‘海沃德’猕猴桃应力松弛特性与品质关系

The Correlation Between the Stress Relaxation Characteristics and the Quality of ‘Haiwode’ Kiwifruit

【目的】提取‘海沃德’猕猴桃的品质特征,建立其应力松弛特性参数与其品质特征的关系,探索一种利用力学特性快速预测猕猴桃品质特征的方法。【方法】测定不同贮藏时期猕猴桃的应力松弛特性、营养成分、色差和质构等指标;运用因子分析筛选出评价猕猴桃品质的特征指标;确定应力松弛的最佳模型,拟合得出模型中的参数;对应力松弛模型参数和猕猴桃品质指标进行相关性分析,利用岭回归法建立应力松弛参数预测猕猴桃品质特征的数学模型,并进行验证。【结果】猕猴桃品质特征指标为VC、可溶性固形物、ΔE、硬度、黏聚性、弹性;七元件麦克斯韦模型可以较好地描述猕猴桃的应力松弛特性,拟合的决定系数达到0.999;VC、可溶性固形物和ΔE与弹性参数和黏性系数有很强的正相关性(P<0.05),其中VC、ΔE与E0的相关系数分别为0.901和0.813,质构指标硬度、弹性和黏聚性与弹性参数和黏性系数正相关性很高(P<0.05),其中硬度与η1相关系数为0.807,弹性与E0的相关系数为0.951;建立的猕猴桃VC、可溶性固形物、ΔE、硬度、黏聚性和弹性的预测模型对建模集的决定系数分别为0.906、0.717、0.883、0.709、0.708和0.851,且均具有统计学意义(P<0.05);模型对验证集的预测值和实测值的决定系数分别为0.882、0.880、0.869、0.691、0.733和0.814,t检验值均小于2.145,表明预测值与实测值之间没有显著性差异。【结论】‘海沃德’猕猴桃的应力松驰特性参数与猕猴桃品质特征具有很强的相关性,运用岭回归法建立的应力松弛参数与各指标的回归模型可以准确地预测猕猴桃的品质特征,为猕猴桃贮藏期间的品质快速测定提供了理论依据。

【Objective】This study aimed to extract the quality properties of Haiwode kiwifruit,and to make further effort to investigate the correlation between its stress relaxation and the quality properties.In addition,a rapid analysis method was considered for quickly predicting the quality properties of kiwifruit by using the mechanical characteristics of kiwifruit.【Method】This study measured the nutrition compositions,color,texture and other indicators of the kiwifruit at the different storage periods,then the factor analysis was applied to select the real quality properties of the kiwifruit,and the model of the stress relaxation was established and the correlation analysis was conducted between the model of stress relaxation and the real quality properties of the kiwifruit.Finally,the mathematical model of stress relaxation predicting the quality features of kiwifruit was obtained by the ridge regression with a final verification.【Result】The Maxwell model with seven components could better describe the stress relaxation of the kiwifruit,and the coefficient of determination of the fit reached 0.999.The Vc,soluble solids andΔE had significantly positive correlation with elastic parameters and viscosity coefficients(P<0.05).Vc and E0,ΔE and E0 had a correlation coefficients of 0.901 and 0.813,respectively.The texture indexes of hardness,elasticity and cohesiveness were also highly correlated with elastic parameters and viscosity coefficients(P<0.05).The correlation coefficients between the hardness andη1,the springiness and E0 were 0.807 and 0.951,respectively.The decision coefficients of the Vc,soluble solids,ΔE,hardness(TPA),cohesion and springiness using in the prediction model were of 0.906,0.717,0.883,0.709,0.708 and 0.851,respectively.And all of them had a great statistical significance(P<0.05).The results show that the decision coefficients between the model predicted values and the measured values to the validation collection were of 0.882,0.880,0.869,0.690,0.733 and 0.814,respectively.The t-test values were all less than 2.145,indicating that there were no significant differences between the predicted values and the measured values.【Conclusion】The results showed that the stress features of the Haiwode kiwifruit were significantly correlated with its quality features.Thus,the mathematical model of stress relaxation constructed by the ridge regression method could accurately predict the quality features of kiwifruit,providing a theoretical basis for the evaluation of the kiwifruit quality during storage period.