Study On Nitrite And Quality Control Technology In Chicken Meat Curing Process

Curing is a critical process for the deep processing of poultry products.Nitrate in water enters poultry during curing process,and generates nitrite under the action of ni-trate reducing bacteria and reduced enzyme.Nitrite can combine with secondary amine to form nitrosamine at high temperature such as frying and cooking,which poses a threat to human health.Therefore,controlling the amount of nitrite generated during curing is an important aspect to improve the food safety level of poultry products.Roast chicken was used as the research object in this thesis,to analyze nitrite production and dynamic changes during the curing process,and explore the nitrite control and quality improve-ment technology to provide a certain technical basis for improving the quality and food safety level of poultry products.The findings are as follows:Firstly,the results showed that nitrite can be produced spontaneously in the process of chicken soaking and curing,the nitrite content increased first and then decreased with the extension of storage time.The results showed that the initial production of nitrite was lower and the days of peak value appeared later when the curing temperature was lower and the curing time was shorter.The concentration of salt and sugar in the pickling solu-tion can not only affect the taste of meat,but also affect the formation and dynamic trend of nitrite to a certain extent.The higher osmotic pressure produced by higher salt concen-tration and sugar concentration can decrease the growth and reproduction rate of nitrate reducing bacteria,then slow down the formation of nitrite and prolong the appearance time of nitrite peak.Secondly,the active substances in garlic powder and ginger powder effectively re-duce the content of volatile basic nitrogen and nitrite.The more water and salt added,the slower microbial growth.The optimal formula of curing solution was optimized by or-thogonal experiment with garlic powder of 2.0%,ginger powder of 2.5%,nisin of 0.2g/kg,and salt of 4.0%.The results showed that the quality index of the roasted chicken product was significantly improved than that before the optimization,the initial nitrite production was reduced by 87.5%,and the shelf life of the product was extended by 5 days.Thirdly,ultrasonic rapid curing technology can greatly shorten the curing time and improve the quality defects and food safety risks compared to traditional static curing method.The effects of ultrasonic intensity and ultrasonic time on protein oxidation,lipid oxidation,cooking loss,sensory evaluation,nitrite production and shelf-life of chicken were studied.The results showed that ultrasonic curing had a certain oxidation effect on chicken protein.By choosing the appropriate ultrasonic intensity and curing time,the carbonyl content of chicken protein could be controlled at a reasonable level,which was better than the traditional curing method.The ultrasonic curing had no effect on the lipid oxidation and could reduce cooking loss of chicken,it can shorten the curing time,reduce the production of nitrite,and prolong the shelf-life of the products.Compared with the traditional curing method(shelf-life of 7 days),the shelf-life of ultrasonic cured products reached 15 days.However,the ultrasonic curing has a significant impact on the sensory quality of roast chicken.Combined with various indicators,the optimal ultrasonic param-eters were finally determined with ultrasonic intensity of 11.32W/cm~2,ultrasonic time of60min.