目的 研究淀粉酶型时间-温度指示剂( TTI) 及酶经固定化后体系稳定性。 方法 以淀粉酶反应体系为基础,确定在时间为 4 ~ 5 d 内,温度为 4 ℃ 的条件下指示剂最佳配比,再应用固定化酶技术,观察固定化酶的凝固性,测定其酶活性能以及应用于 TTI 中的吸光值随时间变化曲线。 结果 确定了淀粉酶型 TTI 体系配方,酶经固定后酶活有所下降,但吸光值变化更平稳。 结论 得到了应用于 4℃ 时的时间-温度指示剂最佳酶固定化条件,以糊精( 质量浓度为 40 g / L) 和碘( 质量分数为 0 . 1% ) 为底物,琼脂固定化酶液( 质量分数为 3% ) 为反应物,该条件下得到最适 pH 值为 6 . 0 , 最适温度为 55℃ ,此时指示剂稳定性最佳,体系颜色变化与时间最理想。

Objective To explore amylase time-temperature indicator( TTI) and its stability properties with the immobilized enzyme. Methods Based on the reaction of amylase, the optimal formula of the indicator at 4 ℃ and within 4 ~ 5 d was determined. After the employment of enzyme immobilization technology, the coagulation was observed, the enzyme activity and the absorbance value change with time curve when it was applied in TTI were analyzed. Results TTI formula was determined, and the activity decreased after the amylase was immobilized, but the absorbance value changed more smoothly. Conclusion The best formula applied to TTI at 4 ℃ was using 40 g / L malt batter and 0. 1% Iodine as the substrates, 3% agar immobilization enzyme solution as reactant, with the optimal pH value and temperature of 6. 0 and 55 ℃ , respectively. In this case, the highest stability and the optimal time and color changes were achieved.