Two weeks ago, among my finest friends and ex-cheese comrades, Chelsea, brought our old mentor/boss-lady, the illustrious Kim Martin, right into the shop. Neither of them had visited united state before, and it to be pretty amazing to show them about our tiny corner of the co-op.

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As lock were acquiring ready to leave, Chelsea pulled me aside and also silently pointed at a quarter-wheel of age Gouda on display screen in the earlier of the case, tapping the next of that to show me that it was every white.

“It’s not mold,” ns announced without skipping a beat. “It’s calcium lactate.”

This is something i actually have to write top top the range label when we wrap wedges that the cheese for sale, since people are inherently put off by a sheet of white on an otherwise butterscotch-orange cheese.

After all, most world are familiar with white, wispy molds cultivation on the exterior of cheese—either together the well-manicured coif that a bloomy-rind cheese or as errant growths on the cut confront of half-eaten cheese hunks life in the refrigerator cheese drawer.

But over there are various other white things that can flourish on your cheese, and also they room actually desirable: crystals!

You understand what ns referring to if you have bitten right into an aged Gouda, Cheddar, or Parmesan and felt that satisfying crunch. You likewise know the if you’ve sunk your teeth with the sticky orange exterior the a washed-rind cheese and felt a slight grittiness.

People frequently come into the shop trying to find cheeses that have actually “salt crystals” in them. Together you will discover below, there room two “families” that crystals that type in cheese. Only among those families has noþeles to perform with salt—and those room not generally the ones people go hunting for in a cheese shop. While a cheese could taste salty and have crystals in it, the doesn’t median the crunchy bits space salt, every se.

The crystals that people really want as soon as they are asking because that “salt crystals” are frequently referred come in the market as “flavor crystals.” That’s since the vision of this crystals is a authorize that you’ve discovered a flavorful, or fully-developed, cheese.

In fact, cheese crystals nothing have any effect on the method a cheese tastes—they room flavorless and scentless. But they do impact other sensory perceptions of a bite of cheese: sound (crunching), touch (bumpiness or stormy texture), and sight (white spots, clusters, or patches).

There are several different types of crystals that prosper in or ~ above cheese at various times in the cheese-making or -aging process. They room either going to it is in the product that mineral (salt) emulsion during cheesemaking or protein break down (proteolysis) as the cheese ages.


The crystals you may not an alert as lot are the “inorganic crystals,” or crystals developed by minerals. This “family” of crystals is produced when salt emulsify, or disperse throughout the cheese there is no dissolving, during the cheese-making process. (These are the ones you could call salt crystals.)

For example, calcium phosphate crystals space most commonly found under the rinds that bloomy-rind cheeses, help them come to be soft together they ripen. Two other kinds of inorganic crystals, Ikaite and also Struvite, space what you notice when a washed-rind cheese has a gritty rind; Ikaite crystals are formed from calcium carbonate, vice versa, Struvite crystals come native magnesium ammonium phosphate.

The crystals the are most noticeable in cheese space the “organic crystals” that are formed by the malfunction of amino acids throughout the cheese-aging process.

As a cheese ages, it loser moisture and its protein structure contracts and also stretches. Together this happens, the amino acid chains running with the cheese that consist of that protein structure start to break up; the whole process of protein malfunction is referred to as proteolysis.

Each kind of organic decision that friend will discover in a cheese is named after the amino-acid chain that broke up to produce it.

For example, tyrosine crystals provide aged goudas their famed crunchy texture. They can thrive inside the paste of cheese, or all approximately the tiny holes inside a cheese.

Leucine crystals have actually a similar effect, but have a more diffused, smear-like appearance 보다 tyrosine crystals. Both that these types of crystals may be uncovered in goudas, Alpine-style (Swiss) cheeses, and also Grana-style cheese (e.g., Parmigiano Reggiano, Grana Padano, Piave, etc.).

And climate there is calcium lactate, which generally forms on the external of rindless cheddars together they age. Calcium lactate formations are seen as a sign that the cheese has actually aged because that a lengthy time and also should have actually a more developed odor profile.

Calcium lactate originates from an earlier stage that proteolysis, once lactose is still current in the fluid milk that will certainly be fermented into cheese. Together the bacterial culture in the cheese eats up every one of the lactose, or milk sugar, in the milk, the bacteria develop lactic acid. Calcium lactate is a byproduct of that lactic acid communicating with calcium carbonate in the cheese end time.

Just in situation you to be wondering what calcium lactate needs to do with amino acids, lactic mountain bacteria convert the protein in cheese into peptides, and also then right into amino mountain (like tyrosine and also leucine).

You can uncover several varieties of crystals top top the exact same cheese—tyrosine and leucine crystal deposits on aged Parmigiano Reggiano, for example.

So exactly how you do recognize which is which?

Generally speaking, calcium lactate will certainly be found on the exterior of a cheese (usually a cheddar), and also tyrosine or leucine crystals will be on the inside. Calcium lactate have the right to also type on the inside of cheese, yet tyrosine and also leucine crystals cannot.

Tyrosine crystals will certainly be hard and crunchy, conversely, calcium lactate will certainly be slightly softer, and also sometimes nearly powdery or flaky, in comparison to tyrosine or leucine crystals.

Calcium phosphate, Ikaite, and also Struvite crystals will certainly be discovered on any “mold-ripened” cheese: friend may an alert them in the slight grittiness at the rind the a bloomy rind cheese, prefer Brie or Camembert, or a washed-rind cheese, favor Epoisses, Chimay, or Grayson. (Washed-rind cheeses, also called “smear-ripened cheeses,” fall into the mold-ripened category because their rinds are produced by a complex ecosystem of molds and yeasts.)

What all of these crystals have in common—other 보다 the structure they create, of course—is the they signify age in a offered cheese. They assist mold-ripened cheeses come to be soft, and they allow you know when a tough cheese has actually been unique aged.

So if girlfriend peel open a chunk that Cheddar and find white store marbling that is outsides, rejoice! You’ve gotten a well-aged cheese that is bound to taste delicious.

And if you crack open a wedge of Gouda, Gruyere, or Parmigiano Reggiano and also see little white spots either riddling the dough or clustered about the cheese’s eye holes, likewise rejoice! You’ve obtained tyrosine or leucine crystals, and that cheese’s structure is going to be prefer cheese candy.

(Cheese candy, good readers! could you wish because that anything better?)

The moral of the story? If you watch white on her cheese, don’t simply throw the away. Touch the white ingredient to check out if it’s hard or soft. If that soft, it’s probably mold (and you deserve to just reduced it off of a firm cheese). If it’s hard, that a precious tiny colony that crystals, and also you have hit the cheese jackpot.


Tansman, Gil Fils. “Crystal.” The Oxford Companion to Cheese. Ed. Catherine Donnelly. Brand-new York: Oxford university Press, 2016. 205-6.

Polowsky, Pat. “The Wonderful human being of Cheese Crystals.” Cheese science Toolkit. Https:// Accessed 4 Nov. 2018.

Tansman, 205-6.

Polowsky, “The Wonderful civilization of Cheese Crystals.”

Polowsky, Pat. “Lactose and Lactic Acid.” Cheese science Toolkit. Accessed 4 Nov. 2018.

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Johnson, Mark. “Crystallization in Cheese.” Dairy Pipeline, vol. 26, no. 3, 2014. Wisconsin facility for dairy Research. Https:// Accessed 4 Nov. 2018.