If you're looking to cut back on the amount of fat in your diet, you may have come across fat-free cheese. But what is fat-free cheese, what does it taste like, and how is it made?
How is Cheese Made?
Cheese is made by combining milk (usually cow's milk) with a starter culture of bacteria that digest the milk sugar, called lactose, and produce lactic acid. It's this starter culture that helps determine the ultimate flavor of the cheese. Next, an enzyme called rennet is added which causes the milk to curdle, producing solid lumps called curds, leaving behind a protein-rich liquid called whey.
The whey is drained away and the remaining curds are cooked, cut up and pressed together, squeezing out still more whey, and aged for several weeks, up to 12 months or even longer. Salt and other flavorings are added, and the resulting product is cheese.
These days, the fat content of the cheese is controlled by manipulating the fat content of the milk that's used to make it. Each cheese has its own particular fat content. In general, higher-fat cheeses are creamier, such as mascarpone, and lower fat cheeses are harder, such as Parmesan.
Fat-free cheese is cheese that is made using fat-free milk. But how is fat-free milk made?
How is Fat-Free Cheese Made?
Milk is an emulsion of fat, protein and water. When milk comes out of the cow, its fat globules are large, and since they're lighter than the water, they separate and float to the top in the form of cream. In the old days, that's how a bottle of milk came. You could either shake it up to combine the cream with the milk, or just enjoy the cream from the top of the bottle.
These days, though, milk is homogenized, by forcing it through a fine-mesh filter, which breaks up the fat globules into smaller globules, so that they are distributed evenly instead of floating to the top.
Those fat globules can be removed altogether, using a centrifuge. This device spins the milk at high speed, causing the fat globules to separate entirely, leaving skim, or fat-free milk in one container, and all the fat in another. The fat can then be added back into the skim milk in the precise proportions necessary for making the various kinds of milk, including whole milk (3.5 percent fat), 2 percent, 1 percent or skim milk (0 percent fat).
To make fat-free cheese, then, it's simply a matter of removing the fat from the milk and then using the fat-free milk to make the cheese.
What Does It Taste Like?
Fat-free cheeses will vary in flavor according to what type of cheese it is. For instance, fat-free ricotta is already a thing, as is fat-free mozzarella. But fat-free cheddar and Monterey jack will take some getting used to, in part because of their flavor (much of a food's flavor comes from its fat), but also their mouthfeel. Fat-free cheeses are typically much more crumbly and harder; they're not altogether creamy.
It is worth noting that some manufacturers make up for the lack of flavor in fat-free cheese by adding additional salt. So it's possible that you might find fat-free cheese to be a bit saltier than what you're used to. This also has implications for those who are trying to manage their sodium intake (see below).
Using Fat-Free Cheese
Probably the biggest issue with fat-free cheese is that it doesn't melt as well as full-fat or reduced-fat cheeses. You can work around this by using it in its shredded form, which will help to some extent. But fat-free cheese will never melt all the way, at least not in the way that you're used to. You certainly won't be able to make a grilled cheese with it.
For example, if you bake a casserole using fat-free cheese, mix some cheese inside the casserole and then sprinkle some on top, you can expect that the cheese inside will melt somewhat, while the cheese on top will not. It seems to be a function of surrounding moisture and perhaps the surrounding fats of other ingredients that help fat-free cheese to melt. The cheese on top will brown somewhat, but not quite melt.
Whether this is acceptable to you or not is a personal decision. If you're looking to reduce the amount of fat in your diet, this might be a worthwhile trade-off, or it might not.