Cheese Making with Rennet

  Calf rennet is the most prevalent coagulant in the cheese making industry and is regarded as the standart rennet against which alternative coagulants are measured.The rennet extracted from the fourth stomach of the suckling calf contains chymosin and pepsin.Thus variations in the ratio of chymosin to pepsin can be expected depending on the age of the calf at slaughter.

Standart calf rennet is supplied by manufacturers as a pure solution of rennet enzymes with added salt,propylene,glycol and sodium benzoate as preservatives,together with permitted color and flavour.In warm countries where liquid rennet will not keep powdered  or paste rennets are available.

Rennet extract is introduced into milk in a diluted form,with cold tap water,to disperse it more uniformly.The milk must than remain quiescent until coagulated,for even slight vibrations result in hindrance of the development of a homogeneous,compact curd.

The amount of rennet added to cheese milk will be governed by the type of cheese being  manufactured.The specific recipe will also dictate the temperatıre and acidity of the milk necessary to produce a coagulum ready for cutting within a specified time.

The quantity of rennet used depends on the cheese being manufactured and other factors such as seasional variation in the chemical quality of milk and variations in processing conditions.

Rennet rapidly loses activity if stored diluted for long periods.Light too causes deterioration and thus rennet must be stored in light-proof containers.

The actual time from rennet addition to optimal coagulum cutting varies depending on the recipe.The actual point of cutting id related to curd firmness and measurement of the optimal value is presently a subject of considerable interest within the industry.