What is Natamycin and How is it Used in Cheese?
Natamycin, also known as pimaricin (E235), is a naturally occurring antifungal preservative produced by the bacterium Streptomyces natalensis. It is a popular choice for manufacturers seeking a "clean label" preservative because it is derived from a natural source. The primary function of natamycin is to inhibit the growth of molds and yeasts on the surface of foods, including cheese.
Unlike traditional preservatives that are soluble and can penetrate deep into food, natamycin's low solubility means it remains on the surface where mold and yeast growth typically occurs. This makes it an ideal surface treatment for cheeses, especially those with a high surface area, like shredded varieties. Manufacturers apply a diluted natamycin solution to the surface of cheese blocks before they are shredded and packaged. This creates a protective, antimicrobial layer that prevents spoilage throughout the product's shelf life.
The Reason for Natamycin in Shredded Cheese
Shredded cheese, by its very nature, is highly susceptible to mold growth. The shredding process dramatically increases the cheese's surface area, exposing more of it to air and potential fungal contamination. Without a preservative, shredded cheese would have a very short shelf life once packaged. Natamycin is used specifically to combat this problem. It extends the cheese's freshness, minimizes food waste, and ensures the product remains aesthetically pleasing and safe for consumption.
Common Applications of Natamycin in Cheese
Beyond shredded varieties, natamycin is applied to many other types of cheese products to prevent mold. The application method depends on the cheese type:
- Hard and Semi-Hard Cheeses: Surface spraying is used on cheeses like cheddar or Swiss to create a protective barrier on the exterior during aging.
- Soft Cheeses: Cheeses such as brie or feta are often dipped in a natamycin solution to cover the delicate rind.
- Processed Cheese Products: Natamycin can be incorporated into cheese sauces or other processed items in some jurisdictions to inhibit spoilage.
Is Natamycin Safe to Eat? Regulators Weigh In
Major food safety organizations worldwide have approved the use of natamycin as a food preservative at controlled levels. Its safety is backed by extensive scientific review and regulatory oversight from bodies like the U.S. Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA).
- Poor Absorption: Natamycin is very poorly absorbed by the body when ingested. Studies show that a significant portion passes through the digestive system and is excreted without being absorbed.
- Low Toxicity: At the low concentrations used in food production, natamycin is considered safe for human consumption. This is a key reason regulatory bodies have approved its use.
- Minimal Impact on Flavor: Because it primarily remains on the surface of the cheese, natamycin does not affect the flavor, texture, or color of the product. It specifically targets harmful fungi without inhibiting the beneficial bacteria vital for cheese fermentation and development.
Natamycin vs. Other Cheese Preservatives
To better understand why natamycin is often chosen, here is a comparison with other common cheese preservatives like sorbates and nisin.
| Feature | Natamycin (E235) | Sorbates (e.g., Potassium Sorbate) | Nisin (E234) |
|---|---|---|---|
| Type | Natural antifungal (polyene macrolide) | Synthetic antifungal (derived from sorbic acid) | Natural bacteriocin |
| Mechanism | Binds to fungal cell membranes, inhibiting mold and yeast. | Disrupts fungal and some bacterial growth by inhibiting certain enzymes. | Kills gram-positive bacteria by creating pores in cell membranes. |
| Target | Specifically effective against molds and yeasts. | Effective against molds, yeasts, and some bacteria. | Specifically effective against bacteria, like Listeria and Clostridium. |
| Solubility | Poorly soluble in water, remaining on the surface. | Highly water-soluble, can migrate into the cheese matrix. | Water-soluble. |
| Primary Use | Surface treatment for mold and yeast prevention. | Added to cheese spreads, sauces, and some grated cheeses. | Used in processed cheese slices and high-moisture cheeses to control bacteria. |
| Flavor Impact | Minimal to none, stays on the surface. | Can potentially cause flavor changes, particularly during storage. | Minimal, if any, when used in combination. |
How to Find Natamycin in Your Shredded Cheese
Determining if shredded cheese contains natamycin is straightforward. Food labeling regulations in many countries require that the presence of preservatives be disclosed on the ingredients list. Consumers can check the product packaging for terms like “natamycin,” “pimaricin,” or its European food additive number, “E235”. In the United States, regulations also permit natamycin in a dry mix with an anti-caking agent, and this may be listed as such on the ingredients list.
Some manufacturers of premium or organic shredded cheese may choose not to use natamycin, instead relying on other packaging techniques or accepting a shorter shelf life. For those seeking to avoid it, reading the ingredient list is the best approach.
Conclusion: A Common Additive for Shelf Life
In summary, the question of whether shredded cheese has natamycin in it can be answered with a definitive yes for many commercial products. This naturally derived, surface-active antifungal is a common and effective tool used by manufacturers to prevent mold and yeast growth, thereby extending the product’s freshness and safety. Its poor solubility ensures it remains on the surface, preserving the flavor profile of the cheese. Food safety regulators worldwide have deemed it safe for consumption at approved levels. For consumers, checking the ingredient label for “natamycin” or “E235” is the best way to confirm its presence and make an informed purchasing decision.
Here is an excellent resource for learning more about food additives and safety.
