以拉曼光谱技术结合化学计量学方法实现两类不同成熟度的双孢菇菌盖硬度的建模预测分析。将菌盖直径平均值2~3 cm的样品划为Ⅰ类成熟度, 3~5 cm为Ⅱ类。对两类样品分别取65个进行光谱采集并测量硬度, 分别采用标准正态变量变换、基线校正、一阶导数、二阶导数4种方法预处理, 建立偏最小二乘模型(PLS)。比较模型效果得出最佳预处理方法均为一阶导, 但Ⅰ类建模的预测相关系数(Rp)和均方根误差(RMSEP)分别为0.887和0.444, Ⅱ类的Rp和RMSEP分别为0.896和0.435。结果表明Ⅱ类成熟度蘑菇的硬度预测比Ⅰ类更为准确, 在同等条件下, Ⅱ类蘑菇硬度的变化更可准确预测, 其贮藏保鲜更有规律可循。

The firmness model of agaricus bisporus pileus was established by using Raman spectroscopy combined with chemometric methods. With the help of PinPoniterTM portable Raman spectrometer, rapid and nondestructive for agaricus bisporus firmness prediction was studied. According to the average pileus diameter, the samples with pileus diameter of 2-3 cm were classified as class Ⅰ maturity, 3-5 cm as class Ⅱ. 65 samples of each type were used to collect spectrum and measure firmness. The data were pretreated by four methods of 1st derivatives, 2nd derivatives, standard normal variate and baseline, respectively. The model of partial least square was established. The best effect of both model was 1st derivative, but the correlation coefficient (Rp) and root mean square error of prediction (RMSEP) of Ⅰ were 0.887 and 0.444, respectively. Class Ⅱs Rp and RMSEP were 0.896 and 0.435, respectively. The results show that the prediction of class Ⅱ mushroom firmness is more accurate than classⅠ. Under the same conditions, the more feasible storage measures can be implemented for class Ⅱ mushroom, so we shall try to capture the pileus diameter of 3-5 cm of agaricus bisporus for production, processing and daily sales.