Summary of the hottest irradiation preserved meat

A review of irradiated preserved meat food (Part I)

as early as 1921, Schwartz, B. first proposed that X-ray could be used to kill Trichinella spiralis in meat products in the United States, and obtained a patent. In 1943, hamburgers were irradiated in the United States, marking the birth of irradiated food. In the mid-1950s, the UK, which is the most likely problem for entrepreneurship in the 23 tier cities, France, the Netherlands, Denmark, West Germany, Japan, Canada, the Soviet Union and other 33 countries successively conducted a large number of studies on irradiated food. Until August, 1985, 31 countries and relevant organizations in the world had approved 76 kinds of irradiated food for human consumption, of which 14 countries had approved to irradiate meat food with an irradiation dose of more than 5kGy. The research on food irradiation in China began in 1958. The Ministry of health has approved seven kinds of irradiated food to be sold as commodities, and sausage (sausage) is one of them

irradiation preservation of food is an important aspect of the peaceful use of atomic energy. It is a new method for preserving food. Compared with low-temperature preservation, chemical preservation, modified atmosphere preservation, drying preservation, salting preservation, sealed heating preservation, it has obvious advantages, mainly in the following five aspects: (1) during irradiation of meat food, the radiation can pass through the packaging and freezing layer, killing the microorganisms on the surface and inside of meat food Pests and parasites. Since irradiation is carried out after packaging, irradiated food can also avoid secondary pollution in the process of storage, transportation and marketing; (2) Under the condition of appropriate irradiation dose, the nutritional composition of food does not change significantly, and the degree of preservation is very high; (3) Irradiation preservation can reduce the pressure of refrigeration and save energy. Compared with freezing treatment, irradiation treatment of meat can save 25 ~ 40% energy; (4) Irradiation processing can improve the quality of meat food, such as tenderizing beef; (5) Irradiation preservation was used to prolong the shelf life of meat products. Under the recommended dosage and the condition of vacuum packaging with plastic film, the storage period of irradiated smoked and boiled (pig, cow) breast ribs, small steak and sausage is 3 times longer than that of non irradiated foods. It can be seen that the advantages of irradiation preservation of meat food, he said, are also the reason why many scientists attach great importance to it. Due to the limitation of the technological development level and the speed of energy construction, many foods in China are wasted in 228 (2) 010 metal material tensile tests due to improper preservation. It can be predicted that with the development of atomic energy industry, irradiation instruments as a new method of food processing and storage have broad development prospects

I. sterilization and insecticidal treatment of meat products

(I) irradiation sterilization

minck and Prescott discovered the sterilization effect of ionizing radiation in 1896 and 1902 respectively. The killing effect of X-rays not only directly destroys the DNA in the nucleus of microorganisms, but also produces active particles that have a strong killing effect on bacteria. Irradiation has been used to preserve meat and its products since the early 1950s. Due to different irradiation objects, three different irradiation doses can be adopted to achieve the sterilization purpose we require

1. Selective irradiation sterilization: when the irradiation dose is 1kGy, it can inhibit the growth and reproduction of spoilage microorganisms and increase the period of frozen storage. It is mainly used for the storage and transportation of meat and aquatic products. Pseudomonas sp. in meat and aquatic products has very weak anti irradiation ability. Only 0.048kgy irradiation dose can inhibit its growth, reproduction and even kill it

2. Targeted irradiation sterilization: the irradiation dose of 1-10kgy can kill the non spore producing pathogenic bacteria (such as Salmonella) in food, reduce microbial pollution and prolong the storage period. This dosage is mainly used for retail fresh meat and its products of livestock and poultry. Salmonella contamination often causes food poisoning. Salmonella can increase the bacterial infection of cooked meat (such as chicken and meat) from 105 bacteria/g to 107 bacteria/g within a few hours at a suitable temperature. Salmonella is heat-resistant, and the current heating method can not completely solve the problem of Salmonella contamination in meat food. However, Salmonella is very sensitive to irradiation. A dose of 5kGy can kill 105-7 Salmonella/g food. Irradiation of fresh meat and poultry at the dose of 3 ~ 5kGy can reduce the colony units of gram-negative psychrophilic bacilli that affect the quality of low-temperature preservation to 1/100000. The frozen chicken treated with 8kGy had no obvious change in color, flavor and texture after being stored at - 30 ℃ for two years

in recent years, China has made an in-depth study on the irradiation coating of sausage. 5kGy dose can kill spoilage and pathogenic microorganisms during sausage processing and storage, such as Escherichia coli, mold, Salmonella and Staphylococcus

3. Complete sterilization by irradiation: under the irradiation dose of 10-50kgy, all microorganisms except bacillus can be killed. If the package is not damaged, the irradiated food can be stored for several years at room temperature. This dose is mainly used for meat to resist the irradiation of more uncertain foods in the low tide of chemical industry. The most radiation resistant bacterium in meat food is Botox. The dose required to reduce the spore count of Botox from 1012 to 100 was set as the minimum dose and recorded as D12. Table 1 lists the D12 values for several kinds of meat and their products

Table 1 d12

meat food

d12 (kGy)

meat food

d12 (kGy)

pork

43.7

salted pork

25.2