Research On Changes Of Nitrite And Generation Of N-nitrosamine In Cured Minced Meat Under Heat Treated And In Simulated Gastric Juice

The minced meat is one large category of meat product, in order to maintain its colour and lustre and inhibit the growth of microorganism, nitrite is usually used in meat preserved. However, heat treatment proess is one of the most common unit operations. It has important significance that research on change of nitrite and N-nitrosamine in curing minced meat at the condition of heat treatment and simulated gastric juice for preventing harm of nitrite and nitrosamines and guiding people to safety and healthly diet. By now, the study on the occurrence and formation of nitrosamines in meat products and the change of nitrite and N-nitrosamine in simulated gastric juice in domestic and overseas has been limited. Based onthe previous research achievements, this study aims the effect of heat treatment on nitrite and N-nitrosamine in minced meat and change characteristics in simulated gastric juice. The content and results are as follows: the effects of cured, high-pressure cooking, pressure cooking stage and the added amount of sodium nitrite on sodium nitrite residues in cooked minced meat were studied ,and predictive mathematic models of sodium nitrite residues with respect to the added amount of sodium nitrite, cooking time and temperature were developed and certified these models in this paper. The results showed that sodium nitrite residues were highly correlated with the added amount of sodium nitrite and were highly negative correlated with cured time in the cured stage; that sodium nitrite residues were also highly correlated with the added amount of sodium nitrite and were highly negative correlated with cooking temperature and cooking time in the cooking stage. The Kinetic model analysis showed that the impact of high-pressure cooking on descent rate of sodium nitrite residues was more significant than pressure cooking, that sodium nitrite residues were also highly correlated with different temperatures under p<0.01; Coefficient of determination of the above-mentioned models were 0.939, 0.888,; Verification experiment of these models showed that experimental values and regression values had good line, relative error was less than 15%.The effect of heat treatment temperature, heat treatment time and the added amount of sodium nitrite on N-Nitrosodiethylamine (NDEA) in minced meat were studied. The results showed that minced meat don't produce NDEA when heat treatment temperature is below 110℃, and were more likely to produce NDEA when heat treatment temperature is above 110℃and the added amount of sodium nitrite is 150mg/kg.In this experiment, we have studied the change characteristics of the residual nitrite and the formation amounts of nitrosamines in different raw meat component of curing minced meat in the conditions of different heat treatment processings. The results indicate that the residual content of nitrite in the different fat amounts of meat decreases after frying or microwave. At the same of nitrite additives and composition of raw meat, it has significant difference (P < 0.05) between fried processand microwave process on nitrate residua. Under the same condition of heat treatment, the content of residual nitrite in minced meat decreased significantly as fat content increasing (P < 0.05). The proportion of the formation of NDEA increase with increasing the adding amounts of nitrite.Research on nitrite and nitrosamines changing under the condition of simulated gastric juice, the results showed that nitrite decreased significantly (P < 0.01) with digestion time passing under the condition of simulated gastric juice, also the content of nitrosamines appear to decrease with digestion time passing.