CN103636739A - CO-containing modified atmosphere packaging freshness-keeping method for chilled fresh pork - Google Patents

Abstract

The invention relates to a fresh-keeping method of modified atmosphere packaging containing CO for chilled fresh pork. After 24 hours of deacidification, the chilled fresh pork is divided into meat pieces weighing about 200g to 250g, and each piece of meat is put into a tray packaging box. Carry out modified atmosphere packaging, in modified atmosphere packaging: the gas composition and volume ratio are: 0.4%CO+30%CO ₂ +69.6%N ₂ , the ratio of the height of the upper space to the thickness of the meat piece is 1.5:1. After packaging, the storage temperature is 0-4°C. The invention prolongs the shelf life of chilled fresh pork under refrigerated conditions (0-4°C) from 4 days in the original aerobic storage mode to more than 20 days, and significantly improves the redness and brightness of the product during storage. Improved color quality.

Description

A CO2-containing modified atmosphere packaging preservation method for chilled fresh pork

(1) Technical field

The invention relates to a CO-containing modified atmosphere packaging preservation method for chilled fresh pork, belonging to the field of preservation of meat and meat products. the

(2) Background technology

With the improvement of people's living standards, the change of consumption concept and the continuous improvement of the cold chain, chilled meat has become more and more favored by consumers. Compared with frozen meat, chilled meat can well maintain the original quality and tissue state, avoiding the loss of juice and quality deterioration of frozen meat during thawing. However, under low-temperature refrigeration conditions, chilled fresh meat is easily spoiled, has a short shelf life, serious juice loss, and serious safety problems, which have severely limited its industrialization and marketization. Therefore, it will be of great economic significance to develop the fresh-keeping technology of chilled pork, prolong the shelf life of products, and reduce the loss of enterprises. the

At present, the commonly used packaging methods for chilled fresh pork include vacuum packaging and ordinary aerobic tray packaging. Vacuum packaging can effectively prolong the shelf life of chilled fresh pork, but in this packaging method, the air in the packaging bag has been drawn out, and the myoglobin in the meat is in a reduced state, making the meat appear purple, and it often needs to be colored before being displayed on the shelf . Moreover, if the oxygen removal is not complete during the packaging process, it will lead to irreparable deterioration of the flesh color. Simultaneously, this packaging method also has the problem of high juice loss. Ordinary aerobic tray packaging is currently a common packaging method for displaying and selling small cut meat in supermarkets. This packaging method is simple and convenient, but microorganisms grow faster under refrigerated conditions, and the shelf life of products is shorter. Under refrigerated conditions, the shelf life of chilled meat packaged in ordinary trays is only 4 to 7 days. In addition to the above two packaging methods, there are still a large amount of chilled pork in chain stores or supermarkets that are retailed in a naked state in my country at present. This sales status makes the meat directly in contact with the external environment, which increases the channels of microbial contamination, makes the meat more prone to microbial contamination, and results in a shorter shelf life for chilled fresh meat. At the same time, the naked sales state can easily make consumers feel extremely unhygienic about the product. the

(3) Contents of the invention

In order to solve the problems of short shelf life and unsatisfactory sales status of chilled pork, the present invention provides a CO-containing modified atmosphere fresh-keeping packaging method for chilled pork. In the present invention, after 24 hours of deacidification, the cold fresh pork is directly divided into modified atmosphere packaging. After a large number of experiments, the reasonable and effective gas composition and gas ratio of modified atmosphere packaging are determined. Combined with tray packaging and low-temperature refrigeration, this technology significantly prolongs the The shelf life of chilled fresh pork is improved, and the color quality of the product shelf life is improved, and the loss of juice is reduced. the

The carbon monoxide gas in the CO-containing modified atmosphere packaging of the present invention can be firmly combined with the main pigment protein myoglobin in the meat to form carboxymyoglobin, which makes the chilled meat produce an attractive cherry red color and maintains a stable color during the shelf life The cherry color does not cause fat oxidation in the meat, which significantly improves the defect of dull color of chilled meat during sales. the

The present invention is realized through the following steps:

After 24 hours of deacidification, the chilled fresh pork is divided into meat pieces weighing about 200g~250g, and each piece of meat is placed in a pallet box for modified atmosphere packaging. In the modified atmosphere packaging: the gas composition and volume ratio are: 0.4 %CO+30%CO ₂ +69.6% N ₂ , the ratio of the height of the upper space to the thickness of the meat piece is 1.5:1; after packaging, the storage temperature is 0-4°C.

