The Effect of Air Velocity on Weight-Loss of Botrytised Grapes in Natural Sweet Wine Production

Abstract

Four lots of botrytis-infecfed Semillon grapes were held at 20°C (68°F) and 60 percent relative humidity and exposed to air velocities of 0-10, 5-30, 15-55, and 50-75 fpm, respectively. On the fourteenth day following infection the respective lots had lost 48, 52, 59, and 66 percent of their original weight, and yielded musts of 35°, 37°, 43°, and 51° Balling. These lots reached 35° Balling on the fourteenth, thirteenth, eleventh and tenth days, respectively.

The amount of undesirable microbiological activity was inversely related to the rate of air movement. Peniccilium spp. and Aspergillus niger were the principal spoilage organisms.