Efeito do uso do dióxido de carbono (CO2) na fabricação do queijo prato

Abstract

The preacidified milk with injection of CO2 (carbon dioxide) used for cheesemaking can bring technological and economic benefits to the pilot scale. The aim of this study was to evaluate technological effects of the use of CO2 dissolved in the milk after pasteurization process to make Prato cheese. The experiments were carried out with CO2 incorporation in pasteurized milk by CO2 injection under maximum pressure of 25 psi at 8° C until to reach pH 6.00, besides the control cheeses (without CO2 injection). This procedure was performed four times. The cheese making times, physicochemical properties, cheese yield, changes during the storage time, sensory acceptability, preference and microstructure analysis were determined in both cheeses. It was observed that the CO2 injection reduced Prato cheeses pH, wich showed significant reductions in coagulation and total cheeses making times. The CO2 injection also reduced the moisture and the percentage of fat loss in the whey serum, did not affect the lactic acid fermentation, and did not change the microbial count. Prato cheese treated with CO2 did not show changes in the proteolysis indexes. Due to their larger whey loss and more compact microstructure. The cheese showed higher firmness and brittleness when compared to the control cheese. Protein matrix porosity and cheese draining also increased. There was no significant difference (p> 0.05) in preference and sensory acceptability among treatments.