Pre-treatment of grape marc increases the biochemical conversion of cellulose in the presence of cellulases. Liberation of the monomer glucose in Sauvignon Blanc
marc (A) and Cabernet Sauvignon (B) was measured over 48 h. Grape samples were treated with 0.5 M sulfuric acid or water at elevated temperatures (1 h, 121 C). The rate of
saccharification of pre-treated grape marc is compared to non-pre-treated AIR grape marc and expressed as a percentage of cellulose converted into glucose.