- With Mayo Clinic nutritionist
Katherine Zeratsky, R.D., L.D.
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Katherine Zeratsky, R.D., L.D.
Katherine Zeratsky, R.D., L.D.
As a specialty editor for the nutrition and healthy eating guide, Katherine Zeratsky helps you sort through the facts and figures, the fads and the hype to learn more about nutrition and diet.
A Marinette, Wis., native, Katherine is certified in dietetics by the state of Minnesota and the American Dietetic Association. She has been with Mayo Clinic since 1999.
She is active in nutrition-related curriculum and course development in wellness nutrition at Mayo Clinic in Rochester, Minn., and nutrition education related to weight management and practical applications of nutrition-related lifestyle changes.
Other areas of interest include food and nutrition for all life stages, active lifestyles and the culinary arts.
She graduated from the University of Wisconsin-Madison, served a dietetic internship at the University of Iowa Hospitals and Clinics, and worked as a registered dietitian and health risk counselor at ThedaCare of Appleton, Wis., before joining the Mayo Clinic staff.
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Healthy menus and shopping strategies (7)
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Question
Moldy cheese: Is it unsafe to eat?
If a piece of cheese has mold on it, should I throw the cheese away?
Answer
from Katherine Zeratsky, R.D., L.D.
The answer depends on the type of cheese. Soft cheeses, such as cottage cheese and cream cheese, that grow mold should be discarded. With these cheeses, the mold can send root threads throughout the cheese. In addition, harmful bacteria, such as listeria, brucella, salmonella and E. coli, can grow along with the mold. The same goes for any kind of cheese that's shredded, crumbled or sliced.
Mold generally can't penetrate far into hard and semisoft cheeses, such as Cheddar, Colby and Swiss. So you can cut away the moldy part and eat the rest of the cheese. Cut off at least one inch around and below the moldy spot. Be sure to keep the knife out of the mold itself so that it doesn't contaminate other parts of the cheese.
Of course, not all molds pose a risk. In fact, some types of mold are even used to make cheeses, such as Brie and Camembert. These molds are safe to eat. But mold that's not part of the manufacturing process is a problem. For advice about handling specific types of cheese, consult the chart. If you're not sure what type of cheese you have or what to do if it grows mold, the safe thing to do is discard it.
| Mold on cheese: When to use and when to discard | ||
|---|---|---|
| Type of cheese | Discard — do not eat | OK to eat after mold is removed |
| Any cheese that is shredded, crumbled or sliced | X | |
| Asiago | X | |
| Blue cheese | X | |
| Brie | X | |
| Camembert | X | |
| Cheddar | X | |
| Colby | X | |
| Cottage cheese | X | |
| Cream cheese | X | |
| Gorgonzola | X | |
| Gruyere | X | |
| Neufchatel | X | |
| Parmesan | X | |
| Ricotta | X | |
| Romano | X | |
| Stilton | X | |
| Swiss | X | |
Thanksgiving turkey: Can you cook it frozen?
- Food safety: Foodborne illness. U.S. Department of Agriculture. http://www.fsis.usda.gov/Help/FAQs_Hotline_Illness/index.asp. Accessed Dec. 7, 2010.
- Molds on food: Are they dangerous? U.S. Department of Agriculture. http://www.fsis.usda.gov/Fact_Sheets/Molds_On_Food/index.asp. Accessed Dec. 7, 2010.
- Retail food safety program information manual on date marking of cheese. U.S. Food and Drug Administration. http://www.fda.gov/Food/FoodSafety/RetailFoodProtection/IndustryandRegulatoryAssistanceandTrainingResources/ucm113942.htm. Accessed Dec. 7, 2010.
- Zeratsky K (expert opinion). Mayo Clinic, Rochester, Minn. Dec. 15, 2010.
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