Freeze‐dried turkey muscle I.—Changes in nitrogenous compounds and lipids of dehydrated turkey during storage

Changes in proteins and lipids were followed during the storage of freeze‐dried turkey breast muscle in air and in nitrogen. Oxidation of sulphydryl groups accounted for part of the oxygen uptake of air‐stored samples, and was accompanied by a decrease in soluble nitrogen greater than in controls stored in nitrogen. The major deteriorative process at low moisture content was a type of ‘lipid’ browning reaction which was dependent on oxygen and caused discoloration and objectionable odours. Autoxidation of lipids catalysed by haem pigments and resulting in rancid flavours was not a major deteriorative process in freeze‐dried turkey muscle. Lipid hydrolysis occurred at water contents of 8·2 and 5·4% but not at 0·8%.