PROTEOLYTIC CHANGES DURING PROCESSING IN TURKISH DRY‐CURED MEAT PRODUCT (PASTIRMA) WITH DIFFERENT SALT LEVELS

Abstract

ABSTRACTThe effects of different salt (NaCl) contents on proteolytic changes during processing in the dry‐cured meat product pastırma were investigated. Pastırma samples were produced with three different NaCl levels (3, 6 and 9%) and proteolytic changes were monitored.A progressive increase in nonprotein nitrogen (NPN) and free amino acids (FAAs) was detected during processing. High‐salt pastırma samples had the highest FAAs. Drying and pressing stages before pasting with çemen resulted in a decrease in water‐soluble nitrogen (WSN) and a slight increase in NPN and FAA. High salt level and processing time resulted in the accumulation of FAAs. The increase in WSN, NPN and FAA contents after çemen treatment indicated that the çemen used in the pasting process had an impact on accumulation of these components in pastırma. However, no significant effect of salt level was observed on WSN and NPN. Sarcoplasmic proteins decreased considerably after salting due to drainage. Myofibrillar proteins degraded during processing, particularly in samples with 6 and 9% NaCl.PRACTICAL APPLICATIONSProteolysis is one of the most important biochemical changes occurring during the processing of dry‐cured meat products such as ham or pastırma. The effect of additional salt concentrations and processing stages on proteolysis in Turkish dry‐cured meat product, pastırma, was studied during processing. Processing stages (salting, drying, pressing and pasting with çemen mixture) resulted in increases in NPN and FAA contents. High salt level (9% NaCl) and processing stages, particularly pasting with çemen mixture, facilitated the accumulation of FAA. Salting resulted in denaturation or insolubilization of proteins. Insolubilization of sarcoplasmic proteins was clearly seen in samples with 6 and 9% NaCl, depending on increased salt concentration during processing. In contrast, myofibrillar proteins in samples with 6 and 9% NaCl degraded during processing. From these results, processing conditions (salt concentration of pastırma and pasting with çemen) can determine the compounds released from protein breakdown during processing.