Rennet And Natamycin

Rennet is a complex of enzymes, most commonly chymosin, traditionally sourced from the stomach lining of young calves. Today, microbial or fermentation-produced chymosin (FPC) are widely used alternatives, made by genetically engineered microorganisms. Rennet's primary role is to coagulate milk proteins, forming curds for cheesemaking.

Rennet is essential in the production of most cheeses, causing milk to thicken and separate into curds and whey. Natamycin is a natural antifungal agent produced by fermentation of the bacterium *Streptomyces natalensis*. It is used as a surface treatment for cheeses and other foods to prevent mold growth.

Both rennet and natamycin are approved for use in the United States. Rennet, especially FPC, is generally recognized as safe (GRAS) by the FDA. Natamycin is permitted as a food additive for surface treatment of cheese and other foods. International bodies like JECFA and EFSA have evaluated these substances. Typical intakes are considered safe.