Origin and Nature of Aroma in Fat of Cooked Poultry

Abstract

SUMMARY: Fat of raw poultry, separated from solid tissue and washed with water at temperatures not exceeding 40°C does not contain cooked poultry aroma and does not develop it when heated. Hence, cooked poultry aroma cannot be derived from the fat alone. Washed and filtered fat from cooked poultry contains characteristic cooked poultry aroma dissolved in it. The aroma of this fat is caused by compounds which dissolve in it during cooking and which apparently stem from nonfat or lean portions of the meat. The ability of fat to dissolve or acquire substances during cooking was demonstrated by showing that fat of cooked poultry contains more sulfur than does fat of raw poultry. Less than 2% of this sulfur build‐up occurs as hydrogen sulfide. The magnitude of the sulfur build‐up was 8 to 14 times greater in the fat of roasted poultry than it was in the fat of simmered chicken. Authentic amino acids in contact with poultry fat at a typical roasting temperature readily underwent Strecker type degradation. Furthermore, aroma components representing typical amino acid degradation products were found in fat from roasted turkey. These analytical results indicate protein, amino acids and probably also sugars and other water soluble components are invoved in aroma formation. Hence fat contributes to cooked poultry aroma indirectly and passively through its ability to dissolve and retain aroma components formed during cooking. Consequently, the characteristic cooked poultry aroma in fat of cooked poultry is not derived from the fat itself but comes from and is thus dependent on the “lean”.

Effect of some water-soluble components on aroma of heated adipose tissue

“…Species-specific compounds are formed on heating lipids. The studies described here and the work of Pippen et al (1969) with raw chicken lipids, however, suggest this does not occur. Pork was identified from its heated lipids, but the aroma produced was not characteristic of pork food products; it was a "piggy" odor, possibly from thermal degradation of unsaturated fatty acids in the lipid.…”

“…Aroma components, developed by thermal degradation of or reactions occurring in lean meat, may be dissolved in the lipid fraction. Pippen et al (1969) claim this is the role of fat in chicken aroma. Other preformed fat-soluble components may be liberated as heat increases their vapor pressure.…”

“…Interaction between compounds produced on heating both lipid and lean meat. Pippen and Mecchi (1969) suggested H,S produced from amino acids or proteins reacted with carbonyls from thermal degradation of fatty acids to form odors that contribute to chicken aroma. Interaction directly between lean and lipids.…”

Protein hydrolysis—the key to meat flavoring systems

“…This is exemplified by the basic findings of earlier workers on the nature of meat flavor and its precursors. The latter were successfully extracted with ice-cold water from fresh meat, first by Hornstein and Crowe (58, 59), Batzer et al (60), Wasserman and Gray (61), and Pippen et al (62), and later by many others. It was concluded that the precursors are water soluble and of relatively low molecular weight.…”

Effect of Charcoal Broiling on the Formation of Volatile Compounds in Gamma-Irradiated Dakgalbi, a Korean Chicken-Based Food

“…Although the mechanism of forcming alkyl-benzenes is not clear, Watanabe and Sato (1971) has shown that various alkyl-benzenes was formed in swallow fried beef, and toluene, xylene and benzene derivatives have been reported to be formed from carotenoids (Borenstein and Bunnell, 1966;Pippen et al, 1969). Jo and Ahn (2000) have also suggested that bovine serum albumin, gelatin and myofibril proteins might be precursors of the benzene derivatives.…”