Evaluation of Yeast Diversity During Wine Fermentations with Direct Inoculation and pied de cuve Method at an Industrial Scale

Abstract

The diversity and composition of yeast populations may greatly impact wine quality. This study investigated the yeast microbiota in two different types of wine fermentations: direct inoculation of a commercial starter versus pied de cuve method at an industrial scale. The pied de cuve fermentation entailed growth of the commercial inoculum used in the direct inoculation fermentation for further inoculation of additional fermentations. Yeast isolates were collected from different stages of wine fermentation and identified to the species level using Wallersterin Laboratory nutrient (WLN) agar followed by analysis of the 26S rDNA D1/D2 domain. Genetic characteristics of the Saccharomyces cerevisiae strains were assessed by a rapid PCR-based method, relying on the amplification of interdelta sequences. A total of 412 yeast colonies were obtained from all fermentations and eight different WL morphotypes were observed. Non-Saccharomyces yeast mainly appeared in the grape must and at the early stages of wine fermentation. S. cerevisiae was the dominant yeast species using both fermentation techniques. Seven distinguishing interdelta sequence patterns were found among S. cerevisiae strains, and the inoculated commercial starter, AWRI 796, dominated all stages in both direct inoculation and pied de cuve fermentations. This study revealed that S. cerevisiae was the dominant species and an inoculated starter could dominate fermentations with the pied de cuve method under controlled conditions.

Use of fortified pied de cuve as an innovative method to start spontaneous alcoholic fermentation for red winemaking

“…, Li et al. ). This technique is based on the inoculation of a given amount of must, previously subjected to a partial AF, into a new must.…”

“…In this way, the amount of starter inoculum is reduced and, overall, it is possible to transfer desirable oenological features of yeast strains from a successful fermentation to a new must (Li et al. ). If the pied de cuve is a spontaneously fermented AF, the use of pied de cuve might limit but not exclude the risks, such as growth of spoilage microorganisms, stuck AF and formation of off‐flavours, related to the winemaking processes carried out without the inoculum of starter cultures.…”

An innovative method to produce green table olives based on “pied de cuve” technology

“…The technology of "pied de cuve" (PdC), largely used for wine production (Ubeda Iranzo et al, 2000;Clavijo et al, 2011;Li et al, 2012), limits the reduction of the microbial complexity of the driven processes. This method promote the growth of the desirable microbial strains in a small volume of grape must which act as a starter inoculums for higher volumes, but does not exclude the risk of development of unwanted microorganisms.…”

“…This method promote the growth of the desirable microbial strains in a small volume of grape must which act as a starter inoculums for higher volumes, but does not exclude the risk of development of unwanted microorganisms. Usually, the ratio PdC/bulk for wine application is 1/10 (Li et al, 2012).…”

Effect of the mechanical harvest of drupes on the quality characteristics of green fermented table olives

“…To our knowledge, no study has so far been carried out to evaluate the effects of the mechanical harvesting of drupes on the final characteristics of table olives. Limited information has been published on the rheological characteristics of drupes just after mechanical harvesting, but no data are available on the microbial and chemical features of the product during fermentation.…”