Clear plastic wrap can mold itself to any food or container, blocking air and moisture.
Nearly every home in America contains at least one box of plastic wrap. While there are multiple non-food uses for plastic wrap, most people use it to seal open containers and protect food from dirt and spoilage as well as to prevent changes in taste, texture and color. It does not matter if you have a lid; plastic wrap fits any size container.
Function
Light, airborne bacteria, oxygen, moisture and temperature are the most common causes of food spoilage. Food safety techniques, such as proper packaging and storage, focus on reducing or eliminating these causes so that food stays safer, longer. Clear plastic wrap blocks out oxygen, moisture, air and airborne bacteria, which is why food packaged with plastic wrap is so common.
History
In 1933, Dow Chemical scientist Ralph Wiley accidentally stumbled upon a brand new plastic--polyvinylidene chloride--best known as Saran. After use in military applications during World War II, Dow introduced Saran wrap plastic film for food and home use in 1953. This stretchable, clingy film could wrap around any shape item and would stick to any substance to create an airtight seal. This seal prevented air and moisture from getting into foods, which prolonged their shelf life and kept them fresh. It was a huge innovation in food safety and packaging.
Safety
The original formulas used in the bulk of plastic wraps contained chlorine and plasticizers that could leach into food and create health problems. Manufacturers have since switched to low-density polyethylene (LDPE) or food-safe versions of polyvinyl chloride (PVC). The new formulas dramatically reduce or eliminate the presence of harmful chemicals such as phthalates and Bisphenol A (BPA) in plastic wrap, so they cannot leach into food and contaminate it. A Good Housekeeping magazine product test of 30 plastic food storage products showed low levels of phthalates and BPA in only one plastic wrap and none in the others.
Misconceptions
There has been a lot of information posted on the Internet about toxins leaching into foods heated in the microwave while covered by plastic wrap. The same Good Housekeeping product test investigated this claim with the help of laboratory testing and found that microwave heating of food, including acidic spaghetti sauce, using all 30 plastic products resulted in no leaching of either toxin into food.
Future
In the future, plastic wrap not only will help us keep food fresh, but also will be able to warn us when it is not. Wraps that change color in response to moisture, air and temperature change are in development. Scientists at Clemson University are working on an antibacterial plastic wrap made of environmentally friendly natural proteins. Researchers are even studying make wraps from fruit and vegetable material that can be converted into a type of marinade.
Tags: plastic wrap, plastic wrap, into food, airborne bacteria, Clear plastic, Clear plastic wrap, Good Housekeeping