In order to search for a new method for the quick detection of walnut oil quality,the adulterated walnut oil samples were tested by low field-nuclear magnetic resonance(LF-NMR),and the relaxation data of CPMG sequence were analyzed and processed by chemometric methods including principal component analysis(PCA) and partial least squares regression(PLSR).The adulterated walnut oil samples with soybean oil,corn oil or sunflower oil and pure walnut oil were used for the LF-NMR detection and evaluation.The experimental results showed that PCA can distinguish pure walnut oil and different kinds of adulterated walnut oil.Moreover,the adulterated walnut oil samples display regular distribution with different adulterated ratios.The CPMG data and actual adulteration value were adopted for the quantitative analysis of walnut oil adulteration level by PLSR.Therefore,the combination of LF-NMR technology and chemometrics could provide a fast,non-destruction and accurate method for the detection of walnut oil adulteration,and show a great application potential in control and evaluation of edible oil products quality.
关键词
化学计量学主成分分析(PCA)偏最小二乘回归(PLSR)低场核磁共振(LF-NMR)掺假核桃油
Keywords
chemometricsprincipal component analysis(PCA)partial least squares regression(PLSR)low field-nuclear magnetic resonance(LF-NMR)adulterated walnut oil