Have you seen mold on apples and other fruits in your refrigerator or cupboard? Then it’s time to throw them away. Like most fruits, apples can go bad and make you sick. An apple that is firm and shows no signs of mold or insect holes should be safe to eat. Cut it in half before eating and check the core for mold. What makes apples rot? These juicy fruits have a long shelf life and can last for weeks. Sometimes it can be hard to tell if an apple is rotten or just overripe but still edible. First, make sure you understand what causes apples to turn brown and rot. Many fruits, including apples, bananas, pears, plums, peaches and mangoes, produce ethylene as part of the ripening process. This gas directly impacts their texture, flavor, nutritional value and other characteristics, according to a study published in the April 2013 issue of the Journal of Experimental Botany. Ethylene is not the only factor responsible for fruit rot, however. Mold, oxidation, fungus, light, heat and humidity all play a role. For example, when you cut an apple, the chemicals in its flesh are exposed to oxygen in the air, which promotes the formation of polyphenol oxidase, an enzyme that causes the fruit to turn brown. This process is called oxidation. Dangers of Mold on Apples Microorganisms, such as fungi and mold, can also affect the shelf life of apples. Warm, humid storage conditions, for example, encourage the growth of mold. Some types of mold can grow in the refrigerator, so it’s important to clean your refrigerator regularly and store fresh or cut fruit covered with plastic wrap. The USDA warns that mold can cause respiratory problems and allergies. Some species produce harmful substances called mycotoxins. These compounds are often responsible for foodborne illnesses, alterations in immune function and even cancer, says the World Health Organization. There are more than 300 mycotoxins, each affecting different foods, according to a study published in June 2017 in the International Journal of Environmental Research and Public Health. Patulin, produced by the species Penicillium expansum, commonly affects apples and their juice as well as other fruits, such as pears and grapes. When ingested in large quantities, it can cause nausea, ulcers, bleeding and even cancer. Mold tends to grow on fruits and other highly acidic foods, according to the USDA. Typically, moldy fruits have velvety, coin-sized circles on the skin. If you notice these signs, dispose of the apple in a way that children and pets cannot access it, such as by putting it in a paper bag or wrapping it in plastic, advises the USDA. Avoid sniffing the fruit, as you may inhale mold spores. This can lead to allergic reactions and breathing problems. Ideally, cut the apple in half and check its core before eating it. According to PennState Extension, some apples, including Fuji, Golden Delicious and Red Delicious, may have a moldy core. Granny Smith apples are less prone to this problem. However, mold does not always spread to the flesh of the fruit. In this case, it’s still edible. Know What to Look for Brown spots inside an apple are no cause for concern. As mentioned previously, ethylene and exposure to oxygen can cause fruit to turn brown. The apple is safe to eat as long as it shows no signs of mold. However, it is best to avoid fruits with bruising, broken skin, and other signs of damage, as they are prone to mold. If you buy bagged apples, check the expiration date. Make sure they don’t show any signs of mold or holes caused by insects. Always buy these fruits before they are fully ripe. A healthy apple should not be soft and should not leak juice. Also check your apples for dark circular lesions and sunken lesions that are light to dark brown. These are all signs of rot, according to the Ohio State University Extension. The spots can spread quickly and cover the entire fruit as the rot progresses. The American Heart Association recommends storing apples separately from other produce. Since they release ethylene gas, they can cause other fruits and vegetables to rot. If you store the apples in the refrigerator, they should last at least a week. When stored on the counter, they will last up to seven days. Remember the old adage “A bad apple spoils the barrel?” » Turns out it’s true. That’s why the USDA recommends wrapping apples separately to keep them fresh longer. Pack them in plastic or paper bags and store them in the refrigerator or a cool, dark place.
