Chymosin Rennet - What is it?

Chymosin Rennet: A Modern Alternative to Traditional Animal Rennet in Cheesemaking

When talking about rennet, traditionally it is sourced from the stomachs of young ruminant animals (calfs), but advancements in biotechnology and the creative minds of the cheese industry have introduced Chymosin rennet as an accessible alternative. Let's dive into why Chymosin rennet has become a favored choice among our customers and cheesemakers, here at New England Cheesemaking Supply Co.

Understanding Rennet and Its Role in Cheesemaking

Rennet is a complex set of enzymes, with the chymosin enzyme being its key component. These enzymes coagulate milk, separating it into solid curds (casein protein) and liquid whey (whey protein)—a fundamental step in cheese production. Historically, rennet was extracted from the stomach linings of unweaned calves. Their diets consist solely of milk, making their stomachs rich in chymosin enzymes which break down milk, specifically. Other enzymes begin to develop (pepsin) once grass is introduced into their diet. This traditional source, while effective, can cause limitations in supply and raises ethical concerns for certain artisan cheesemakers and their customers.

The Emergence of Chymosin Rennet

To address these challenges, scientists have worked to develop methods to produce the chymosin enzyme through fermentation. By inserting the gene responsible for chymosin production into microorganism hosts like bacteria, fungi, or yeasts, these organisms can produce chymosin during fermentation. The resulting enzyme, known as fermentation-produced chymosin (commonly called FPC for short, or just plain 'Chymosin Rennet'), is virtually identical to its animal-derived option but is produced without the need for animal slaughter.

Just Some of the Advantages of Chymosin Rennet

1. Consistency and Purity: Chymosin rennet offers a high degree of purity, containing primarily chymosin without other enzymes that are present in traditional animal rennet. This purity leads to more consistent coagulation and cheese quality. Other rennet options can have enzymes that do not specifically work with just the casein proteins, causing off flavors and textures in aged cheese.
2. Vegetarian and Ethical Considerations: Since Chymosin is produced without any animal involvement, it aligns with vegetarian diets and addresses the more ethical concerns related to animal welfare. This makes cheeses produced with Chymosin suitable for vegetarians and those adhering to kosher or halal dietary restrictions.
3. Supply Stability: Relying on microbial fermentation ensures a steady and scalable production of chymosin, avoiding supply issues associated with animal-derived rennet.
4. Economic Efficiency: The production of Chymosin Rennet can be more cost-effective, as it doesn't depend on the livestock industry. This efficiency can lead to lower costs for cheesemakers, which is quite helpful for a good amount of farmers and homesteaders.

GM...Oh?

Chymosin rennet is commonly classified as non-GMO because the final purified enzyme does not retain any genetically modified components, even though it is originally produced using genetically modified microorganisms. Producers ensure no GMO material is in this product due to the strict legal regulations surrounding labeling, and consumer concerns.

Addressing Other Potential Concerns

Some traditionalists argue that cheeses made with Chymosin rennet may lack the depth of flavor found in those made with animal rennet. However, studies and blind taste tests have shown that Chymosin rennet performs comparably to animal rennet in both flavor development and texture. Additionally, regulatory bodies worldwide have evaluated and approved Chymosin rennet for use in food production, underscoring its safety and efficacy.

Try the Chy-mosin!

We have found that Chymosin rennet, produced through fermentation, stands as a remarkable alternative to traditional animal rennet. It offers consistency, aligns with ethical and dietary preferences, ensures a stable supply, and supports economic efficiency in cheesemaking. As the industry continues to evolve, Chymosin rennet exemplifies how innovation can honor tradition while embracing modern values and technologies. Check out our item page for our Chymosin Rennet options here.

Thank you for reading!