What is Cellulose and Why Is It in Grated Cheese?
Cellulose is a plant-based fiber found in the cell walls of virtually all plant matter, including fruits, vegetables, and trees. In its food-grade form, it is a purified, fine white powder that is tasteless and odorless. The so-called "wood pulp in cheese" scandal that grabbed headlines is a bit of a misnomer; while wood pulp is a primary source for industrial cellulose, the final product is a food-grade fiber, not sawdust. For the food industry, cellulose is a versatile and inexpensive ingredient used for several functional purposes:
- Anti-caking Agent: This is its most important function in grated cheese. Cellulose coats the individual shreds of cheese, preventing them from sticking together and clumping into a solid mass inside the container. Without it, the cheese would quickly become one moist, unusable block.
- Moisture Absorption: Cellulose helps absorb excess moisture, which not only prevents clumping but also extends the product's shelf life.
- Bulking Agent: As a dietary fiber with no caloric value, cellulose can add bulk and texture to foods, helping to reduce costs for manufacturers.
The “100% Grated Parmesan” Controversy
In 2016, headlines exploded with news that some brands labeled as "100% grated parmesan cheese" contained significant amounts of cellulose, leading to a fraud investigation by the FDA. While the FDA allows a small amount of cellulose (typically 2-4%) to function as an anti-caking agent, tests revealed that some brands far exceeded this limit, with one brand reportedly testing at 8.8% cellulose. This controversy highlighted the deceptive labeling practices of some companies, who were using cellulose not just to prevent clumping but also as a cheap filler. The core issue for many consumers was not the safety of the ingredient but the misleading claim of a product being "100% cheese" when it was not.
Is Food-Grade Cellulose Safe to Consume?
Yes, food-grade cellulose is considered safe for consumption by regulatory bodies like the FDA, which has classified it as "Generally Recognized As Safe" (GRAS). It is an insoluble dietary fiber that passes through the human digestive system largely intact, similar to the fiber found in fruits and vegetables. In fact, insoluble fiber is a healthy and necessary part of a balanced diet, aiding in digestion and promoting regular bowel movements. The primary concern for consumers should not be safety but transparency and product quality. Overconsumption of any fiber, including cellulose, can potentially lead to digestive discomfort such as bloating or gas, but this is unlikely from the small amounts found in grated cheese.
Grated Parmesan vs. Block Parmigiano-Reggiano
When choosing a parmesan cheese, understanding the difference between commercial grated parmesan and an authentic block of Parmigiano-Reggiano is crucial. The presence of cellulose is one of the key differentiators.
A Comparison of Grated and Block Parmesan
| Feature | Commercial Grated Parmesan (U.S.) | Block Parmigiano-Reggiano (Italy) |
|---|---|---|
| Cellulose Content | Contains food-grade cellulose as an anti-caking agent. | 0% cellulose or any other additives. |
| Purity | Often a blend of different cheeses, fillers, and additives. | A 100% natural product made only from milk, salt, and rennet. |
| Flavor and Texture | Milder, less complex flavor; powdery, uniform texture. | Nutty, rich, and complex flavor profile; hard, crystalline texture. |
| Cost | Typically less expensive due to the use of fillers. | More expensive due to strict production standards and aging requirements. |
| Shelf Life | Longer shelf life due to preservatives and anti-caking agents. | Shorter shelf life after grating; best stored in block form. |
| Convenience | Highly convenient; ready to use out of the container. | Requires grating at home, which takes extra time and effort. |
How to Find Cellulose-Free Parmesan
If you want to avoid cellulose in your cheese, there are two simple and reliable methods:
- Buy a block and grate it yourself. This is the surest way to guarantee your cheese is 100% pure. A wedge of cheese like Parmigiano-Reggiano will list only milk, salt, and rennet as ingredients.
- Read the ingredient label carefully. Check for "powdered cellulose," "cellulose," or similar names like "microcrystalline cellulose". While most pre-grated products contain it, some specialty brands may offer alternatives. However, grating your own is the only way to be completely certain.
The Verdict: Grated Parmesan and Cellulose
Ultimately, whether grated parmesan containing cellulose is a problem for you depends on your priorities. For many, the convenience and lower cost of pre-grated cheese outweigh the fact that it contains a harmless, fiber-based additive. For others, the purity of a product and the richer flavor of real, additive-free cheese are more important. The good news is that cellulose is not dangerous. The bad news is that the labeling can be misleading. Consumers who want truly pure parmesan cheese should simply opt for a block and a grater. For those who prioritize convenience, checking the label and being aware of what you're eating is the best course of action. Regardless of your choice, awareness about ingredients like cellulose empowers you to make informed decisions about the food you consume.
Learn more about food additives and regulations at the Center for Science in the Public Interest.
