SUMMARY: The 35 parts per billion (ppb) H2S in freshly prepared broth and the 180 to 730 ppb H2S in meat of freshly simmered, roasted and fried chicken all substantially exceed the 10 ppb H2S odor threshold in water. Hence, HeS contributes directly to the aroma of these products. Freezing, thawing and reheating can reduce the H2S in broth to subthreshold levels thus indicating the transient nature of its direct contribution to aroma. In a model system, H2S was passed through molten chicken fat containing 5% acetaldehyde. After expulsion of excess H2S and acetaldehyde the residual highly odorous fat exhibited a fixed sulfur content. These exploratory results, together with related results reported in the literature, suggest that a reaction beween HIS and acetaldehyde was involved and that such interactions between H2S and carbonyls in fat could be quite general. Thus H2S mav also contribute to cooked chicken flavor and aroma through the formation of such secondary products. Copyright © 1969, Wiley Blackwell. All rights reserved