The Surprising Use of Egg-Derived Ingredients in Cheese
While most cheese is made from milk, cultures, salt, and rennet, some varieties contain an unexpected ingredient derived from eggs. This is not a standard component but a specific additive used in particular cheeses. The ingredient is called lysozyme, an enzyme extracted from hen egg whites. Its inclusion is primarily to act as a preservative, preventing the growth of unwanted bacteria that can cause defects like "late blowing" in aged cheeses. For individuals with egg allergies, or those strictly avoiding animal products, identifying cheeses that contain this additive is essential.
What is Lysozyme and Why is it in Cheese?
Lysozyme, designated as food additive E1105 in Europe, is a natural antimicrobial enzyme found in hens' egg whites. Its purpose in cheese production is to combat certain bacteria, specifically Clostridium tyrobutyricum, which can spoil the cheese during the aging process. By inhibiting this bacteria, lysozyme helps to ensure a consistent texture and flavor in the final product.
One of the most famous examples of a cheese that permits the use of lysozyme is Grana Padano. Unlike its well-known counterpart, Parmigiano Reggiano, which strictly forbids additives, the PDO (Protected Designation of Origin) specification for Grana Padano allows for the addition of egg white lysozyme. This is a key distinction for consumers to understand.
Traditional Rennet vs. Microbial Rennet
Most people's concerns about animal products in cheese revolve around rennet, the enzyme used to coagulate milk and form curds. Traditionally, rennet is sourced from the stomach lining of young calves, making those cheeses unsuitable for vegetarians. However, the cheese industry has evolved significantly, and there are several alternatives that do not involve animal products:
- Microbial Rennet: This is an enzyme harvested from the fermentation of a specific fungus, Rhizomucor miehei, and is widely used in commercial cheese production. Cheeses made with microbial rennet are suitable for vegetarians.
- Vegetable Rennet: Derived from certain plants, such as the thistle or fig tree, this rennet is less common but still used to make specific types of cheese.
- Acid Coagulation: Many soft cheeses, including mozzarella, ricotta, and paneer, do not use rennet at all. Instead, an acid like vinegar or lemon juice is used to curdle the milk.
It is important to remember that a cheese made with microbial or vegetable rennet is vegetarian, but that does not automatically guarantee it is egg-free if other additives are used. For this reason, checking the ingredients is still the most reliable method.
How to Identify Cheese Containing Egg Additives
For consumers needing to avoid eggs, the responsibility falls on checking the product labeling. Manufacturers who use egg-derived lysozyme are required to list it as an allergen.
- Look for Key Terms: Search the ingredients list for the words "lysozyme" or "egg white lysozyme".
- Check the E-number: In regions where applicable, the additive may be listed as E1105.
- Understand Brand Differences: Be aware that variations within a cheese type can exist. For example, while Grana Padano can contain lysozyme, not all brands will, so reading the specific label is crucial.
A Comparison of Common Cheese Types
To better illustrate which cheeses are generally safe and which require a closer look, here is a comparison table based on common ingredients and potential additives.
| Cheese Type | Typical Ingredients | Uses Egg-Derived Lysozyme? | Typically Vegetarian? (Microbial/Vegetable Rennet) | Considerations for Egg Allergies |
|---|---|---|---|---|
| Grana Padano | Cow's milk, salt, rennet, lysozyme | Sometimes (Permitted Additive) | No (Often Uses Animal Rennet) | Check label for lysozyme (E1105) |
| Parmigiano Reggiano | Cow's milk, salt, animal rennet | No (Prohibited Additive) | No (Requires Animal Rennet) | Safe (No Egg Additive) |
| Mozzarella | Cow's or buffalo milk, acid or rennet | No (Acid-coagulated varieties) | Yes (If microbial rennet or acid is used) | Generally Safe |
| Ricotta | Whey, milk, acid | No (Acid-coagulated) | Yes (Acid-coagulated) | Safe (Egg-free production) |
| Cheddar | Cow's milk, salt, cultures, rennet | No (Not Standard) | Varies (Check for microbial rennet) | Generally safe, but check for microbial rennet |
| Feta | Sheep's or goat's milk, cultures, rennet | No (Not Standard) | Varies (Check for microbial rennet) | Generally safe, check for rennet source |
Conclusion: The Importance of Label Awareness
Ultimately, the question "Does any cheese have eggs?" can be answered with a qualified "yes." While the practice is not widespread, certain cheeses do use an egg-derived enzyme as a preservative. For the vast majority of cheese varieties, including many fresh and vegetarian options, eggs are not part of the recipe. The key takeaway for anyone with an egg allergy or dietary restriction is the importance of diligence. Always check the ingredient label, and for traditional, aged European cheeses like Grana Padano, be especially aware of the potential presence of lysozyme. By understanding the specific ingredients and production methods, you can confidently navigate the world of cheese and make safe choices for your diet.
For further information on the safety evaluation of lysozyme as a food enzyme, you can consult reports from regulatory bodies EFSA safety evaluation of lysozyme.
