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Feature Articles: Food, Fitness and Cooking and Produce


Sooty Blotch in Apples Not a Health Concern

Janet Hackert, CPD, Nutrition and Health Education Specialist in Harrison County, University of Missouri Extension

This year the apple harvest has been bountiful! But some of those beautiful apples show blemishes caused by sooty blotch. Although they may not look nice, these apples “do not pose a health risk,” says Dr Michael Ellis from the Department of Plant Pathology at Ohio State University.

An apple with sooty blotch has brown-to-dull black spots. The spots do not have clear-cut edges, but rather have an indefinite outline. The spots may be confined to one small area or may cover most of the fruit’s surface. Most commonly this problem occurs with Golden Delicious or Grimes apples, but may show up on any variety.

Sooty blotch is caused by a fungal infection. It is particularly prevalent later in a season when May and June were cool and wet and July and August were hot and dry – much like we have had in many parts of northwest Missouri this year.

The good news is that sooty blotch is only ‘skin deep.’ Because it is confined to the surface of the fruit, it is easy to remove it. As Dr. Ellis reports, “Removal of the fungus by washing, rubbing or peeling the fruit results in fruit that is acceptable for cooking or eating fresh.” Whether the process is to remove sooty blotch or any number of potentially dangerous microorganisms, washing and rubbing any type of fruit is recommended to keep that food safe to eat.

Keep apples at 35-40 degrees Fahrenheit for optimal long-term storage. Apples at this temperature last far longer than apples kept at room temperature. Temperatures in a garage or basement may be cool and will prolong the shelf life of apples. Even better would be to use a spare refrigerator where apples would be kept at a constant temperature. For apples with sooty blotch, the same storage conditions are recommended. Even after being held in cold storage, “sooty blotch could increase, but not be a health risk,” says Dr. Ellis.




Last update: Tuesday, May 05, 2009




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