Milk-Clotting Enzymes and Cheese Chemistry

Enzyme Technology – Dairy Industry Applications

“…This enzyme is released by the mucous membranes of the stomachs of hogs and cows and is secreted as a catalytically inactive pepsinogen with a molecular weight of 40 400 Da. Pepsin is stable in neutral and slightly alkaline solutions, but undergoes reversible denaturation above 55 °C at pH 7.0 and at room temperature at pH 11.0 [19]. Although pepsin can clot milk, its use has a tendency to lead to higher losses of milk fat because the resulting curd has a more open, looser structure than that formed with chymosin; the cheese produced using pepsin also has a softer body than desired.…”

Role of Clay Substrate Molecular Interactions in Some Dairy Technology Applications

“…Many other fungi and bacteria cultures originating from soils, butter, milk, and other sources were found to favor the formation of MCE displaying a wide range of clotting-toproteolytic activity ratio of milk (MCA/PA) [37]. Other more or less successful attempts were carried out [38][39][40] more particularly on a variety of plant-deriving MCE in spite of their detrimental excessive proteolytic activity that confers bitter flavor to the manufactured cheeses [36]. In addition, in spite of their numerous advantages, the of use plant-deriving MCE still remains limited, due to potential food contamination risks by chemicals employed in the extraction process.…”

Cheese

“…A variety of methods have been developed to monitor gel firmness including light scattering measurement, ultrasound, mechanical measurement of gel strength and heat flow as influenced by gel formation (BROWN and ERNSTROM, 1988). Most have been used in laboratory and pilot plant settings; a few have been used under commercial conditions to indicate the desired point of cutting the milk gel.…”