Block cheese like cheddar, Swiss, or gouda is not processed cheese, but it is technically a “processed food” in the broader sense. That distinction matters more than it might seem. Block cheese is made from just a few ingredients (milk, salt, bacterial cultures, and an enzyme called rennet), while processed cheese products like American cheese slices contain a blend of cheeses mixed with emulsifiers, colorings, and other additives. The two sit in very different categories when it comes to ingredients, nutrition, and food classification systems.
What “Processed” Actually Means for Cheese
The confusion comes from two different uses of the word “processed.” Almost every food you eat has been processed in some way. Washing lettuce is processing. Pasteurizing milk is processing. In that broad sense, yes, block cheese is processed: milk has been transformed into a solid food through fermentation, coagulation, and pressing.
But when most people ask “is block cheese processed,” they’re really asking whether it’s the same thing as those individually wrapped slices or cheese spreads. It’s not. The NOVA food classification system, widely used in nutrition research, draws a clear line. It places traditional cheeses like cheddar in Group 3 (processed foods), alongside bottled vegetables, canned fish, and freshly made bread. These are recognizable foods made by adding salt, oil, or sugar to whole ingredients. Processed cheese products like American cheese, on the other hand, land in Group 4: ultra-processed foods.
How Block Cheese Is Made
Traditional cheesemaking is a surprisingly simple process. It starts with milk, to which bacterial cultures and an enzyme called rennet are added. The bacteria convert the natural sugar in milk (lactose) into lactic acid, which begins to acidify and thicken the milk. Rennet causes the milk protein to form a mesh-like gel that traps water and fat.
Once the gel is firm enough, it’s cut into small pieces and cooked gently. The liquid whey is drained off, leaving behind the solid curds. Salt is added, and the curds are pressed into molds to form a dense block. For a cheese like cheddar, the block is then aged for weeks to months (or even years), which develops its flavor and texture. The entire ingredient list for a typical block of cheddar is milk, salt, bacterial cultures, and enzymes. That’s it.
How Processed Cheese Differs
Processed cheese starts where block cheese ends. Manufacturers take one or more natural cheeses, melt them down, and blend them with additional ingredients: water, emulsifying salts, artificial coloring, preservatives, and sometimes artificial flavors. The emulsifying salts (typically sodium phosphate or sodium citrate compounds) prevent the fat and protein from separating, giving processed cheese its uniform, meltable texture.
The FDA requires these products to be labeled with their full name: “pasteurized process cheese,” “pasteurized process cheese food,” or “pasteurized process cheese product,” depending on how much actual cheese they contain. All the words in that name must appear in the same size and style on the label. A block of cheddar, by contrast, is simply labeled “cheddar cheese.” If you’re unsure what you’re buying, the label tells you everything.
The Sodium Gap
One of the biggest nutritional differences between block cheese and processed cheese is sodium. A study analyzing retail cheeses across the United States found that cheddar cheese averaged 615 milligrams of sodium per 100 grams. Process cheese averaged 1,242 milligrams per 100 grams, roughly double. That’s a significant difference if you’re watching your salt intake, and it’s largely driven by the emulsifying salts and extra sodium added during manufacturing.
Block Cheese vs. Pre-Shredded Cheese
There’s one more distinction worth knowing. Block cheese and pre-shredded cheese from the same brand might seem identical, but they’re not quite. Shredded cheese is coated with anti-caking agents to keep the shreds from clumping in the bag. These are typically blends of potato starch, cellulose (a plant fiber), corn starch, or calcium sulfate, applied at 1 to 5% of the total weight. The cheese itself is the same, but those added powders are absent from block cheese. If you want the simplest ingredient list possible, buying a block and grating it yourself is the way to go.
How to Tell What You’re Buying
The fastest way to check is the ingredient list. Block cheese made the traditional way will have four or five ingredients: milk (or pasteurized milk), cheese cultures, salt, and enzymes. Some varieties add annatto for color, which is a natural plant-based dye. If you see emulsifiers, sodium phosphate, milk protein concentrate, whey, or the word “process” anywhere on the front label, you’re looking at a processed cheese product.
The packaging itself is also a clue. Cheese sold in blocks, wheels, or wedges with a short ingredient list is almost always natural cheese. Products sold as individually wrapped slices, squeezable tubes, or shelf-stable jars are typically processed. Price can hint at it too: processed cheese products tend to cost less per ounce because they stretch a smaller amount of real cheese with water and additives.