Diversity Analysis of Volatile Flavor Compounds of Corn with Various Storage Years Based on SPME-GC-MS/MS and Multivariate Statistical Analysis

Abstract

Flavor compounds are important indicators of edible quality and nutritional value of corn. The quality deterioration of corn during storage is closely related to its flavor compounds. Corn samples harvested in four years from 2019 to 2022 were detected by solid phase microextraction-gas chromatography-triple quadrupole mass spectrometry (SPME-GC-MS/MS), and multivariate statistical analysis of flavor compounds relative content was carried out by principal component analysis and partial least squares discriminant analysis. The results showed that 129 volatile flavor compounds were detected in corn, including alcohols, aldehydes, ketones, esters, benzenes, heterocycles, acids, ethers, hydrocarbons and phenols. The multivariate statistical analysis showed that volatile flavor compounds and storage years of corn were correlated. According to the importance of variable projection, 47 compounds had significant diversity between corn samples with various storage years. Among them, the relative contents of 1-octen-3-ol, neryl butyrate and 2-pentylfuran increased with the extension of corn storage years, while the relative content of pantolactone, methyl octanoate and 2-acetylfuran decreased with the extension of corn storage years. These 6 compounds were identified as characteristic differential compounds. The partial least squares discriminant analysis classification model was constructed, and had good discrimination for corn storage years (R2=0.99, Q2=0.97, prediction accuracy was 1). The model will provide technical means for dynamic monitoring of corn storage quality, which is of great significance for ensurance national food security and reduce grain loss.

Keywords

• corn
• storage years
• flavor compounds
• multivariate statistical analysis
• spme-gc-ms/ms