Influence of chilling and thawing procedures on the origin of constituents of fluid lost from chicken carcasses

Synopsis

The present study has shown that more fluid, solids and crude protein were lost from thawing carcasses that had been mechanically chilled in iced water before freezing than from similar carcasses that had not been chilled. Even for carcasses that had not been chilled approximately 1 per cent of the carcass weight was lost as fluid and 0–15 per cent as solids during thawing and holding at 1° C. for 10 days. However, losses were negligible during rapid thawing at 30° C. for 4 hr. It appears that water taken up during chilling causes losses of crude protein and other solids, mainly from the skin, during thawing at 30° C. for 4 hr, but holding at 1° C. for 10 days causes losses both from the skin and from extracellular fluid.

Analyses of pectoralis major and gastrocnemius muscles have shown that there are no appreciable losses of solids or nitrogen from skeletal muscles during mechanical chilling and a trained taste panel could not detect any loss of flavour resulting from this procedure. Although gastrocnemius muscles from carcasses that had been mechanically chilled before freezing had slightly lower solids contents after thawing than the corresponding muscles from fresh, unchilled carcasses, there seem to be no important losses from skeletal muscles during thawing.

Notes

National Association of Poultry Packers (attached worker). Present address: H. J. Heinz Co. Ltd, Hayes Park, Middlesex.

Present address: Unilever Research Laboratory, Colworth House, Sharnbrook, Bedford.