DRY-CARED HAM FLAVOR - ENZYMATIC GENERATION AND PROCESS INFLUENCE

The processing of dry-cured ham is very complex and involves numerous biochemical reactions that are reviewed in this paper. Muscle proteins undergo an intense proteolysis resulting in a great number of small p eptides and high amounts of free amino acids. The enzymes responsible of these changes are proteinases (cathepsins B, D, H and L and, to a l ess extent, calpains) and exopeptidases (peptidases and aminopeptidase s). Muscle and adipose tissue lipids are also subject to intense lipol ysis generating free fatty acids by the action of lipases that, in a s econd stage, are transformed to volatiles as a result of oxidation. Se nsory profiles of dry-cured ham are strongly affected by these enzymat ic reactions. In addition, the activity levels of the muscle enzymes s ignificantly depend on the properties of raw ham, such as age and cros sbreeding as well as the process conditions such as temperature, time, water activity, redox potential and salt content. Thus, the control o f the muscle enzyme systems, mainly proteases and lipases, is essentia l for the optimal standardisation of the processing and/or enhancement of flavour quality of dry-cured ham. (C) 1997 Elsevier Science Ltd.