The effect of a commercial starter culture addition on the ripening of an artisanal goat's cheese (Cameros cheese)

Abstract

D P. TO R RE . 2000. The evolution of physicochemical parameters, and the most important microbial groups, were determined for the following three batches of 'Cameros' goat's milk cheese during ripening: Batch R elaborated with raw milk, Batch RS elaborated with raw milk and with the addition of a starter culture, and Batch PS elaborated with pasteurized milk and with the addition of the same culture. No differences in total solids (TS) or in the content of NaCl, fat and total nitrogen (expressed as percentages of TS) were found during the ripening. The pH, fat acidity and non-protein nitrogen (NPN, expressed as a percentage of TN) showed significant differences between the batches. The inoculated batches showed the fastest drop in pH at the beginning of the ripening period, but the cheeses of Batch R showed a higher degree of lipolysis and proteolysis. The addition of a starter influenced the microbiological quality of the cheeses. Differences in the counts of Enterobacteriaceae and faecal coliforms were found between Batches R and RS after 15 days. Staphylococcus aureus increased in number during the early period of ripening and attained a population above 6 log cfu g −1 in Batch R in the period from 5 to 10 days. However, enterotoxins were not detected in this Batch. Batch R showed lower values of lactic acid bacteria at the beginning of the ripening period, but no significant differences were found between batches in the period from 5 to 15 days of ripening. At the beginning of the ripening, Lactococcus was the main lactic acid bacteria, with L. lactis lactis being predominant. After 15 days, the lactic acid bacteria counts decreased in the three batches, especially in the cheeses of Batch PS (only 2·2 log cfu g −1 was found at 60 days), as lactococci (the only lactic acid bacteria present in Batch PS) are incapable of growing under the conditions found in cheeses at the end of their ripening period. At this time, Lactobacillus was the predominant genus in Batches R and RS, with L. plantarum predominant. No lactococci were found from day 30 in Batch R and from day 40 in Batch RS. The cheeses of Batch RS received the most favourable scores from the tasting panel for all attributes judged: cut appearance, colour, aroma, taste, texture and general acceptance.

Polyphasic Approach to Bacterial Dynamics during the Ripening of Spanish Farmhouse Cheese, Using Culture-Dependent and -Independent Methods

“…Low levels of enterococci were isolated during the initial ripening period but not thereafter. The presence of this bacterial group in cheese seems to vary depending upon the type of cheese, and this presence has been associated with the use of raw milk (11,33,38) and also the season when the cheese is made. As far as non-LAB populations are concerned, no Enterobacteriaceae were detected and 10 4 CFU/g of staphylococci were found in the final product.…”

“…Although these organisms are usually present at low levels in curd (10 2 to 10 3 CFU/g), their concentrations increase during ripening to 10 7 to 10 8 CFU/g (15,21). NSLAB have been reported to be responsible for many of the flavor qualities of cheese, and their use as adjuncts to starter cultures might either improve taste or introduce off-flavors, depending upon the strains used (4,38,43).…”

Staphylococcus aureus: Characterisation and Quantitative Growth Description in Milk and Artisanal Raw Milk Cheese Production

“…Olarte et al [82] observed differences in S. aureus growth in dependence on the addition of starter culture. In cheese without added starter culture, S. aureus exceeded concentrations higher than 5 log counts in 5 days.…”

Physicochemical, textural, volatile, and sensory profiles of traditional Sepet cheese

“…Zeytineli cheese produced with natural rennet had a higher lactic acid bacteria population than did Germiyan cheese that was produced with commercial rennet (data not shown). Olarte et al (2000) reported the relation of lactic acid bacteria and initial lactic acid formation. Hatzikamari et al (1999) also observed higher initial levels of lactic acid bacteria in low-pH cheeses.…”