The present invention has the following advantages:

1 The shelf life of chilled fresh pork under refrigerated conditions (0-4°C) is significantly extended from 4 days under the original aerobic storage method to more than 20 days;

2 Significantly improved the color quality of chilled fresh pork during the shelf life, and improved the redness value of the product;

3 Reduced juice loss during storage;

4 This fresh-keeping technology has determined a modified atmosphere fresh-keeping packaging method that can not only protect the meat color well, but also significantly prolong the shelf life of cold fresh pork. The exhibition and sale of fresh meat provides a better sales status and a feasible, convenient, hygienic and safe sales method. the

The present invention takes chilled pork as the research object, and finally obtains the best mixed gas parameters of CO-containing modified atmosphere packaging through a large number of experiments, and compares and analyzes the CO modified atmosphere packaging method under this parameter with ordinary aerobic tray packaging, vacuum packaging, etc. The fresh-keeping effect of packaging and high-oxygen modified packaging, found that the CO modified atmosphere packaging method under this parameter can significantly prolong the shelf life of chilled pork, significantly improve the color quality, and effectively improve the safety of chilled pork during the shelf life , enhance consumers' desire to buy. The method changes the traditional sales state of the cold fresh pork exposed in the exhibition and sales refrigerator, provides a better sales state for the exhibition and sales of the cold fresh pork, and provides a feasible, convenient, hygienic and safe sales method. the

(4) Description of the drawings:

Figure 1 Effects of different packaging methods on the total number of bacterial colonies in chilled pork during storage

In the picture: CK: ordinary aerobic pallet packaging, CO: modified atmosphere packaging with CO (0.4%CO+30%CO ₂ +69.6%N ₂ ), VP: vacuum packaging;

It shows that CO-containing modified atmosphere packaging can significantly reduce the total number of colonies of chilled pork during storage, greatly prolong the lag period of microbial growth, and significantly prolong the shelf life. The total colony level of chilled pork in tray packs reached 10 ⁶ cfu/g at 4-8 days, reaching spoilage levels; the total colony counts of vacuum-packed chilled pork did not reach 10 ⁶ cfu/g until days 12-16 , reaching the level of corruption. However, the total number of bacterial colonies in the chilled pork packaged with carbon monoxide modified atmosphere did not reach 10 ⁶ cfu/g until 20-26 days, reaching the spoilage level. Compared with ordinary aerobic tray packaging and vacuum packaging, carbon monoxide modified atmosphere packaging significantly inhibited the growth of microorganisms in chilled pork and effectively extended the shelf life of the product.

Figure 2 The effect of different packaging methods on the volatile basic nitrogen of chilled pork during storage

In the picture: CK: Ordinary aerobic pallet packaging, CO: Modified atmosphere packaging with CO (0.4%CO+30%CO ₂ +69.6%N ₂ ), VP: Vacuum packaging

The changes of volatile basic nitrogen content of chilled pork under the three packaging methods are shown in Figure 2. Both CO-containing modified atmosphere packaging and vacuum packaging significantly inhibited the production of volatile basic nitrogen. Less volatile base nitrogen is produced under packaging. the

(5) Specific implementation methods

Example 1

This embodiment takes the CO modified atmosphere preservation of chilled fresh pork as an example:

The tray packaging box used in this example is the TQBC-0775 box produced by Sealed Air Corporation of ^the United States, with a size of 224mm*133mm*40mm; Transmittance≤15g/24h, m ² (38°C, 90%RH). The plastic packaging film used is Lid1050/550 Lidstock film produced by Sealed Air, USA, with a film thickness of 1.0 mil; the main material is linear low-density polyethylene; tensile strength (1000psi): longitudinal 14.7, transverse 13.0; oxygen permeability (ml/24 hours, m ² ): less than 20.0 at 40, ℉100%RH, less than 6.0 at 40, ℉0%RH, less than 5.0 at 73, ℉0%RH; water vapor permeation Rate≤1.0g/24h,m ² (40, ℉100%RH); recommended temperature 90～60℉. The modified atmosphere packaging machine model is Dajiang Machinery DT-6D.

