Impact of Contamination on the Characteristics and Foamability of Yeast Macromolecules Released during the Alcoholic Fermentation of a Model Grape Juice.

is a fungal pathogen responsible for the decrease in foamability of sparkling wines. The proteolysis of must proteins originating from botrytized grapes is well known, but far less information is available concerning the effect of grape juice contamination by . The impact from on the biochemical and physico-chemical characteristics of proteins released from during alcoholic fermentation remains elusive.

Influence of Grape Berry Maturity on Juice and Base Wine Composition and Foaming Properties of Sparkling Wines from the Champagne Region.

In sparkling wine cool-climate regions like Champagne, it is sometimes necessary to pick the healthy grape clusters that have a relatively low maturity level to avoid the deleterious effects of . In such conditions, we know that classical oenological parameters (sugars, pH, total acidity) may change but there is little information concerning the impact of grape berry maturity on wine proteins and foaming properties. Therefore, healthy grapes (Chardonnay and Pinot meunier) in 2015 and 2016 were picked at different maturity levels within the range of common industrial maturity for potential alcohol content 8⁻11% v/v in the Champagne region.

Effect of grape juice press fractioning on polysaccharide and oligosaccharide compositions of Pinot meunier and Chardonnay Champagne base wines.

Press fractioning is an important step in the production of sparkling base wines to segregate the grape juices with different qualities. Grape juice fractions were collected during the pressing cycle at industrial and laboratory scales. The Pinot meunier and Chardonnay Champagne base wines obtained from the free-run juice and the squeezed juices exhibited strong differences from the beginning to the last step of pressing cycle for numerous enological parameters.