Physico‐chemical, biochemical and microbiological changes of Kumpia wieprzowa during ripening

Purpose – The purpose of this paper is to estimate physico‐chemical, biochemical and microbiological changes during the three‐month ripening of the Polish traditional raw smoked fermented meat product Kumpia wieprzowa, produced from pork shoulder without fore‐shank.Design/methodology/approach – After one, two and three months, the pH, aw, chemical composition, the content of nitrogen – total and soluble – as well as the profile of aromatic compounds and microflora, were evaluated.Findings – During ripening, the water content decreased from 62.7 percent to 47.5 percent, while the protein and fat amount increased from 20.8 percent to 25.0 percent and from 9.7 percent to 16.3 percent, respectively; the aw decreased from 0.95 to 0.88 and pH from 5.80 to 5.35. The proteolytic changes, measured by free amine groups and Nsoluble content, as well as the quantity of free fatty acids and percentage of most of the volatile compounds increased, particularly during the first two months of ripening. The total number of aerobic microorganisms, and Lactobacillaceae decreased during ripening from 7.9 to 6.2 and 5.6 to 4.7 log cfu/g, respectively. The count of coagulase‐negative cocci changed from 5.3 to 5.2 log cfu/g.Originality/value – Kumpia wieprzowa is a unique pork product, entered on the List of Polish Traditional Products in 2005. Up to the present, the properties of Kumpia wieprzowa were not recognized and published in the scientific literature, in spite of its very interesting raw material (shoulder spontaneously fermented as a whole large primal cut).