Strange odors are common in student housing—the humidity of late summer days, old heating pipes kicking in at the start of winter and the various odor remnants left over from weekend festivities.
So last year when sophomore Eric Hockers smelled a pungent odor drifting out of his dorm room closet, he didn't think much of it. It wasn't until he began noticing strange creamy residue on some of his clothes that he decided to investigate. What he found was an old, blackened banana that had been left for several weeks in his closet.
""It was all black, pretty flat and hanging down in between the wires. It was partially dried because it had been there so long, and the banana peeling had a crack in it so the inside was dripping through,"" Hockers said.
While some cases of food spoilage such as this are obvious and common sense can dictate whether to consume the food product, other cases require some knowledge in the area of food safety.
According to UW-Madison food science professor Barbara Ingham, ""The greatest risk that college students face is keeping things [food products] too long.""
Ingham said that when foods are consumed past the expiration date on the package, the nutrient and flavor quality have deteriorated. Most foods that are kept too long do not pose serious health risks, she said, but certain food groups—such as meat and dairy products—do require a strict adherence to the expiration dates.
Refrigeration does provide some protection against microorganism growth, UW-Madison food science faculty associate Robin Kurtz said. However, for refrigeration to be effective, she said the temperature inside must be around 40 degrees Fahrenheit.
Refrigeration does not mean food will keep indefinitely, Kurtz said. To prevent eating bad food, she said one must be conscious of the product's condition. In particular, she said as fruits and vegetables begin to naturally decay, they become more aesthetically unappealing.
Although Ingham said it is always better to favor caution, she added that with browning fruits, ""It's an indication of tissue senescence, death of the tissue, but that does not necessarily mean the inside is unsafe.""
Outside of the refrigerator, meat products can also cause safety implications when left out for too long.
""Hamburger has a lot of microorganisms in it, and when you leave it out, they multiply and reach really high numbers,"" Kurtz said.
According to Kurtz, it is having a high volume of microorganisms that causes a food to rot or mold. The organisms, usually bacteria or fungi, ""are degrading the food product and using it as a food source so that they are just living on it and using its nutrients,"" she said.
The process of molding refers to the growth of fungi that appear on the food as a fuzzy coating. Despite the assumption that mold can be completely removed by cutting off all visible parts, Ingham said this is not true.
""Mold is like an iceberg, and what you see is only a small fraction of what is actually there,"" she said.
While a consumer can be more lenient with cutting mold off of firmer substances like cheese, Ingham said there are still minor health risks. However, foods with a greater liquid composition, such as spaghetti sauce, should be discarded immediately, she said.
Ingham also said uncut fruits have a higher resistance to molding due to a waxy cuticle on their surface that acts as a natural barrier against fungi. However, when there is a cut in the skin or if bruising has occurred, this ""would allow for the tissue to naturally start to die,"" she said. ""That allows for the microorganisms to penetrate into the tissue and grab on and for mold to develop.""
Another important measure to safely eating fruits and vegetables is to thoroughly rinse them off before consumption, both professors said. Careful scrubbing of foods with clear water is still the safest method, they said, and soap products should not be used because they can be harmful when ingested.
Pesticide residue on fruits and vegetables has also become an issue with the increased popularity of organic foods. While there are a variety of fruit and vegetable sprays in the market, Ingham said they may not help with some pesticides, called systemic pesticides.
""[The systemic pesticides] are applied to the root of a plant and are taken up in the vascular tissue and distributed throughout the plant on the inside,"" she said. ""If that is the case, no amount of washing will remove the pesticides.""
Those sprays are effective when a pesticide is externally applied to the plant, Ingham said.
Before perceiving each plate of food as a dangerous mass of microorganisms, Kurtz said that the human body does have high levels of resistance.
""We consume millions of organisms everyday,"" she said. ""We are covered with billions of organisms and the vast majority do not hurt us, and there is only a small percentage of them that cause disease.""
