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see rennetrennet,
substance containing rennin, an enzyme having the property of clotting, or curdling, milk. It is used in the making of cheese and junket. Rennet is obtained from the stomachs of young mammals living on milk, especially from the inner lining of the fourth, or true,
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(also chymosin), a proteolytic enzyme produced by the mucous membrane of the abomasum, or fourth stomach, of young ruminants. Rennin, in the form of abomasal extract, has long been used for coagulating milk in cheese-making. It is synthesized as an inactive precursor, renninogen, which is converted into rennin in an acid medium at pH < 5.0. The starting substrate for rennin is the milk protein κ-casein, which under the action of rennin loses the ability to stabilize the casein micelles. Rennin is obtained in crystalline form; its molecule is composed of a polypeptide chain (molecular weight ~ 34,000) in which dicarboxylic amino acids predominate. Rennin resembles pepsin in many of its properties.


An enzyme found in the gastric juice of the fourth stomach of calfs; used for coagulating milk casein in cheesemaking. Also known as chymosin.
References in periodicals archive ?
Organic Valley, a major producer of organic cheeses in the United States, told us, "Historically, rennet was extracted from calf stomachs by killing the calves, cutting the stomach into strips, scraping the lining to remove surface fat, stretching it onto racks where moisture is removed, grinding it, and then finally mixing it with a salt solution until the rennin is extracted.
Casein (caseinate) is a milk protein that coagulates with the addition of rennin and is the foundation of cheese.
An enzyme in calves' stomachs, called rennin, converts milk into curds (white lumps) and whey (a thin, cloudy liquid).
It's an exact copy of rennin, the animal enzyme traditionally used to coagulate milk.
In 1990, FDA approved the first bioengineered enzyme, rennin, which traditionally has been extracted from calves' stomachs for use in making cheese.
Effects of puerarin on blood pressure and plasma rennin activity in spontaneously hypertensive rats.
The hormones secreted during "fight or flight" reactions all work to raise blood pressure: rennin, epinephrine, aldosterone, and norepinephrine.
Inhibition of the Rennin Angiotensin System (RAS) is an integral component of the modern management of HF with LV systolic dysfunction.
Angiotensin converting enzyme inhibitors remains the first choice for the inhibition of the rennin angiotensin system and ARBs are standard alternative in ACE I intolerant patients.
The company says Rasilez (aliskiren), an oral rennin inhibitor, would be the first new class of high blood pressure medicine available in more than 10 years.