White spots on Parmesan cheese - What does it mean?

When you see a white speck on your food, it’s natural to assume that mold has ruined your food.

If you had some Parmesan waiting in the fridge for the perfect recipe, don’t immediately panic if you unwrap it to find it speckled with white.

What are white spots on parmesan cheese?

The white spots on Parmesan cheese can be mold, but they can also be tyrosine or calcium lactate crystals that develop the flavor and fragrance of certain aged cheeses. If they are inside the cheese, they are probably crystals. If they’re just outside and the cheese doesn’t taste good, it may be mold.

Understanding the difference between mold and crystals can save your day, or at least your dinner.

In this article, you’ll learn what cheese crystals are, how to distinguish them from white mold, and when and how to save Parmesan instead of throwing it away.

Parmesan vs. Parmigiano Reggiano

If there are white flecks in your Parmesan, the first thing to find out is whether you have imitation Parmesan, which is the most common type of Parmesan in North America, or whether you have real Parmigiano Reggiano.

Parmesan is actually the imitation version of Parmigiano Reggiano. Authentic Parmigiano Reggiano must follow strict rules, regulations and guidelines to deserve the title.

Here are some of the qualifying factors:

1. Must be made in Italy
2. It can only contain 3 ingredients: milk, salt and animal rennet.
3. Must mature at least 12 months
4. Must be approved by the regulatory council

If your Parmesan comes in a shelf-stable container, it’s an imitation.

But even if it comes in a triangular block of hard and white cheese from the deli section of your grocery store, there’s an above-average chance that it’s still “Parmesan,” and not true Parmigiano Reggiano.

The flavors of real vs. imitation Parmesan are significantly different when tried side by side, but due to the difference in price and the saturated market for imitation Parmesan, many people have never even tried the official cheese.

The reason it’s so important to know if you have the real Italian hard cheese or an imitation variety is that white spots can mean completely different things, depending on which one you have.

One way to tell is to try melting your Parmesan , or a little bit of it. If it melts easily, it’s Parmigiano Reggiano. If it has a hard time melting and separates, burns, or becomes stringy, it’s probably imitation Parmesan.

parmesan cheese mold

If you have the more common imitation Parmesan, the white spots on your cheese are more likely to be mold than something fabulous, as we’ll see later.

Many of the cheeses that America calls “Parmesan” contain additives, preservatives, flavorings, and a variety of other ingredients, or even cheeses.

These can lengthen the shelf life of your cheese or shorten it, compared to authentic Parmigiano Reggiano.

Mold in grated Parmesan cheese

You may never have considered Parmesan cheese going bad , as it is a hard cheese and has a long shelf life, but just like any other dairy product, it has its limits.

Grated Parmesan cheese, whether real or imitation, is more likely to mold than a block of cheese. This is simply due to the surface being exposed to air and moisture, and therefore to bacteria.

When cheese molds, it is likely to turn blue, although it can present as white mold with no blue at all. White mold is very hard to see on pre-shredded cheese, so you’re more likely to accidentally taste it than see it.

Any blue stain is a sure sign of mold.

It’s also helpful to keep in mind that if your cheese does happen to get a little moldy, it’s much easier to cut the affected area out of a block of hard cheese than it is to remove all the bits inside the grated cheese.

Investing in a grater and a block of hard Parmigiano Reggiano will not only please your palate, but can actually pay off in the long run by reducing waste if you don’t use it very often.

cheese crystals

Not all foods that develop white spots go bad. In fact, they can be a good sign for your culinary pursuits. For example, sweet potatoes may have oozing or white spots if they are especially sweet.

Although you may be predisposed to assume that any white spot on the cheese is mold, authentic, aged Parmigiano Reggiano can develop crystals, rather than mold, and this would actually be a very good thing.

As certain types of cheese age, the proteins break down in a way that creates inconsistencies in texture and flavor. The texture can be a bit crunchy, and the flavor can be especially sweet or salty.

There are two types of cheese crystals that can form in aged cheese, but will not form in imitation Parmesan: tyrosine and/or calcium lactate crystals.

Tyrosine crystals in cheese

Tyrosine is an amino acid that forms a crystal by accumulating during the aging process of certain cheeses.

