Slices, string cheese and cream cheese: the supermarket aisle explained

Wrapped slices are usually processed cheese

Individually wrapped slices are generally cheese that has been melted with emulsifying salts and set again, which is why they melt evenly and never split. That is engineering, not a defect. The cost is sodium: processed cheese runs around 1,200 milligrams per 100 grams, among the highest of any cheese. The category line on the back tells you which you have. Where the category begins is set nationally: the US grades it by cheese content, requiring process cheese food to be at least 51 per cent cheese, while Korea counts anything fully melted and re-formed.

The cheese most slices are built on:

How processed cheese came to exist

In 1911, two men in Thun, Switzerland were trying to make a cheese that would keep. They added sodium citrate to melted emmental, found that it emulsified smoothly and set firm again on cooling, and called the result boxed cheese. A few years later an American businessman named Kraft patented a comparable process, and that became the wrapped slice we know. So this cheese was invented for distribution from the very beginning. Judged against its original purpose, it is a complete success.

The cheese that experiment started from:

Why string cheese pulls apart in strands

Mozzarella-family cheeses are made by stretching the curd in hot water. String cheese is stretched in one direction only, so the protein fibres set in parallel alignment — hence the strands. A ball of fresh mozzarella, stretched without that directional working, does not pull apart the same way. The fun of tearing it is a consequence of manufacture, not an accident. The grain is also temperature-sensitive: it strands cleanly when cold and goes slack if left out at room temperature.

Made by the same stretching method:

Cream cheese is an unaged fresh cheese

Milk and cream set with lactic cultures and never ripened, which is why it is mild with a faint tang. It softens rather than flows under heat, so it suits baking and sauces. Sodium runs about 90 to 105 milligrams per 28 grams, lower than a slice. Once opened it behaves like any fresh cheese and spoils quickly, so write the date on it. Do not confuse it with mascarpone, which is cream set with acid — barely fermented and far richer. That difference is why a tiramisu made with cream cheese tastes sour.

The two most often mistaken for each other:

Pizza cheese is a blend

Bagged pizza shreds are usually mozzarella-led with other cheeses added for flavour alongside the stretch — the same reasoning a good pizzeria applies. But shredded cheese has far more surface area, so it dries and spoils faster than a block. It also tends to contain starch or cellulose to stop the strands clumping, which changes how it melts. In a baked dish the difference is small; in a sauce or a fondue, where smooth melting is the whole point, it shows. If you use it rarely, buy a block and grate as needed.

What is usually in the bag:

Things that taste of cheese but are not

If a frozen pizza tastes cheesy but somehow wrong, it may be imitation cheese — vegetable fat and protein engineered to mimic the texture. Cheap, admirably stretchy, and containing almost nothing from milk. Regulators set a floor — 51 per cent actual cheese for process cheese food in the US, 18 per cent cheese-derived milk solids in Korea — and below it the product is legally no longer a dairy food at all. Telling them apart is easy: read the category line on the back. The word cheese in large letters on the front proves nothing. This is not a judgement, only a case for knowing what you are buying.

Is it good value?

Wrapped slices are surprisingly expensive per gram, because individual wrapping costs money. The same spend on a block of gouda or cheddar buys considerably more cheese. Slices do save you the cutting and give you an exact portion, so it is not a clean comparison — but for a household that uses cheese daily, buying blocks and slicing as needed clearly wins. Warehouse-store blocks are the best value of all, and hard cheeses keep well enough that a large piece is no risk.

Buy these as a block and the price changes:

Getting the most from supermarket cheese

Each one has a job. Slices melt evenly, so they belong on toast and in burgers. String cheese is a snack. Cream cheese spreads and bakes. Bagged shreds are for oven dishes. Add one more item and the range widens considerably: a hard cheese for grating. It goes into pasta, soup, salad and fried rice a little at a time, adds savouriness, and can replace salt outright. It also keeps for months, so you rarely need to buy it.

The one extra that widens everything:

If you want to move up a step

The natural next purchase after wrapped slices is a block of semi-hard cheese. Mild, long-lived and useful everywhere, it is impossible to get wrong. Buy 200 grams of gouda or cheddar, slice it yourself, and the difference from a wrapped slice is immediately obvious. A bloomy rind comes after that. But do not take this the wrong way: supermarket cheese is not inferior, it is different equipment. What goes on instant noodles need not be what goes with wine. Even once you know good cheese, there will still be slices in the fridge — and there should be.

Laid out in the order to climb: