Acrylamide is a compound that is not added to foods but that forms naturally from a reaction of sugars with some specific amino acids found during certain types of heat processing and cooking. Acrylamide has been present at some level ever since we began cooking, but it was first identified in food in April 2002, when a group of Swedish scientists presented research that detected trace levels of the compound in some baked and fried foods. Prior to the Swedish study, food was not analyzed for acrylamide because it was not used as an ingredient, nor was it known to be a component of food.
In light of the finding from the Swedish study, the food industry, world health organizations and scientists throughout the world have increased their attention to acrylamide. Food regulatory agencies from several countries, including the US Food and Drug Administration (FDA) have initiated several studies regarding acrylamide in food. Although the initial studies found that acrylamide can be detected in baked and fried foods, further work including research from FDA found varying low levels of acrylamide (measured in parts per billion) in a broad variety of foods.
There is no evidence that the amount of acrylamide in food is harmful to humans. Significant questions remain regarding the true risk of acrylamide in foods.
International leaders in acrylamide research from academia, industry, and government also met recently to discuss recent findings and to identify areas in need of additional research. The Second Joint Institute for Food Safety and Applied Nutrition (JIFSAN) Acrylamide Workshop was held in Chicago, Illinois, in April 2004 (the first meeting having been held in October 2002). A few highlights of the 2004 meeting are summarized here.
Acrylamide forms from a reaction of carbonyls—specific carbon and oxygen components of reducing sugars like glucose or fructose—with certain amino acids, which are the building blocks of protein. Asparagine is the amino acid primarily involved in the formation of acrylamide and is commonly found in its free form (i.e., not linked with other amino acids in proteins) in many foods. The main mechanism of formation results from the Maillard browning reaction, which is responsible for the brown crust on bread and the toasty color and flavor of some breakfast cereals. Acrylamide thus forms in foods that are subjected to high temperature preparation processes such as baking, frying, and canning.
FDA’s analysis of the foods in the U.S. diet found acrylamide in many samples at varying low levels and more detectable in potatoes, bread, and cereal products, but it can be found in other cooked and processed foods, prepared in restaurants or at home. Processing/cooking times and temperatures have been shown to affect the levels of acrylamide formed.
Although the amount of acrylamide consumed from home-prepared foods is unknown, research has identified home food preparation methods consumers can use to reduce the levels of acrylamide formed during cooking. Lauren Jackson, Ph.D., of the FDA Center for Food Safety and Applied Nutrition, National Center for Food Safety & Technology in Summit-Argo, Illinois, noted that most of the acrylamide formed during the toasting of bread was found in the darker portions of the toast. When this portion of the toast was scraped off the bread, the "toast scrapings" had significantly larger amounts of acrylamide than the remainder of the toast.
Dr. Jackson also reported the effects of frying times and temperatures on acrylamide formation in French fries. Consistent with the levels obtained on toasted bread, acrylamide levels and the degrees of browning increase with cooking (frying, toasting, etc.) times and temperatures. The degree of browning may be used as an indicator of the levels of acrylamide formed in some foods during cooking or processing. Additionally, to reduce acrylamide levels when frying fresh potatoes, storage of the potatoes in a cool (but not refrigerated), dry, dark room is important. This will prevent accumulation of sugars as well as sprout formation. She also noted that some washing treatments, including soaking and rinsing the sliced or cut potatoes in plain water, are effective in reducing acrylamide levels in the final cooked potato products.
In another evaluation of acrylamide in foods, in May 2004, the National Toxicology Program’s Center for the Evaluation of Risks to Human Reproduction (NTP-CERHR) convened a panel of experts charged with the task of providing a scientifically sound evaluation of whether the current general population exposure to acrylamide poses a risk to human reproduction and development. For three days, the 14-member panel synthesized data from nearly 125 research papers into a cohesive report on acrylamide’s reproductive and developmental effects on humans. The panel noted that although studies with animals suggest that acrylamide is harmful to reproductive and development processes in rats and mice, sufficient data are not available to reach the same conclusion regarding human exposure to the chemical. "Considering the low level of estimated human exposure to acrylamide derived from a variety of sources, the Expert Panel expressed negligible concern for adverse reproductive and developmental effects for exposures in the general population," concludes a June 2004 report available on the NTP-CERHR Web site (). "After reviewing all existing data quite extensively, we now know we need more research to find out if humans are at risk," Michael Shelby, director of the NTP-CERHR, concluded.
Food processors are also looking for ways to reduce the levels of acrylamide that are formed in their products while maintaining the same quality and safety of their products. There are many unanswered questions about acrylamide in foods, but the government, industry, and academia are committed to additional research to be certain that any risk to humans is minimized. Most scientists agree that all foods can be consumed as part of a healthful lifestyle. The optimum diet is most easily achievable if food choices are made on the basis of moderation, balance, variety, and enjoyment. In that spirit, the FDA and the World Health Organization do not recommend any dietary changes on the basis of what we now know about acrylamide. In fact, FDA continues to recommend that consumers eat a balanced diet, choosing a variety of foods that are low in trans fat, saturated fat, and rich in high-fiber grains, fruits, and vegetables.
Can I Reduce Acrylamide Levels in Food?
Until more is known about acrylamide in food, experts from FDA recommend that consumers focus not on acrylamide, but on eating a balanced diet, choosing a variety of foods that are low in trans fat and saturated fat, and rich in high-fiber grains, fruits, and vegetables. However, if you are still interested in reducing the trace levels of acrylamide that may be present in food, here are a few tips for home cooking:
- Avoid overcooking or using extremely high temperatures in cooking food. (NOTE: Undercooking some foods may result in foodborne illness.)
- Fry foods to a LIGHT, rather than dark, golden brown.
- Scrape the darker crumbs off toast and other baked items before consuming.
- Store potatoes at room temperature in a dry location, then soak and rinse cut or sliced potatoes, before frying or baking. It is important to drain the potato slices before frying to prevent pan fires.
- Enjoy a moderate amount of a wide variety of foods to stay healthy!
