre-cooking, dividing the cooked food into three to five parts, and bagging;

step five, injecting seasonings into the bags, and carrying out vacuum packaging;

step six, rapidly heating by microwave, wherein the core temperature reaches over 115-121 ℃ within 3 minutes;

seventhly, preserving heat for 3-5 minutes at 121 ℃;

step eight, back pressure cooling;

and step nine, packaging and delivering out of the warehouse.

Preferably, in the step , the fresh crayfish is kept still for 12 hours and then spitted and cleaned.

Preferably, the second step is preceded by preheating to remove the head of the crayfish and pick out the crayfish threads, leaving only the tail of the crayfish.

Preferably, in the third step, the shrimp tails are cleaned by ultrasonic for 20min under the conditions of 300W of power and 28KHz of ultrasonic frequency.

Preferably, in the third step, the sorting, weighing and grading are performed according to the weight of the tail and the head of the shrimp.

Preferably, in the fourth step, the bagging is to put the shrimp tails into a high-temperature-resistant cooking bag.

Preferably, in the sixth step, the microwave heating is performed to rapidly raise the temperature, the pressure is 0.2MPa, and the core temperature reaches over 115-121 ℃ within 3 minutes.

Preferably, in the seventh step, the temperature is kept for 3-5 minutes under the condition of back pressure and 0.2MPa, and the core temperature is higher than 121 ℃.

Preferably, in the step eight, the counter-pressure cooling is counter-pressure ice-water bath cooling for 15 minutes, and the core temperature is reduced to below 20 ℃.

The technical principle of the invention is as follows: ultrasonic cleaning is performed by peeling a dirt layer from an adhesion surface by cavitation action, direct current action, or the like of ultrasonic waves in a liquid. Crustacean aquatic products such as crayfish crust texture is comparatively hard, and inside contains a large amount of holes, leads to heat transfer rate very slow, and consequently the tradition is disinfected consuming time and is consumed energy, and bactericidal effect is relatively poor, and is great to the sense organ and the nutritional quality influence of product, and the microwave can penetrate the crust and carry out the direct heating to its inside, and the programming rate is fast, and bactericidal effect is good, can improve its sense organ and nutritional quality when guaranteeing bactericidal effect.

The advantages of the technology are as follows:

(1) carrying out preheating treatment on the crayfish and seasoning. Then, a pre-packaging processing mode is adopted, and secondary pollution is isolated after the packaging process of sterilization treatment;

(2) heating, heat preservation and cooling are carried out under the condition of back pressure, and the sterilization temperature is increased on the premise of preventing package expansion;

(3) the sterilization time is short, the microwave temperature rise is within 3 minutes, the heat preservation is carried out for 3-5 minutes, and the sensory and nutritional quality of the product is high.

(4) The microbial quantity is reduced by 10-12 orders of magnitude (whole shrimp) or 6-10 orders of magnitude (shrimp tail), and design processing is carried out according to the requirement of the product

(5) Can be preserved at normal temperature or 0-4 ℃ according to the sterilization degree. (ii) a

(6) The shrimp meat is tender, the flavor is good, and the retention rate of nutrient components is high;

(7) the product can be eaten after opening the bag and is convenient to eat.

Drawings

Fig. 1 is a flow chart of a sterilization process for crayfish according to embodiments of the invention.

Fig. 2 is a schematic view of the sterilization principle of crayfishes according to the embodiment of the invention.

Fig. 3 is a comparison graph of shelf life before and after microwave sterilization of crayfish (including fig. 3a, 3b, and 3c) according to the present invention.

Detailed Description

The embodiments of the present invention will be described in detail below with reference to the accompanying drawings: the present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.

As shown in figure 1, the microwave back pressure sterilization process for crayfish comprises the following steps:

and , spitting dirt, cleaning, and simply cleaning the fresh crayfish after the fresh crayfish is kept for 12 hours.

And step two, preheating to remove the head of the crayfish, picking out the crayfish threads and only keeping the tail part of the crayfish.

And step three, ultrasonic cleaning. And ultrasonically cleaning the shrimp tails for 20min under the conditions of 300W of power and 28KHz of ultrasonic frequency.

And step four, sorting, weighing and grading, and classifying according to the weight of each shrimp tail head.

And step five, filling the shrimp tails into a high-temperature-resistant cooking bag.

And step six, injecting feed liquid into the cooking bag, vacuumizing and sealing.

And step seven, heating by microwave back pressure, wherein the pressure is 0.2MPa, and the core temperature is more than 115-121 ℃.

And step eight, preserving the heat for 3-5 minutes, wherein the core temperature is higher than 121 ℃.

And step nine, cooling the mixture in ice-water bath under back pressure for 15 minutes, and reducing the core temperature to be below 20 ℃.

And step ten, packaging and delivering out of the warehouse.

As shown in figure 2, fresh crayfish is heated by a microwave source, the core temperature is increased to 115-121 ℃ under the pressure of 0.2MPa, then heat preservation is carried out, the core temperature is higher than 121 ℃, then counter-pressure ice-water bath cooling is carried out for 15 minutes, the core temperature is reduced to below 20 ℃, and finally cooked crayfish is obtained.

As shown in FIG. 3, FIG. 3a is a photograph of a crayfish after being washed and vacuum packed; FIG. 3b is a photograph of a crayfish undergoing microwave sterilization; after being treated by 6 number-level microbe with reduced sterilization intensity and being refrigerated at 4 ℃ for 30 days, no obvious phenomena of bag expansion deterioration and peculiar smell are found; FIG. 3c is a photograph of a crayfish that has not been sterilized, and that has been significantly deteriorated by swelling after being refrigerated at 4 ℃ for 3 days, accompanied by a strong foul smell.

The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.