热激处理对鲜切莴笋色泽和质地的影响

为探究热激处理对鲜切莴笋色泽和质地的影响,以鲜切莴笋为材料,通过两因素三水平旋转中心组合试验,研究热激处理温度、处理时间对鲜切莴笋a*值、b*值、硬度、脆度、咀嚼性的影响,并在统计分析后,建立二次多项数学模型。结果表明,a*值、硬度、脆度、咀嚼性的回归模型都极显著,b*值不显著;热激处理温度是鲜切莴笋a*值的主要影响因素,处理时间是硬度、脆度、咀嚼性的主要影响因素;鲜切莴笋最佳热激处理条件为:温度49.52℃,时间13.14 min。在此条件下,鲜切莴笋达到最小a*值-12.97,最大硬度40.86 N,最大脆度44.69 N,最大咀嚼性17.96 m J。由此可见,实际应用中可采用处理温度50℃,处理时间14 min得到莴笋净菜良好的色泽和质构。本研究结果为鲜切莴笋热激处理提供了一定的技术依据。

Effect of Heat-shock Treatment on Color and Texture of Fresh-cut Asparagus Lettuces

The effect of the heat-shock treating on the color and texture properties of asparagus lettuces was determined.Central composite design (CCD) was employed to analyze the effect of the heat-shock treating temperature and time on the a* value,b* value,hardness,fracturability and chewiness of asparagus lettuces.Quadratic mathematical model was established after statistical analysis.The results indicated that the regression equations of a* value,hardness,fracturability and chewiness value were significant,but b* value was not significant.The heat-shock treatment temperature was the major influence factor of a* value and the heat-shock treatment time was the major influence factor of firmness,fracturability and chewiness.The optimum heat-shock treatment on asparagus lettuces was under 49.52 ℃ for 13.14 min,under conditions the indexes of a* value,firmness,fracturability and chewiness were-12.97,40.86 N,44.69 N,17.96 mJ,respectively.In practical,relatively favourable colour and textures of asparagus lettuces could be obtained at heat-shock treating temperature of 50 ℃ with treating time of 14 min.The results provided technical supports for the application of heat-shock treatment on fresh-cut asparagus lettuces.