Diacetyl was detected at about 0.2 ppm using a two alternative forced
choice procedure. Consumer acceptance for cottage cheese showed a smal
l effect of added diacetyl, peaking at 1.0 ppm for aroma acceptance an
d flavor acceptance. Patterns of acceptance across diacetyl levels wer
e similar for both frequent and infrequent consumers. Consumer accepta
nce tests conducted in a campus-based sensory testing facility gave si
milar results to tests conducted in a shopping mall, although the mall
data were more variable.