A study of chemical profiles and appearance of white crystals in Istrian dry-cured ham: effect of desalting

Abstract

In order to find out the effect on physical-chemical profile of Istrian dry-cured ham with particular regard to the appearance of white crystals in the muscles, raw salted legs were desalted by soaking the legs in cold water for 24 hours. The 20 raw hams taken from 10 slaughtered hogs (Swedish Landrace breed) and processed in the traditional Istrian manner were used. After salting and pressing, the raw hams were divided into two groups: 1) the 10 left legs of each hog were desalted (D); 2) the 10 right legs were not desalted (N). Following this, both groups of legs were subjected to continuous processing. Samples for chemical analysis and counting of white spots were taken from the 20 legs (10 N and 10 D) from 10 hogs, each weighing 12 to 15 kg. Chemical analysis of muscle tissue showed a highly significant difference (P<0.0001) in the salt quantity in the N (6.85%) and D (5.31%) dry-cured hams, as expected. Desalting affected the level of calcium which was higher (P=0.0124) in the D hams (0.27 g) than in the N hams (0.22 g). Desalting did not affect the free amino acid content, with the exception of methionine which was lower (P=0.0041) in D (0.14 g) than in N hams (0.17 g). Desalting affected the level of two free fatty acids as follows: heptadecanoic acid was higher (P=0.0203) in N (0.18%) than in D hams (0.24%) and DPA was higher (P=0.0373) in N (0.49%) than in D hams (0.39%). By counting the white precipitates, it was established that the regularity of appearance of the precipitate was noted on both the D and N hams, such that where there was no precipitate on the right N ham, nor was their any on the left D ham of the same hog. However, desalting only lead to a slight decrease in the appearance of precipitates (average of 0.7 points), but it is certain that desalting reduces the salt content in the legs, which affects some physical-chemical changes in the ham tissues during processing.