Efeito da relação caseína/gordura do leite nas propriedades do queijo Prato

Abstract

Prato cheese is a typical Brazilian cheese, with high consumption possibly due to its functional properties. The objective of this work was to evaluate the effect of the casein / fat ratios 0.68, 0.72 and 0.76 on the physical-chemical, sensory, texture and functional properties of Prato cheese. The cheeses from the four repetitions, produced with the different casein / fat ratios, were evaluated after 2 days of manufacture in terms of their physical-chemical composition and manufacturing performance. The functional properties of melting, feasibility, free oil and pH, water activity, proteolysis rates, evolution of the texture and color profile were evaluated over four maturation times (2.15, 30 and 45 days). Microbiological analysis and sensory analysis were evaluated after 30 days of maturation. The variations in the casein / fat ratios studied did not significantly change (P> 0.05) the physical-chemical characteristics of the cheeses, including pH and Aw, evaluated over the maturation time. The proteolysis extension and depth indices did not change significantly (P> 0.05) between the relationships, but increased throughout maturation. There was no influence on the current and adjusted cheese yield (P> 0.05), however the use of the casein / fat ratio 0.68 increased the recoveries of protein and fat and, consequently, there was less loss of these to the serum, in comparison with the casein / fat ratio 0.76 (P <0.05). Cheeses manufactured with a 0.68 casein / fat ratio provided greater melting capacity and free oil release (P <0.05). The studied casein / fat ratios did not influence the cheese slicing. There was also no interference in hardness, adhesiveness, cohesiveness, elasticity, and cut (P> 0.05). Only chewability was lower in cheeses produced with a 0.68 casein / fat ratio (P <0.05). The casein / fat ratios studied did not significantly change the color of the cheeses between treatments (P> 0.05), only in relation to time (P <0.05). In the consumer acceptance test, no difference was detected between treatments for the appearance, aroma, flavor, texture and overall impression of Prato cheeses (P> 0.05). Thus, it is concluded that for the manufacture of a Prato cheese that presents a lower melting and oil release, the casein / fat ratio 0.76 is the most recommended and for the manufacture of a Prato cheese that presents a greater melting and release of oil, the casein / fat ratio of 0.68 should be chosen. The definition of the casein / fat ratio to be used depends on the product desired by the dairy industry. For this, it becomes necessary, first, to implement casein analysis in the industry laboratory. This is a simple analysis, which does not require investments in expensive equipment and reagents. From this, the industry will be able to standardize the manufacture of Prato cheese according to the desired functional properties to serve different audiences and segments, either by a cheese that melts more and releases more free oil or by one that melts less and releases less free oil.