Sensory Examination of Four Organic Acids Added to Wine



Difference thresholds for 4 organic acids, determined at a reference concentration of 0.615 (as g of tartaric acid per 100 ml), were found to be ±0.13 g per 100 ml for tartaric, ±0.18 g per 100 ml for citric, ±0.10 g per 100 ml for fumaric, and ±0.13 g per 100 ml for adipic. The response reaction of the panel to these acids appeared to be to molar concentration rather than to pH or normality when dealing with near-threshold amounts added to a highly buffered medium.

When the acids were compared directly by addition of equal molar amounts of each, to a wine (equal to 0.20 g tartaric acid per 100 ml on a molar basis), citric acid was judged most sour, fumaric and tartaric about equal, and adipic the least sour. Preference, data indicated trends in favor of citric and tartaric acids over fumaric and adipic acids.