A proposed methodology to determine the sensory evaluation of a fresh goat's cheese (Cameros cheese): Application to cheeses packaged under modified atmospheres

A sensory profile was proposed, together with a methodology which permited the quality control of a fresh goat's cheese (Cameros cheese) from the sensory standpoint. Samples of Cameros cheese from four different cheesemakers were evaluated by a jury of 10 members. All panelists attended five tasting sessions to define an agreed lexicon of sensory characteristics of Cameros cheese. In order to quantify each one of the sensory attributes, a scorecard was elaborated. The intensity of the attributes selected was quantified on a scale from 1 to 7 according to the indications given in the sensory description. For each attribute the optimum score was established by the panelists to obtain the numerical score of samples. Using the proposed system, the sensory quality of Cameros cheeses packaged under modified atmospheres was evaluated. Five different modified atmosphere conditions were studied (carbon dioxide/nitrogen mixtures and vacuum) and compared to control cheeses packaged in air. The product stored at 3-4°C was evaluated periodically. After 14 days of storage, the sensory characteristics of the control cheeses were unacceptable in all the parameters studied. However, the overall score for cheeses stored in 40 and 50% CO2 did not change substantially, retaining a reasonable acceptability until the end of the storage period. The 100% CO2 atmosphere had a very negative effect on the sensory quality specially in taste. Cheeses packaged under vacuum showed a fast deterioration of surface appearance and texture. The proposed methodology allowed the quantification of the sensory differences between the packaging conditions investigated. With regard to Cameros cheese, packaging in 50%CO2/50%N2 and 40%CO2/60%N2 were the most effective for retaining good sensory characteristics specially in taste and odour. However, texture and appearance were negatively affected by these conditions. © 2001 Elsevier Science Ltd

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

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

Microbiological and nutritional quality of sous vide or traditionally processed fish: influence of fat content.

Sous vide technology, which implies vacuum packaging, pasteurization and storage at a chill temperature, also implies a challenge to obtain a balance between an extended shelf life and microbiological safety of the product with a fresh-like appearance and a high nutritional value. The aim of this work was to determine the effect of fat content of two fish species (salmon and trout) on survival of mesophilic, psychrotrophic, Enterobacteriaceae, Micrococaceae and anaerobes during sous vide cooking and their control during chilled storage for 3, 20 and 45 days. Proximate and fatty acid composition was also determined using a traditional cooking method. Analyses were undertaken comparatively with the same culinary technique for sous vide and traditionally cooked fish. Higher fat levels in all products resulted in fewer microbial reductions. In order to establish adequate pasteurization (temperature/time) combinations for the assurance of microbial quality and shelf life of sous vide processed fish, fat content and fatty acid composition of food should be considered