RT Journal Article SR Electronic T1 Review: Characterization and Role of Grape Solids during Alcoholic Fermentation under Enological Conditions JF American Journal of Enology and Viticulture JO Am J Enol Vitic FD American Society for Enology and Viticulture SP 133 OP 138 DO 10.5344/ajev.2015.15060 VO 67 IS 2 A1 Erick Casalta A1 Aude Vernhet A1 Jean-Marie Sablayrolles A1 Catherine Tesnière A1 Jean-Michel Salmon YR 2016 UL http://www.ajevonline.org/content/67/2/133.abstract AB During wine production, grape solids have a large impact on the fermentation characteristics and organoleptic qualities of the resulting wine. Here we review the research on grape solids. We begin by focusing on the origin, physical characteristics, and composition of these solids and on the changes in these factors that occur during fermentation. We then consider the impact of solids on fermentation, the role of sterols, the control of solids, and interactions between solids and other nutrients. Solids exert their effects on alcoholic fermentation mainly by modulating lipid supply. The balance between solids content and nitrogen is a key factor in fermentation control. The study of grape solids is in its infancy and requires further development. Knowledge of the composition of these solids and of sterol uptake mechanisms by yeast should facilitate improvements in fermentation control.