- With Mayo Clinic nutritionist
Katherine Zeratsky, R.D., L.D.
read biographyclose windowBiography of
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.
Nutrition basics (31)
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- Diet soda: Is it bad for you?
- Stevia: Can it help with weight control?
- see all in Nutrition basics
Healthy diets (10)
- Canola oil: Does it contain toxins?
- Butter vs. margarine: Which is better for my heart?
- Detox diets: Do they work?
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Healthy cooking (7)
- Moldy cheese: Is it OK to eat?
- Food poisoning: How long can you safely keep leftovers?
- When the heat is on, which oil should you use?
- see all in Healthy cooking
Healthy menus and shopping strategies (8)
- Calories in sushi: What are the low-cal options?
- Sodium nitrate in meat: Heart disease risk factor?
- What is BPA? Should I be worried about it?
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Nutritional supplements (18)
- What is wheatgrass — And why is it in my drink?
- Do the benefits of vitamin C include improved mood?
- Prenatal vitamins: OK for women who aren't pregnant?
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Question
Moldy cheese: Is it OK to eat?
If a piece of cheese has mold growing on it, should I throw the cheese away?
Answer
from Katherine Zeratsky, R.D., L.D.
Soft cheeses, such as cottage cheese, cream cheese and ricotta cheese, that have mold should be discarded. The same goes for any kind of cheese that's shredded, crumbled or sliced.
With these cheeses, the mold can send threads throughout the cheese. In addition, harmful bacteria, such as listeria, brucella, salmonella and E. coli, can grow along with the mold.
Mold generally can't penetrate far into hard and semisoft cheeses, such as cheddar, colby, Parmesan and Swiss. So you can cut away the moldy part and eat the rest of the cheese. Cut off at least 1 inch (2.5 centimeters) around and below the moldy spot. Be sure to keep the knife out of the mold so it doesn't contaminate other parts of the cheese.
Of course, not all molds pose a risk. In fact, some types of mold are used to make cheeses, such as Brie and Camembert. These molds are safe to eat.
If you're not sure what type of cheese you have or what to do if it grows mold, the safe course is to discard it.
Next questionFood poisoning: How long can you safely keep leftovers?
- Food safety: Foodborne illness. U.S. Department of Agriculture. http://www.fsis.usda.gov/Help/FAQs_Hotline_Illness/index.asp. Accessed June 30, 2012.
- Molds on food: Are they dangerous? U.S. Department of Agriculture. http://www.fsis.usda.gov/Fact_Sheets/Molds_On_Food/index.asp. Accessed June 30, 2012.
- 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 June 30, 2012.
- Zeratsky KA (expert opinion). Mayo Clinic, Rochester, Minn. June 30, 2012.
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