采用挥发性盐基氮动力学模型预测低盐虾酱的货架寿命

Shelf Life Prediction of Low-salt Shrimp Sauce through Kinetic Models of Total Volatile Basic Nitrogen

本文采用挥发性盐基氮(TVB-N)为低盐虾酱的品质变化和货架寿命的指示指标,根据感官评定结果和SB/T 10525-2009,确定TVB-N值4.50 mg/g为货架寿命终点。建立TVB-N与贮藏时间(t)之间的一级动力学方程和TVB-N变化速率常数(k)与贮藏温度(T)之间的Arrhenius方程,以预测在某一贮藏温度下低盐虾酱的货架寿命理论值。求得Arrhenius方程中TVB-N变化反应的活化能Ea为63.69 kJ/moL,指前因子k0为2.76×109,TVB-N的变化速率常数k为2.76×109e-63690/RT。分别在15℃、30℃和37℃条件下验证动力学模型的准确性,得到货架寿命预测值与实际值的相对误差分别为9.79%、7.00%和-6.54%。进一步通过Arrhenius方程外推法求得低盐虾酱在23℃和27℃条件下保藏的理论货架寿命分别为155.8 d和107.2 d,预测结果与实际值之间能较好地符合。

Total volatile basic nitrogen （TVBoN） was selected as the indicator of quality change and shelf life for low-salt shrimp sauce products.The TVB-N was determined to be 4.50 mg/g as the end of shelf life based on sensory evaluation and SB/T 10525-2009. The first order kinetic equation between TVB-N and storage time（t）, and Arrhenius kinetic equation between rate constant of TVB-N（k） and storage temperature （T） were established to predict quality change of low-salt shrimp sauce products and shelf life during storage at a certain temperature. In Arrhenius equation, the activity energy Ea was obtained as 63.69 kJ/moL and pre-exponential factor k0 was 2.76× 10^9. Velocity constant of TVB-N k was 2.76× 10^9^e63690/RX.Compared with observed shelf life of low-salt shrimp sauce products stored at 15,30 and 37 ℃, relative error between predicted and observed shelf life were 9.79%, 7.00% and -6.54%, respectively. Shelf life of low-salt shrimp sauce products was 155.8 days at 23 ℃ and 107.2 days at 27 ℃ through extrapolation of Arrhenius equation, and the predicted results consistent with factual data.