采用臭氧氧化、可食膜掩蔽、臭氧氧化+可食膜掩蔽3种方法,清除榴莲果肉表面臭味,并利用电子鼻定量检测除臭效果。将密封榴莲果肉样品的系统开0、8、16个小孔,减小榴莲果肉的裸露面积,使榴莲臭味形成3种质量浓度梯度,电子鼻信号曲线能较快地达到平稳状态,用于建立偏最小二乘(partial least squares,PLS)法分析模型。主成分分析表明,3种不同孔数处理后样品的响应值有明显差异;PLS法建立的榴莲果肉臭味气体相对含量模型表明,以榴莲果肉臭味气体相对含量建立的PLS法分析线性拟合曲线的相关系数为0.997,16孔样品的榴莲果肉臭味气体相对含量的平均相对误差小于10%,即电子鼻可以准确地测定榴莲果肉臭味气体的相对含量;硬脂酸膜(膜液质量浓度为硬脂酸2.70 g/L+甘油45.00 g/L+大豆分离蛋白90.00 g/L)掩蔽榴莲臭味的效果最佳;臭氧氧化+可食膜掩蔽方法清除榴莲果肉表面臭味的效果最好。
In this study, ozone oxidation, edible film masking and their combination were applied to eliminate the odor of durian pulp. The effects of these treatments were quantitatively detected by using electronic(E)-nose PEN3. Punching 0, 8 and 16 holes in the samples from three groups reduced respectively the exposed areas of durian pulp to form three odor concentrations. The signal curves of the durian samples used to establish PLS model reached a steady level much faster. The result of principal component analysis(PCA) showed that there were much significant differences between the response values of these three treatments. A model for detecting the relative content of durian pulp odor was established by PLS, and it turned out that the correlation coefficient of the PLS linear fitting curve established on the basis of the relative content of durian pulp odor was 0.997, and that the average relative error for the relative content of the samples with 16 punched holes was lower than 10%, proving that it is feasible to accurately detect the relative content of durian pulp odor by E-nose. The results showed that stearic acid membrane made from 2.70 g of stearic acid, 45.00 g of glycerinum and 90.00 g of SPI in one liter of the mixed liquor was the most effective in masking the odor. The combination of ozone oxidation and edible film masking was the most effective way of eliminating durian pulp odor.