Discrimination of Pineapples Varieties based on Volatile Organic Compounds using Chromatographic and Chemometrics Analysis

Abstract

This study analyzed the volatile organic compounds (VOCs) of four different pineapple varieties (MD2, Sarawak, Josephine and Morris). Head Space-Solid Phase Micro Extraction (HS-SPME) was used to extract the VOCs of those pineapples using Gas Chromatography-Mass Spectrometry (GC-MS). Analysis of pineapples extracts identified many types of VOCS including esters, alcohols, terpenes, aldehydes, ketones, saturated hydrocarbons and phenols. Thirtyfive selected VOCs were used for varietal discrimination using chemometrics techniques namely principal components analysis (PCA), cluster analysis (CA) and discriminant analysis (DA). The application of PCA and CA was able to group the pineapple samples according to their varieties based on their respective VOCs. Standard mode DA had discriminated the samples with 98.75% correctness using all 35 VOCs. The identification of significant compounds found in the studied samples was successfully confirmed (p<0.05) by PCA. The total variance of PC1 and PC2 is 63.34% exhibiting that the ester compounds show strong and moderate loading values. One of the unique identifiers is the presence of β-Myrcene with a loading value 0.93 found in PC1 where it is described as pleasant terpenes odor and balsamic descriptor. GCMS and chemometric techniques provided meaningful chemically quantitative data.