The Surprising Animal-Derived Ingredient
For vegetarians, cheese can be a primary source of protein and flavor, but a closer look at the cheesemaking process reveals that not all cheese is vegetarian-friendly. The most common and surprising culprit is traditional Parmesan cheese, officially known as Parmigiano-Reggiano. The reason it is not vegetarian stems from the use of animal rennet, a set of enzymes derived from the stomach lining of young calves, lambs, or kids.
What is Animal Rennet?
Rennet is a coagulating agent essential for separating milk into solid curds and liquid whey, the foundational step in making most cheeses. Historically, this enzyme was obtained from the fourth stomach (abomasum) of young, milk-fed ruminant animals. In the traditional production of Parmigiano-Reggiano, calf rennet is a mandatory ingredient, as specified by its Protected Designation of Origin (PDO) status in Italy. This means that for a cheese to be legally called Parmigiano-Reggiano, it must follow this traditional method, including the use of animal rennet. This requirement is the core reason why the authentic Italian cheese is not vegetarian.
The Cheesemaking Process and Coagulation
The cheesemaking process for Parmesan begins with heating unpasteurized cow's milk. A whey starter culture is added, followed by the addition of animal rennet. This enzyme acts on the milk's proteins, specifically kappa-casein, causing the milk to curdle and form a solid gel. The cheesemaker then breaks the curd into small granules, cooks it, and lets it settle. The curds are collected, pressed into molds, brined, and then aged for a minimum of 12 months. This long aging process, influenced by the properties of the animal rennet, gives Parmigiano-Reggiano its signature nutty flavor and granular texture.
The Difference Between 'Parmigiano-Reggiano' and 'Parmesan'
It's important for vegetarians to distinguish between authentic Parmigiano-Reggiano and other hard cheeses labeled simply as "parmesan". The term "Parmigiano-Reggiano" is legally protected and guarantees the use of animal rennet. However, in many countries, cheesemakers can use the term "parmesan" or "parmesan-style cheese" for similar hard cheeses that are made with non-animal rennet. These vegetarian-friendly versions use alternative coagulants, such as microbial or vegetable rennet.
Types of Non-Animal Rennet
Cheesemakers now have several vegetarian alternatives to animal rennet:
- Microbial Rennet: This type is derived from molds, fungi, or yeast and is widely used in commercial cheesemaking today. The enzyme produced is genetically identical to the one found in calves but is fermented in a lab, making it economical and reliable.
- Plant-Based Rennet: Enzymes from certain plants, such as artichokes, thistles, and fig leaves, have coagulating properties. This type is less common in mass production but is used in some traditional and artisanal cheeses, particularly in parts of Spain and Portugal.
- Fermentation-Produced Chymosin (FPC): This is a form of microbial rennet created using genetic engineering to produce a highly pure chymosin enzyme. It is a very common coagulant in modern cheesemaking and is suitable for vegetarians.
Navigating the Dairy Aisle: How to Find Vegetarian Cheese
Reading the label is the most crucial step for a vegetarian. Look for phrases like "microbial rennet," "vegetable rennet," or "suitable for vegetarians" on the packaging. Alternatively, a kosher certification on cheese often indicates it is free of animal rennet. Some brands that explicitly label their parmesan-style cheeses as vegetarian include BelGioioso, Organic Valley, and Trader Joe's' grated parmesan. Stores like Whole Foods also carry clearly labeled vegetarian options.
Comparison of Traditional and Vegetarian Parmesan-style Cheese
| Feature | Traditional Parmigiano-Reggiano | Vegetarian Parmesan-style Cheese |
|---|---|---|
| Rennet Type | Animal (Calf) | Microbial, Plant, or FPC |
| Origin | Specific regions of Italy (PDO) | Can be produced anywhere |
| Flavor | Nutty, fruity, complex, umami | Generally similar, some differences possible |
| Texture | Hard, grainy, crystalline | Often similar to the traditional version |
| Vegetarian? | No | Yes, if labeled with non-animal rennet |
Creative Alternatives for a Vegetarian Diet
If finding a labeled vegetarian option is challenging, or if you prefer a different flavor profile, several excellent alternatives exist. For a dairy-free and nutty topping, consider a sprinkle of nutritional yeast. Another great option is a homemade vegan parmesan blend using nutritional yeast, hemp seeds, and spices. For a different type of cheese with a similar salty, hard texture, some opt for cheeses like Old Winchester, which is explicitly made with vegetarian rennet. Other options include Grana Padano (though some may use animal rennet, so check the label) or Pecorino Romano, though this also traditionally uses animal rennet. Always check the specific product label. For a comprehensive guide to vegetarian cheese, you can consult a trusted source like the Vegetarian Times.
Conclusion
While the discovery that traditional Parmigiano-Reggiano is not vegetarian can be disheartening for some, it is crucial for a vegetarian diet. The presence of animal-derived rennet is a non-negotiable part of the authentic product's recipe due to its legal PDO status. Fortunately, consumers have many excellent vegetarian-friendly alternatives to fill the void. By simply reading labels and understanding the different types of coagulants used, vegetarians can confidently continue to enjoy delicious, cheesy toppings without compromising their dietary principles.
Where to find more information
For more details on cheeses that are suitable for vegetarians, check out this guide from Bon Appétit: What Do You Mean Parmesan Isn't Vegetarian?.
