竹笋热烫处理过程中颜色变化的动力学模型

Color Change Kinetics of Bamboo Shoot during Blanching

为研究竹笋在热烫处理过程中的颜色变化规律,对竹笋样品分别进行不同温度(80、85、90、95、100℃)、不同时间(3、6、9、12、15、18、21 min)的热烫处理,得到其亮度(L*)值、红绿(a*)值、黄蓝(b*)值的变化规律,并以此为依据计算竹笋总色差(△E)、饱和度、褐变指数(BI)等指标。对这些颜色指标变化分别应用零级、一级反应动力学模型进行拟合分析,结果表明:竹笋的L*、a*的反应速率常数(k)随着热烫温度升高而增加趋势,而b*、△E饱和度和BI的k值均随热烫温度升高而呈减小的趋势。拟合回归系数R^2表明零级反应动力学模型更好地描述了竹笋热烫处理过程中颜色的动态变化。

This study was carried out with the aim to investigate the thermal kinetics of color degradation of bamboo shoot during blanching.The effect of blanching temperature(80,85,90,95 and 100 °C) and blanching time(3,6,9,12,15,18 and 21 min) on color change kinetics of bamboo shoot was investigated.The color change was quantified by Hunter Lab values(whiteness/darkness,L*;redness/greenness,a*;and yellowness/blueness,b*).These values were also used for the calculation of total color change(A E),chroma and browning index(BI).As the blanching temperature increase,the rate constants(k) of L* and a* values tended to be higher,while the rate constants(k) of yellow color,A E,chroma and BI values decreased.These values were significantly changed at higher blanching temperature.The change of color values could be fitted well with a zero-order model.Based on the R2 value of the model,the zero-order model could provide a better explanation of the color change kinetics of bamboo shoot during blanching.