Dong Wang
China Agricultural University, China
Title: Study on the generation mechanism and change regularity of characteristic
Biography
Biography: Dong Wang
Abstract
Raisins are a welcome dry fruit all around the world. They are either consumed directly or are used in cooking especially in desserts. The aroma of raisins affects consumers’ preferences. The aroma of raisin is determined by grape variety, drying method and storage environment. Over 100 volatile compounds were identified in different raisins by using gas chromatography-mass spectrometry (GC-MS) coupled with headspace solid-phase micro-extractions (SPME), the majority of raisin volatiles are derived from three sources: fresh grapes, the oxidative degradation of unsaturated fatty acids and the Millard reaction process. Most of the volatiles were existed in fresh grapes, while the furans (5-methyl furfural, 2-acetyl furan 2-pentyl furan) and pyrazines (2-ethyl-6-methyl pyrazine, 2, 6-diethyl pyrazine and 5-ethyl-2,3-dimethyl pyrazin) generated by Maillard reaction during grape drying, they contribute to characteristic “raisin” flavor, and determine the aroma characteristics of raisins. This program will study the evolutionary pattern of these volatiles responsible for the characteristic “raisin” flavor and their precusors (amino acids and monosaccharides) during grape drying by integrating GC-MS, HP-LC, model reaction and metabonomics technology. Then illustrate the generation source and reaction mechanism of the characteristic volatiles and dissect the influence of drying methods, storage packaging form and environment conditions on these volatiles. The results will provide strong academic supports and practical technology for manipulation of the flavor of raisins.