Relationships amongst South African processed, young and matured Cheddar cheese pertaining to organic acid content and non-starter population

Abstract

Ion-exclusion HPLC and selective media were used to analyse the organic acids and microbial population in processed, young and matured Cheddar cheeses. Microbial counts for young and matured Cheddar were much alike, with the exception of total acid formers and citrate fermenters which were higher for matured Cheddar. The total mesophilic count for processed Cheddar cheese was considerably higher than for conventional (young and matured) Cheddar cheeses, whereas the fungi count for processed Cheddar was lower. Total acid formers, lactobacilli, homofermentatives, citrate fermenters and aerobic spore-forming bacteria were all present in lower quantities in processed Cheddar than in the conventional Cheddars. Anaerobic spore-forming bacteria were detected only in the processed Cheddar cheese. Although HPLC chromatograms appeared relatively similar amongst the cheeses, a greater number of organic acids could be detected in matured Cheddar cheese than in young and processed Cheddar, respectively. The matured Cheddar cheese was clearly more developed with regard to propionic, butyric, citric, lactic, acetic, isovaleric and n-valeric acids. From radar plots it was deduced that microbial and organic acid profiles could be utilised as evaluation parameters for cheese varieties. ©