The effect of castration on the headspace aroma components of cooked lamb

Minced lamb samples (lean meat or adipose tissue) from 12‐week‐old ram lambs and wethers were fried in the absence of added fat. The headspace aroma components were isolated onto Tenax GC prior to thermal desorption. A total of 132 compounds were identified and a further 31 were partially characterised by GC‐MS, 49 of which are reported here for the first time as components of sheep meat aroma. One of these, 4,6‐dimethyl‐1,3‐oxathiane, which has not previously been reported in any meat, was associated with a ‘stale/wet animal’ odour. All aroma isolates were dominated by products of lipid degradation with aliphatic aldehydes present in the highest relative amounts. Certain branched‐chain fatty acids have been implicated in the characteristic aroma of sheep meat, and 4‐methyloctanoic and 4‐methylnonanoic acids were identified at higher levels in the adipose tissue from entires than from wethers.