Detectable Odor Thresholds of Selected Lipid Oxidation Compounds in a Meat Model System

Abstract

Organic compounds, pentanal, hexanal, t-Z-hexenal, t-2-heptanal, t-2-octenal, and t,t-2,4-decadienal, were added individually to lean ground beef. Detectable odor threshold (DOT) was determined by a lo-member sensory panel using triangle tests. Descriptive analysis using category scales measuring intensity was used to assess odor intensities contributed by specific compounds in an effort to relate quantitative differences in qualitative characteristics to oxidized beef. DOT for pentanal was 2.67 ppm; hexanal was 5.87 ppm; heptanal was 0.23 ppm; t-2-hexenal was 7.87 ppm; t-2-octenal was 4.20 ppm; and t,t-2,4-decadienal was 0.47 ppm. Common terms used to describe odor of meat containing added compounds were rancid, painty, and herbal.

Preliminary study of the volatile fraction in the raw meat of pork, duck and goose

“…For abbreviation and notes see Table 1. Vega, 1995). The short-chain acids have a sharp cheesy odour with the fatty odour, as for aldehydes, increasing with chain length (Rowe, 1997).…”

Use of dietary rosemary diterpenes to inhibit rancid volatiles in lamb meat packed under protective atmosphere

“…In quantitative terms, the aldehyde group, led by hexanal, is considered the main contributor to rancid odour in raw meat (Ross and Smith, 2006). The detectable odour threshold of hexanal in meat is relatively high (5.9 mg/kg) compared with those for other aldehydes, such as pentanal (2.7), 2-hexenal (7.9), heptanal (0.2), 2-octenal (4.2) or 2,4-decadienal (0.5), which are associated with rancid, painty and herbal odours (Brewer and Vega, 1995). Rancidity inhibition through a rosemarybased diet has been reported by Nieto (2009) in lamb meat.…”

Complex phenolic compounds reduce lipid oxidation in extruded oat cereals

“…Brewer and Vega (1995) included painty as a sensory descriptor to indicate production of the lipid degradation products hexanal, heptanal, 2-hexenal, 2-octenal and (E,E)-2,4-decadienal. These compounds were detected in extruded oat flours, particularly samples that had lipase activity and free fatty acids prior to extrusion, and those samples were characterized by a descriptive panel as ''stale oil'' and ''wet washing'' (Parker, Hassell, Mottram, & Guy, 2000).…”