Influence of somatic cell counts and breed on physico-chemical and sensory characteristics of hard ewes'-milk cheeses

The aim of the present work was to perform a physico-chemical, descriptive quantitative and consumer-preference analysis of hard ewes'-milk cheeses that had been matured for one year and to determine the correlations between the variables studied. The cheeses were elaborated with milk from three breeds of sheep (Castellana, Churra and Assaf) with different somatic cell counts (lower than 500000 cells ml(-1); between 1 000000 and 1 500000 cells ml-1, and more than 2 500000 cells ml(-1)). The results show that the cheeses elaborated with milk with high SCC had lower values of dry extract and fat and high values of pH and fat acidity and were described as pungent, granulose and less creamy. Regarding the effect of breed, the cheeses made with milk from the Churra breed had lower values for fat and those made with Assaf breed milk were significantly more rancid. The study of correlations showed that creaminess was positively correlated with the dry extract and total fat content and negatively correlated with ash and fat acidity, indeed grainy texture and pungency had the opposite sign in their correlation with these latter variables. The yellow colour was positively correlated with ash and negatively with protein. Finally, the consumer preferences reveals that the less accepted cheeses showed the higher values for rancidness and pungency and they were less likely to accept the cheeses made with Assaf breed milk.