两种杀菌条件下蓝莓汁储藏品质变化及动力学研究

为了解经热杀菌和微波杀菌后蓝莓汁在不同储藏温度下品质的变化,采用一级反应动力学模型和Arrhenius经验方程,通过分别将热杀菌和微波杀菌所得的蓝莓汁储藏在不同的温度下,研究了储藏期间热杀菌和微波杀菌所得蓝莓汁中菌落总数、花青素含量、色泽的变化规律,并建立了相关动力学模型。结果表明:在储藏期间热杀菌和微波杀菌蓝莓汁中菌落总数、花青素含量、色泽的变化均符合一级反应动力学模型(R2>0.9),并可用Arrhenius方程拟合(R2>0.98);在较低的储藏温度下,蓝莓汁的菌落总数增长缓慢,花青素和色泽的损失较小,蓝莓汁可长时间保持较好的品质;相比热杀菌,微波杀菌能使储藏期间的蓝莓汁更好地保留花青素和色泽,但其保存期相对较短;各模型预测值与实验值之间相对误差均不超过2%,所有模型的预测准确性均较高。

Quality Changes and Kinetics of Thermal and Microwave Processed Blueberry Juice During Storage

The first order reaction kinetics and Arrhenius equation was employed to analyze the effects of storage temperature on total bacterial count,total anthocyanin content and color of blueberry juice,and establish relative kinetics models. The blueberry juice was treated with thermal treatment and microwave treatment,and then stored at different temperatures. The results showed all the changes of total bacterial count,total anthocyanin content and color of blueberry juice accorded with the first order reaction kinetics(R2>0.9),and could be fitted by Arrhenius equation(R2>0.98).At a low storage temperature,total bacterial count increased slowly and little loss was found in total anthocyanins and color,so the blueberry juice could remain good quality for a long time. Compared with thermal sterilization juice,anthocyanins,color and antioxidant activity could remain better inmicrowave sterilization juice grew up a litter faster,but its quality guarantee period was shorter. All the relative errors of the model predicted value and actual value were less than 2%. That indicated all the models were credible.