Linda F. Bisson Wine Flavor 101B March 23, 2012 Student pH Trial Linda F. Bisson Wine Flavor 101B March 23, 2012

Impacts of pH Changes Microbial survival and growth Microbial activity Color Color stability Polymerization reactions SO2/oxidation reactions

Experiment 80% Tempranillo/20% Syrah Juice pH: 3.7 Used sulfuric acid to drop pH to 3.3 and 3.5 Used sodium hydroxide to raise pH to 3.9

Results No inoculation 25 Brix 25 gallon fermentations run at 28°C No difference in fermentation rates Fermentations dry at 15 days, had a 5 day lag Aroma differences: only significant comparing pH 3.3 to pH 3.9

pH Tasting Glass 1: pH 3.3 juice/3.65 wine