Blueberries can be used as natural edible dyes. According to the American Health Foundation, early American residents cooked milk and blueberries together to make gray pigments.
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Do not wash blueberries when storing them. A study by the University of Texas found that cleaning can accelerate the ripening process of blueberries and make them more likely to go bad. Blueberries with a layer of frost on the surface are the best. It is found that the frost on the surface of blueberry is naturally formed blueberry fruit powder, and the better the quality of blueberry, the more fruit powder. Blueberry fruit powder is nutritious and does not need to be washed off.
Many processed foods with blueberry flavor do not contain any blueberries. A survey published by the Consumer Health Center of Los Angeles Times found that some brands of cereals, breads and muffins use sugar, corn syrup, starch, cooking oil and artificial flavors and pigments to make fake blueberries.
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