Integrative metabolomics-flavoromics to monitor dynamic changes of ‘Nam Dok Mai’ mango (Mangifera indica Linn) wine during fermentation and storage

Abstract

The ‘Nam Dok Mai’ variety is an important mango variety with a short shelf-life. Wine production is one of the new opportunities to process such low-quality mangoes. ‘Nam Dok Mai’ mango juice with 22 °Brix and pH 4 was prepared. Laboratory scale fermentation was done at 20 ± 2 °C for 18 d. After fermentation was completed, the mango wine was bottled and stored at 10 to 12 °C for 3 months. The pH of the mango wine decreased from 0 to 4 d and then remained stable at ~pH 3 to the end of fermentation. The Brix sucrose of the product decreased from 22 to 3.6 °Brix at 12 d of fermentation and was stable thereafter. The alcohol percentage of the samples increased to 13% by the last fermentation day and then dropped to 11% during storage. Fifty-six compounds could be identified using metabolomic analysis accounting for ~40% of all metabolites during fermentation and storage. Principal component analysis was used to differentiate all samples based on the metabolites and flavor compounds observed. The finished mango wine was separated from other samples along a PC biplot by acid compounds. Relative targeted quantification using heat plots of the metabolite and flavor components showed decreases in fatty acid methyl esters (FAME), free fatty acids, fatty alcohols, sugars, and terpenes during fermentation. On the other hand, acids, glycerol, ethyl esters, and higher alcohols increased during fermentation. Correlation analysis resulted in a strong positive relationship between FAME with sterols, sugars, higher alcohols, ketones, aldehydes, terpenes, and volatile acids.