Impact of oxygen supplementation during fermentation on yeast gene expression and thiol release in wine.

Traditionally, oxygen supplementation has been more strongly associated with yeast vitality and sugar consumption kinetics than with aroma metabolism. This study investigated the effects of oxygen exposure during the exponential growth phase of yeast cells on the polyfunctional thiol profile of wine. Using quantitative real-time RT-PCR, the expression of five genes related to amino acid and peptide uptake, as well as two genes associated with β-lyase activity, was analyzed.

Influence of flash heating and aspergillopepsin I supplementation on must and wine attributes of aromatic varieties.

The protein instability with haze formation represents one of the main faults occurring in white and rosé wines. Among the various solutions industrially proposed, aspergillopepsin I (AP-I) supplementation coupled with must heating (60-75 °C) has been recently approved by OIV and the European Commission for ensuring protein stability of wines. This study investigates the impact of AP-I either applied independently or in combination with flash pasteurization on the chemical composition of grape must and wines derived from Sauvignon Blanc and Gewürztraminer.

Impact of on Chemical Composition and Sensory Profiles of Viognier Wines.

Viognier is a warm climate grape variety prone to loss of acidity and accumulation of excessive sugars. The yeast can improve the stability and balance of such wines due to the partial conversion of sugars to lactic acid during alcoholic fermentation. This study compared the performance of five strains in co-inoculations and sequential inoculations with in high sugar/pH Viognier fermentations.

Impact of Lachancea thermotolerans on chemical composition and sensory profiles of Merlot wines.

Wines from warm(ing) climates often contain excessive ethanol but lack acidity. The yeast Lachancea thermotolerans can ameliorate such wines due to partial conversion of sugars to lactic acid during alcoholic fermentation. This study compared the performance of five L.