title: Effect of different lysis treatments on the characteristics of yeast derivatives for winemaking.
abstract: The effects of three preparation techniques on the oenological properties of a yeast autolysate were investigated: enzymatic autolysis, thermolysis, and the combination of a slow freezing-defrosting and mechanical disruption were carried out on a commercial formulation of active dry yeasts (Saccharomyces cerevisiae). The powders obtained by freeze drying, were characterized: volatile compounds were analyzed by SPME-GC with mass spectrometric (MS) and olfactometric detection (O); the release of colloids in winelike solution was studied by SDS-PAGE and size exclusion chromatography (SEC). Finally, the effects of the powders addition on the aroma composition of a white wine were investigated by SPME-GC-MS, SPME-GC-O, and sensory evaluation. The products obtained were quite different from each other. In particular, enzymatic autolysis led to higher contents of nonglycosilated soluble proteins in the powders and determined a higher retention of wine aroma compounds. On the contrary, thermal autolysate was richer in glycoproteins, and it was able to increase the wine aroma intensity; nevertheless, in the wines treated with such preparation, a slight yeastlike olfactory note was perceived.
authors.affiliation: Dipartimento di Scienze degli Alimenti via Sondrio, Università degli Studi di Udine, 2/A, 33100 Udine, Italy. piergiorgio.comuzzo@uniud.it
authors.forename: Piergiorgio
authors.initials: P
authors.lastname: Comuzzo
authors.forename: Lara
authors.initials: L
authors.lastname: Tat
authors.forename: Anna
authors.initials: A
authors.lastname: Liessi
authors.forename: Laura
authors.initials: L
authors.lastname: Brotto
authors.forename: Franco
authors.initials: F
authors.lastname: Battistutta
authors.forename: Roberto
authors.initials: R
authors.lastname: Zironi
mesh_terms: D000328:Adult; D003102:Colloids / Q000032:analysis; D005260:Female; D005511:Food Handling / Q000379:methods*; D005612:Freeze Drying; D005615:Freezing; D006023:Glycoproteins / Q000032:analysis; D006026:Glycoside Hydrolases / Q000378:metabolism; D006358:Hot Temperature; D006801:Humans; D008297:Male; D008875:Middle Aged; D009812:Odorants / Q000032:analysis; D011208:Powders; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D012903:Smell; D014920:Wine / Q000032:analysis / Q000382:microbiology*
chemical_list: D003102:Colloids; D006023:Glycoproteins; D011208:Powders; D006026:Glycoside Hydrolases