Effect of the addition of Micrococcus sp INIA 528 milk cultures and curds on cheese proteolysis and lipolysis

Semi-hard cheeses were manufactured at laboratory scale from milk inoculated at 2% with a fresh culture of Micrococcus sp. INIA 528, or by mixing high enzymatic activity (HEA) curds, made with this strain, at 10 or 20% with standard curds. Micrococci counts increased slightly during the first hours of manufacture and decreased gradually thereafter. Increases in proteolysis values of 63% in cheese from milk inoculated with micrococci, and of 72% in cheese made with 20% HEA curds, with respect to control cheese were recorded after ripening for 14 days. Tributyrin esterase was detected from day 1 in cheese made from milk inoculated with micrococci and in cheeses with added HEA curds. However, only the addition of HEA curds enhanced lipolysis significantly, with a maximum increase of 85% for cheese made with 20% HEA curds after 14 days. Milk inoculation with micrococci and addition of HEA curds showed to be useful tools for the acceleration of cheese ripening.