What is Rennet in Cheese? A Comprehensive Guide

When it comes to cheese production, rennet is a crucial ingredient that plays a vital role in the coagulation process. Rennet is an enzyme responsible for causing the milk to coagulate and turn into junket, which is cut, and then separated into curds and whey. A vital part of cheese making cheese. With rennet, we can produce many types of cheese that we know and love. In this blog, we will discuss rennet, its types, how it works, and its role in cheese production.

What is Rennet?

Rennet is an enzyme found in young mammals' stomachs, such as calves, lambs, and goats. The enzyme is responsible for curdling the milk in the stomach to aid digestion. This digestive process is essential for the young mammal to get the necessary nutrients from their mother's milk. The rennet enzyme has been used for centuries in cheese production to curdle the milk, creating curds that are pressed and aged to create a wide variety of cheese.

Types of Rennet

Traditionally, rennet was sourced from the stomach of young mammals. Still, with the rise of vegetarianism, and the need for greater consistency in cheese production, rennet from non-animal sources has become more popular. The three primary types of rennet are:

1. Animal Rennet: This type of rennet is sourced from the stomach of young mammals such as calves, lambs, and goats.
2. Microbial Rennet: This type of rennet is produced by fermenting a fungus called Rhizomucor miehei or Rhizomucor pusillus. It is suitable for vegetarians and is widely used in cheese production.
3. Vegetable Rennet: This type of rennet is derived from plants such as thistle, fig leaves, and nettles. It is an excellent alternative for vegetarians and is also used in cheese production.

How Rennet Works

When milk is combined with rennet, it triggers the coagulation process by breaking down the proteins in the milk, specifically casein, into curd. The curd is then separated from the whey, which is the liquid that remains after the milk coagulates. The resulting curd is used to make cheese, and the whey is used to produce other dairy products.

The amount of rennet used in cheese production varies depending on the type of cheese being produced, the milk used, and the desired texture and flavour of the final product. Cheese producers may also use a combination of different types of rennet to achieve the desired result.

Summary of the Role of Rennet in Cheese Production

In conclusion, rennet is a crucial ingredient in cheese production that plays a vital role in coagulation. It is an enzyme that causes milk to curdle, resulting in curd, which is then used to make cheese. Different types of rennet are available, including animal, microbial, and vegetable, each with unique characteristics and advantages. The type and amount of rennet used significantly affect the texture, flavour, and consistency of the final cheese product. Cheese producers carefully control the coagulation process to achieve the desired result.