What does rennin mean?
Rennin is an enzyme that makes milk coagulate by breaking down the surface of casein, the principal protein in milk. It occurs naturally in the stomachs of calves and other young ruminants and was traditionally obtained from the stomach lining of calves for cheese making. When added to milk, it causes the formation of curds, which can then be separated from the whey and matured into cheese. The substance is also known scientifically as chymosin, while rennet commonly refers either to the enzyme itself or to a preparation containing it. Although recombinant versions of chymosin are widely used in commercial cheese production, rennin remains an important term in dairy science and the history of cheesemaking. It should not be confused with renin, a different enzyme involved in controlling blood pressure.
nounAn enzyme found in the stomach of calves and other young ruminants that coagulates the casein in milk. It is also called chymosin and is used in traditional cheese making.
- An enzyme that coagulates milk by acting on casein, obtained especially from the fourth stomach of calves and used in cheese making.
"The rennin in the calf's stomach caused the milk to coagulate into curds."
"The curd farmer added a small amount of rennin to the milk."
"Rennin rapidly coagulated the milk, producing a firm curd."
Rarely used in the plural; rennin is normally treated as an uncountable name for the enzyme.
"Researchers compared the activity of the two rennins under different temperature conditions."
Your cheese may have begun with a calf's stomach: rennin was traditionally extracted from the stomach lining of young calves to coagulate milk.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does rennin come from?
Rennin is an English scientific coinage from the late 19th century for the milk-coagulating substance associated with rennet and the stomachs of calves. Its alternative name, chymosin, was adopted in scientific usage for the enzyme itself. The enzyme's long-standing importance in cheesemaking helped preserve both terms in dairy vocabulary.
How rennin is actually used
Rennin is primarily a technical term in biochemistry, dairy science, and food production. It is also called chymosin; in general food usage, the preparation made from the stomach lining of calves is usually called rennet.
Easily confused with rennin
Rennin is the milk-clotting enzyme traditionally used in cheese making, whereas renin is an enzyme involved in regulating blood pressure and fluid balance.