# Preliminary Investigation of Fruit Mash Inoculation with Pure Yeast Cultures: A Case of Volatile Profile of Industrial-Scale Plum Distillates

## TL;DR

This study compares pure yeast fermentation and spontaneous fermentation in plum brandy production, focusing on how each affects the final product's volatile compound profile.

## Contribution

The study provides new insights into how pure yeast cultures influence volatile compound concentrations in industrial-scale plum distillates.

## Key findings

- Distillates with pure yeast cultures had higher ester concentrations than wild fermentation.
- Limiting raw material storage reduces 1-propanol production risk.
- Distillate heart removal beyond 450 g/L ethanol yields minimal volume increase but raises heating costs.

## Abstract

This study investigates the effect of pure yeast culture fermentation versus spontaneous fermentation on the volatile compound profile of industrially produced plum brandy. Using traditional distillation methods, the evolution of key volatile compounds is monitored at seven different moments during the distillation process. By integrating advanced analytical techniques such as GC-MS and sensory evaluation, significant differences in the composition of the distillates are highlighted, particularly in terms of ethyl esters and higher alcohols which are key to the sensory properties of the final product. Distillates produced with the addition of pure cultures gave higher concentrations of esters than those obtained by wild fermentation. The results of our industrial research show that the most critical step is to limit the storage of the input raw material, thereby reducing the subsequent risk of producing higher concentrations of 1-propanol. Furthermore, our results indicate that the heart of the distillate can only be removed up to an ethanol content of approximately 450 g/L and that the removal of additional ethanol results in only a 10% increase in the total volume of the distillate, which in turn results in an increase in boiler heating costs of approximately 30%.