The Effect Of Temperature On Growth Of Clostridium Perfringens In The Sauce And Meat Products

Clostridium perfringens is widely distributed in nature and is a foodborne pathogen.It can produce spores that are resistant to heat.Normal cooking conditions do not inactivate Clostridium perfringens spores.In contrast,cooking activates the spores.During the cooling and storage,the spores germinate,grow and reproduce.?High doses of Clostridium perfringens can cause diarrhea and abdominal cramps.The food poisoning caused by Clostridium perfringens is related to meat and meat products.Based on the? hazards of Clostridium perfringens and the lack of research,the spore production ability of different Clostridium perfringens strains was compared.Then the number of Clostridium perfringens in different cooling time was studied in the medium of roast chicken and sauced beef,which were representative of Chinese sauce and brine meat.Finally,the growth and changes of Clostridium perfringens in different storage temperatures were studied.The study provides a scientific basis for standardizing the production and processing of Chinese sauce and brine meat.The study can reduce the risk of Clostridium perfringens in meat product,ensure the quality of meat products and improve their edible safety.The main research results are as follows:(1)The spore-producing ability of Clostridium perfringens strains from different sources and the effects of different inoculation conditions on the growth of Clostridium perfringens were compared.The results showed that the strains isolated from actual meat products were more likely to produce spores.The effects of different inoculation conditions on the growth of Clostridium perfringens during the cooling process of roast chicken were significantly different;(2)The spores of Clostridium perfringens were inoculated into roast chicken and sauced beef.During the cooling from 55 °C to 4 °C,the cooling time had a significant effect on the growth of Clostridium perfringens in roast chicken and sauced beef.When the cooling time was less than 4 h,there was no significant difference in colony number of Clostridium perfringens before and after cooling.The relative growth before and after cooling is 0.6 log(CFU/g),which is a safe cooling method.The relative growth before and after cooling within 7 h is 1 log(CFU/g),and the colony number after cooling fluctuates at 105 CFU/g,so the cooling time should be less than 7 h to ensure the safety of the product better.It is suggested that the cooling time of the meat products should be controlled within 4 h,the cooling time should not exceed 7 h,and the relative growth before and after cooling should be controlled within 1 log(CFU/g);(3)The growth of Clostridium perfringens in roast chicken and sauced beef were studied at different fluctuation storage temperatures(4? ?,6? ?,8? ?,10? ?,12? ?,15? ?,20? ?,25? ?,30? ?,35? ?)and constant temperature 20? ?.When the storage temperature of roast chicken and sauced beef fluctuates mainly at 25?,30? and 35?,the delay period was short,which was not conducive to product storage,and the growth of Clostridium perfringens changed rapidly when the storage temperature fluctuated at high and low temperatures.But the delay period is long when the storage temperature is below 10 ? in the low temperature region,which is favorable for product storage.Therefore,it is suggested that the meat products should be kept below 10 ? during cold chain storage,and the fluctuation of high and low temperature during storage should be avoided.