包子馅玻璃化转变温度的测定以及货架期的预测

Determination of glass transition temperature and shelf-life prediction of stuffed buns

在低于玻璃化转变温度下贮存食品时可以提高其质量。利用差示扫描热量法(DSC)对包子馅(鸡肉)的玻璃化转变温度进行测定,测得结果为-18.52℃。在不同贮藏温度(4、7、15℃)下对鸡肉馅的挥发性盐基氮、细菌总数、色差、pH值、水分含量、感官评价指标进行检测,结果表明:随贮藏时间的延长挥发性盐基氮和细菌总数逐渐上升,L*值、a*值、b*值、水分含量和感官评分均逐渐降低,pH值呈先升高后降低的趋势。根据Arrhenius方程,以TVB-N和菌落总数作为指标,建立预测包子货架期的动力学模型。得到各指标的活化能Ea和指前因子k0分别为15.868 kJ/mol、56.549 kJ/mol和309.482、1.8×109。

Storing below the glass transition temperature can improve the quality of food. Glass transition temper- ature of stuffing buns （chicken） were measured by using differential scanning calorimetry （DSC） and result was - 18.52℃. Chicken meat stuffing was tested in the area of volatile nitrogen,total bacterial count, color, pH,moisture content, sensory evaluation indicators at different storage temperatures （4,7,15℃）. The results show that： volatile ni- trogen and total bacterial count gradually increased with storage time; L＊ values,a＊ values, b ＊ values, moisture con- tent and sensory scores were gradually reduced; pH value increased first and then decreased. According to Arrhenius equation, using TVB-N and total number of colonies as an indicator, a dynamic model which can predict the shelf life of steamed stuffed bun was establish. The activation energy Ea and pre-exponential factor k0 of each index were 15. 868 kJ/mol,56. 549 kJ/mol and 309. 482,1.8 ×109, respectively.