Understanding Processed Cheese Ingredients
Processed cheese is more than just melted natural cheese. It is a highly engineered product designed for specific functional properties, such as a long shelf life and a flawless, non-separating melt. Its ingredient list reveals a combination of natural and added components that work together to achieve these goals.
The Foundational Cheese Base
At its core, processed cheese must contain natural cheese, although the amount can vary depending on the specific product's classification (e.g., "processed cheese," "processed cheese food," or "processed cheese spread"). Manufacturers often use young cheddar, Colby, or other mild cheeses as a base. Utilizing cheese offcuts or those with cosmetic imperfections also helps to reduce food waste in the production process. This cheese is shredded or ground before being melted and blended with other ingredients.
The Crucial Role of Emulsifying Salts
One of the most important components distinguishing processed cheese is the use of emulsifying salts, which act as calcium-chelating agents. In natural cheese, a network of calcium holds the casein proteins together, which can cause the cheese to separate into a greasy oil and lumpy protein mess when heated. Emulsifying salts, such as sodium phosphate, potassium phosphate, and sodium citrate, disrupt this calcium network. This allows the casein proteins to unfold and mix evenly with the milk fat, creating a smooth, stable emulsion that melts uniformly without breaking.
Dairy and Fat Additives
Beyond the primary cheese content, several other dairy-based ingredients are frequently added to adjust the final product's texture, flavor, and fat content.
- Whey and Milk Solids: Adding milk solids, including skim milk and whey, increases the protein content and helps to achieve the desired texture and viscosity.
- Cream or Milkfat: Additional cream or anhydrous milkfat can be incorporated to enrich the flavor and mouthfeel, as well as to standardize the fat content.
- Water: Water is a key ingredient, especially in softer processed cheese spreads, and helps create the smooth, creamy texture.
Preservatives and Flavorings
To extend the product's shelf life and ensure a consistent flavor profile, manufacturers incorporate preservatives and flavorings.
- Preservatives: Mold inhibitors like potassium sorbate are often added to prevent spoilage and extend shelf stability. For some products, especially spreads, nisin may also be used.
- Flavorings and Colors: Artificial colors, such as annatto, provide a consistent yellow or orange hue. Other flavorings can also be added to enhance the taste, especially in products where a significant portion of the cheese has been replaced with other ingredients.
The Production Process: From Block to Slice
Making processed cheese involves a precise, multi-step process that ensures a consistent product every time.
- Preparation: Natural cheeses of varying age and type are chopped or ground into small pieces.
- Mixing and Melting: The ground cheese is melted in a large, heated mixer. Water, emulsifying salts, and other ingredients like milk proteins and flavorings are added and blended together. This step is critical for activating the emulsifying salts and creating a smooth, homogenous mixture.
- Pasteurization: The mixture is heated to high temperatures (typically over 160°F) for a specific duration to pasteurize the product, which kills bacteria and contributes to its long shelf life.
- Forming and Cooling: The hot, blended cheese is then transferred to packaging. The form of the final product—whether slices, blocks, or spreads—determines the cooling process. For slices and blocks, controlled cooling helps set the desired texture, while spreads are cooled rapidly.
Comparison: Processed vs. Natural Cheese
Understanding the ingredient differences makes it easy to compare processed and natural cheese.
| Feature | Processed Cheese | Natural Cheese |
|---|---|---|
| Key Ingredients | Natural cheese, emulsifying salts, water, milk solids, preservatives, flavorings, sometimes vegetable oil | Milk, salt, starter culture, rennet |
| Melt Properties | Melts smoothly and consistently without separating due to emulsifying salts | Can separate into oil and protein clumps when overheated, depending on the type and age |
| Shelf Life | Significantly longer shelf life due to pasteurization and preservatives | Much shorter shelf life; varies by moisture content |
| Texture | Soft, smooth, and consistent due to added ingredients and uniform manufacturing | Varies greatly, from soft and creamy (e.g., brie) to hard and grainy (e.g., parmesan) |
| Flavor Profile | Milder and more uniform flavor designed for consistency | Complex and diverse, developing with age and specific cheesemaking process |
Conclusion: The Chemistry Behind the Consistency
Ultimately, what is inside processed cheese is a thoughtful combination of natural dairy components and food additives that are engineered to deliver a specific, desirable outcome. The key lies in the emulsifying salts, which allow manufacturers to control the product's texture and meltability, ensuring a predictable and uniform result every time. This process is what differentiates it from natural cheese, creating a product with a longer shelf life and distinct performance properties that have made it a staple in many kitchens and food service operations. While not a replacement for traditional cheese, processed cheese serves its purpose perfectly in applications where a smooth, stable melt is required.
Learn more about the science of melting cheese and its different properties from Serious Eats.
