That white stuff on your cheese might not be mold! It could be calcium lactate crystals, a harmless byproduct of aging. These crystals, often found on aged cheeses like cheddar, Gouda, and Parmesan, form when lactic acid reacts with calcium in the cheese. They usually appear as small, white, gritty or crunchy spots and indicate a well-aged and flavorful cheese. While they might look unusual, calcium lactate crystals are safe to eat and contribute to the cheese's unique texture and taste. So, before you toss that block of cheese, consider that the "white stuff" might actually be a sign of quality.
In a 2018 article titled "There's White Stuff Growing on Your Cheese That Isn't Mold," The Philadelphia Cheesesteak Company's blog elucidates the nature of the sometimes alarming, yet frequently harmless, white crystalline formations that can appear on the surface of various cheeses. The article meticulously explains that these formations are not, in fact, mold, but rather crystalline structures composed of calcium lactate. This compound arises from a fascinating interplay of chemical processes within the cheese during the aging process. Lactic acid, a natural byproduct of the bacterial cultures responsible for cheesemaking, reacts with calcium present in the cheese. This reaction results in the formation of calcium lactate, which, due to its lower solubility, precipitates out of the cheese's internal moisture, eventually appearing as small, white, often crunchy crystals on the cheese's surface.
The article further elaborates on the specific conditions that favor the formation of these calcium lactate crystals. Higher moisture content within the cheese provides a more conducive environment for the reaction between lactic acid and calcium, increasing the likelihood of crystal formation. Additionally, the article notes that aged cheeses, particularly harder varieties, are more prone to exhibiting these crystals due to the longer timeframe for these chemical reactions to occur and the denser texture which can concentrate the crystals on the surface.
The article emphasizes the benign nature of calcium lactate crystals, assuring readers that they are perfectly safe to consume and do not indicate spoilage. Indeed, these crystals often contribute a pleasant textural complexity to the cheese, sometimes described as a slight crunch. While visually they might be mistaken for mold, the article provides clear distinctions: mold tends to appear fuzzy, exhibit a variety of colors beyond white, and often imparts an unpleasant odor. Calcium lactate crystals, in contrast, maintain a distinctly crystalline structure, remain consistently white, and are odorless.
Finally, the article offers practical advice for handling cheese exhibiting these crystals. While perfectly safe to eat, the article acknowledges that some might find the texture undesirable. It suggests gently scraping the crystals off the cheese's surface if preferred. The article concludes by reassuring consumers that the presence of calcium lactate crystals is a natural phenomenon in cheesemaking, often indicative of a well-aged and flavorful product.
Summary of Comments ( 17 )
https://news.ycombinator.com/item?id=43535688
Hacker News users discuss the various types of "white stuff" that can appear on cheese, beyond just mold. Several commenters point out that the article fails to mention tyrosine crystals, which are common on aged cheeses and contribute to their flavor. Calcium lactate is also mentioned as another common, harmless crystalline formation. Some users express concern about the author's seeming encouragement to just scrape off the mold and eat the cheese, with several arguing that this is unsafe for certain molds that penetrate deeply. Others note the article conflates "safe" with "harmless", pointing out that even harmless molds might not be palatable. Finally, a few comments offer additional resources for identifying cheese molds and determining their safety.
The Hacker News post linking to the article "There's White Stuff Growing on Your Cheese That Isn't Mold" has generated a moderate number of comments, primarily discussing the nature of cheese crystals, their edibility, and different types of cheese.
Several commenters delve into the science behind these crystals, identifying them as calcium lactate or tyrosine. They explain that calcium lactate crystals are common in aged cheeses like Cheddar and Parmesan, and are formed when lactic acid reacts with calcium. These crystals are generally considered harmless and even contribute to the texture and flavor of the cheese. Tyrosine crystals, on the other hand, appear as small, white, needle-like structures and are often found in harder cheeses. They're also generally harmless and indicate a well-aged cheese.
A significant portion of the discussion revolves around the edibility and palatability of these crystals. Many commenters state that they are perfectly safe to consume and often contribute a pleasant crunch. Some even suggest that the presence of these crystals is a sign of a good quality, aged cheese. However, some express personal preferences, with a few finding the texture unpleasant.
The types of cheese prone to crystal formation are also a topic of discussion. Cheddar, Parmesan, and aged Gouda are frequently mentioned as examples. One commenter even shares a personal anecdote about encountering these crystals in an aged Comte cheese.
While the overall tone is informative and amicable, a minor debate arises about the accuracy of the article's title. Some argue that while technically these crystals aren't mold, the phrasing might be misleading to the average reader. They suggest a more precise title would focus on the harmless nature of the crystals rather than their distinction from mold.
Finally, some comments veer slightly off-topic, discussing other aspects of cheese aging and storage, including the use of cheese paper and the ideal humidity for preserving cheese.