The modified atmosphere fresh-keeping packaging process for chilled fresh pork is as follows:

Cool the pork (after 24 hours of deacidification) → divide (15cm*10cm*1.5cm, weighing about 200g-250g) → carry out modified atmosphere packaging → store at low temperature (0-4°C). the

After 24 hours of deacidification, the cold fresh pork is directly divided into 15cm*10cm*1.5cm meat pieces weighing about 200g-250g, and each piece of meat is placed in a linear low-density polyethylene box with a size of 224mm*133mm*40mm For modified atmosphere packaging, the optimized gas composition and volume ratio of modified atmosphere packaging are: 0.4%CO+30%CO ₂ +69.6%N ₂ , the ratio of the height of the upper space to the thickness of the meat piece is 1.5:1; The vacuum time is 8.0s, the sealing time is 1.5s, the deflation time is 1.5s, the upper inflation time is 1.4s, the lower inflation time is 1.0s, and the film winding length is 200mm. After packaging, the storage temperature is 0-4°C.

After packaging with this modified atmosphere preservation technology, the total number of colonies of chilled pork can be controlled at 4.90Lgcfu/g when refrigerated for 20 days, and the total nitrogen content of volatile bases in meat can be controlled below 11.09mg/100g. The shelf life of pork has been increased from the original 4 days to more than 20 days, significantly extending the shelf life. On the 12th day, the redness value of the chilled fresh pork (pork tenderloin) packaged in modified atmosphere reached 15.84, which was 51.68 higher than that of ordinary tray packaging; the brightness value reached 52.35, which was 7.25% higher than that of ordinary tray packaging (see Table 1), The loss of stored juice reached 2.41%, which was 26% lower than that of ordinary tray packaging. Therefore, this technology significantly prolongs the shelf life of chilled fresh pork, and significantly improves the color quality and water retention performance of chilled fresh pork during the shelf life. the

Table 1 Effects of different packaging methods on meat color of chilled fresh pork during refrigeration (4°C)

Different letters in the same column indicate significant difference (P<0.05). --- Indicates that the meat is completely spoiled, and no data was obtained. the

Compared with ordinary aerobic tray packaging and vacuum packaging, carbon monoxide modified atmosphere packaging has significantly improved the brightness and redness of the product, especially for red. the

Chilled pork was packaged in three different packaging methods: (1) aerobic tray packaging (CK), (2) vacuum packaging (VP) and (3) CO-containing modified atmosphere packaging (0.4%CO+30%CO ₂ +69.6%N ₂ ).

When stored for 16 days, the shelf life of the tray packaging has exceeded the shelf life, the vacuum packaging has reached the shelf life, and the modified atmosphere packaging containing CO has not yet reached the shelf life, and the meat color is still very good. the

Based on the above results, CO modified atmosphere packaging has the best preservation effect on chilled fresh pork, which not only achieves the purpose of extending the shelf life, but also improves the color and luster quality of pork during storage, and changes the traditional cold fresh pork exposed in the display freezer. The sales status provides a feasible, convenient, hygienic and safe sales method for retail or counter sales of chilled fresh pork. the

Claims (1)

1. a cold fresh pork containing CO controlled atmospheric packing preservation method, it is characterized in that: by cold fresh pork through acid discharge in 24 hours, be divided into the cube meat of heavy 200g～250g, each cube meat is put into a pallet packing box and carry out controlled atmospheric packing, in controlled atmospheric packing: gas componant and volume ratio are: 0.4%CO+30%CO ₂+ 69.6%N ₂, the ratio of upper space height and cube meat thickness is 1.5:1.

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