# Effect on Arabica Coffee Flavor Quality of Enhanced Fermentation With Pichia membranifaciens Through Change Microbial Communities and Chemical Compounds

## TL;DR

This study shows how adding Pichia membranifaciens during coffee fermentation changes microbes and chemicals to improve Arabica coffee flavor.

## Contribution

The study identifies specific microbial and chemical changes caused by Pichia membranifaciens in coffee fermentation.

## Key findings

- Enhanced fermentation with Pichia membranifaciens altered microbial communities in coffee.
- 122 nonvolatile and 26 volatile compounds changed significantly during fermentation.
- Pichia membranifaciens inhibited other microbes and stabilized coffee flavor quality.

## Abstract

To stabilize Arabica coffee quality by enhanced fermentation with Pichia membranifaciens, high‐throughput sequencing, UPLC–MS/MS, HS‐SPME‐GC–MS, and SCA cupping protocol were employed for comprehensive analysis of the coffee fermentation process. Gene sequencing showed that the predominant microorganisms at the genus level were Weissella, Lactococcus, Trichococcus, Leuconostoc, and Massila for bacteria and Pichia, Hanseniaspora, Lachancea, Candida, and Cystofilobasidium for fungi. Meanwhile, 122 and 122 differentially changed nonvolatile compounds (VIP > 1, p < 0.05, FC > 1.5 or FC < 0.65) from 2275 nonvolatile compounds were found between PE2 versus PB2 and PE3 versus PB3, respectively. Furthermore, 26 differentially changed volatile compounds (VIP > 1, p < 0.05, FC > 2.0 or FC < 0.50) were found between PE and PB. Therefore, enhanced fermentation with P. membranifaciens inhibited the growth of other microorganisms and changed the chemical compounds during the fermentation to stabilize flavor quality.

Weissella, Lactococcus, Trichococcus, Leuconostoc, and Massila at the bacterial general level and Pichia, Hanseniaspora, Lachancea, Candida, and Cystofilobasidium at the fungi general level were the predominant microorganisms during the enhanced fermentation of Arabica coffee. Meanwhile, 122 differentially changed nonvolatile compounds (VIP > 1, p < 0.05, FC > 1.5 or FC < 0.65) were found between PE and PB. Furthermore, 26 differentially changed volatile compounds (VIP > 1, p < 0.05, FC > 2.0 or FC < 0.50) were found between PE and PB.