This type of shiny white crystal forms on the inside of the main block of the cheese, but can also be seen on the outside. They usually form where there are small eyes or tiny air pockets. They are very firm and crunchy.

They add more texture than flavor, but they tend to garnish the most flavorful cheeses, which is why they are often called flavor or salt crystals.

Calcium lactate in cheese

This type of crystal can be found inside the cheese or on the surface. It is a softer, paler crystal, which mixes a little better with the cheese itself.

Calcium lactate crystals form when the lactose in cheese breaks down during the aging process. Lactic acids are formed, which bind to calcium ions to form calcium lactate.

Calcium lactate crystals are most likely to form where the cheese has been exposed to moisture, usually on the surface of the cheese. It looks more like a white powdery patch than well-defined white patches.

Calcium lactate crystals by themselves do not change the flavor of the cheese, but are often a sign of a well-cured Parmesan block that will have a robust flavor profile.

Cheese crystals or mold?

How can you tell if the white spots on your cheese are crystals or mold? The first clue is in the quality of the cheese.

A true Parmigiano-Reggiano is very likely to have crystals and very unlikely to develop mold, because it is a very low moisture cheese.

The next clue is whether the stains are on the inside of the cheese or on the outer layer. If they are inside the cheese, they are almost certainly crystals. This will add a nice burst of flavor to your already delicious Parmesan.

If you’re still not sure, try a little. Even though it’s on the outside of the cheese, it may not be mold.

A small amount of mold isn’t likely to harm you, unless you have an allergic reaction to it, but it will give your taste buds a chance to tell you whether the growth is a good or bad addition to your cheese.

White mold on cheese

If you’re convinced that the white spots on your cheese are indeed mold, your next questions are most likely: “Is white mold on cheese dangerous? Should I throw it away or try to salvage what I can?” .

First of all, is your parmesan cheese block or grated? If it is grated, you should discard the entire container or package.

Unfortunately, it is nearly impossible to remove white mold contamination from a collection of shredded cheese pieces, especially when the cheese itself is almost the same color as the mold.

Mold on cheese can support the growth of potentially dangerous bacteria, such as E. coli and salmonella, so it’s best not to risk it.

However, if you have a very hard Parmesan block that has mold on the surface, you can cut around the mold and save the rest of the cheese.

Hard cheese has very little moisture, so mold is likely due to exposure to outside moisture and cannot penetrate far into the cheese.

Cut at least a 1-inch radius around any mold and save the rest, wrapping carefully to prevent more moisture from attacking your cheese.

Related questions

How long is Parmesan aged?

Most commercial Parmesan cheese is not true Parmesan and does not have a specific ripening period, if any.

However, true Parmigiano Reggiano must be aged a minimum of 12 months to pass inspection and gain approval.

Aging beyond 1 year is at the discretion of the producer and can be carefully aged to develop aroma, texture and flavor over several years.

Cheeses of different ages will be more suitable for different dishes. A younger cheese is more dairy, with brighter, almost fruity flavors. Older cheeses become more crumbly and develop a stronger umami flavor.

Is Parmesan vegetarian?

Many, but not all, vegetarians consume cheese and cheese-based products on a regular basis, but Parmesan shouldn’t be one of the varieties included.

This is because Parmesan is not strictly made with milk, but also uses animal rennet to curdle the cheese as it is made.

Animal rennet is an enzyme found in the stomach lining of calves that helps them digest lactose. This same enzyme causes the milk used to make cheese to coagulate, separating the curds from the whey.

Not all cheeses are made with rennet, but Parmesan is, unless specifically stated otherwise. However, you can find cheeses made with vegetable rennet.

Is the Parmesan rind edible?

Parmesan, specifically Parmigiano Reggiano, develops a hard rind as it ages, which protects the fresh cheese underneath.

It’s technically edible, but few people care to munch on the tough, chewy rind, despite the strong Parmesan flavor.

The best way to use your Parmesan rind is to cook with it. They can be boiled to flavor a sauce, stock, or even slow-cooked grains or pasta.

You just have to make sure to remove what is left of the crust before serving. You can also dip a strip of rind in olive oil to create Parmesan-infused oil.