French fries exposed to a taurine solution prior to frying contained 96 per cent less acrylamide than control fries, according to new data published in Food Research International.
“Thus, taurine, when used in a narrow range of reasonably low levels, is a candidate to inhibit acrylamide formation during frying process,” report the researchers from the Korea University, Namyang Dairy Products Co., and the Korea Food Research Institute.
Taurine, a derivative of the amino acid cysteine, if found naturally in foods including seafood and meat. It has gained a certain notoriety by being used as an ingredient in energy drinks, with some national regulators questioning the safety of the ingredient. Taurine is used in energy drinks because some report it helps boost energy – a claim that was rejected by the European Food Safety Authority (EFSA) recently.
With regards safety, EFSA’s Scientific Panel on Food Additives and Nutrient Sources Added to Food found no safety issues for taurine or D-glucurono-y-lactone at average daily energy drink consumption of 0.5 cans.
Since taurine can participate in the Maillard reaction that produces acrylamide, the researchers investigated if taurine could reduce the levels of acrylamide in French fries. They found a dose-dependent reduction in acrylamide levels when French fries were soaked in a taurine-solution prior to frying. Indeed, levels were reduced by up to 96 per cent, depending on the concentration and pH of the solution, said the researchers.
The findings are very promising, and the researchers confirmed that work was continuing in this area. “In the future, we plan to characterize the relationship between taurine concentration and its inhibitory activity against the formation of acrylamide,” they stated.
The acrylamide story
Acrylamide is a suspected carcinogen that is formed during by heat-induced reaction between sugar and an amino acid called asparagine. Known as the Maillard reaction, this process is responsible for the brown colour and tasty flavour of baked, fried and toasted foods.
Despite being a carcinogen in the laboratory, many epidemiological studies have reported that everyday exposure to acrylamide in food is too low to be of concern.
The compound first hit the headlines in 2002, when scientists at the Swedish Food Administration first reported unexpectedly high levels of acrylamide, found to cause cancer in laboratory rats, in carbohydrate-rich foods.
Since the Swedish discovery a global effort has been underway to amass data about this chemical. More than 200 research projects have been initiated around the world and their findings co-ordinated by national governments, the EU and the United Nations.
A toxicology study reported at the end of last year that tolerable intakes of acrylamide should be set at 2.6 micrograms per kilogram of body weight to avoid the cancer risk.
According to findings published in Food and Chemical Toxicology, (doi: 10.1016/j.fct.2009.11.048) this would be equivalent to 182 micrograms for a 70 kg human as a tolerable daily intake (TDI) for carcinogenic levels. The TDI for neurotoxicity was found to be higher, at 40 micrograms per kg per day, or 2,800 micrograms per day for a 70 kg human.
Both levels vastly exceed levels estimated by various national agencies or studies. Health Canada, for example, estimates the average exposure of adults to acrylamide in food to be between 0.3 and 0.4 micrograms per kilogram of body weight per day, while a study from Sweden estimated intakes of about 0.5 micrograms per kilogram of bodyweight. The US Food and Drug Administration (FDA) estimated intakes to be around 0.4 micrograms per kilogram of bodyweight per day.
Source: Food Research International
Published online ahead of print, doi: 10.1016/j.foodres.2010.03.024
“Reduction of acrylamide by taurine in aqueous and potato chip model systems”
Authors: D-C. Shin, C-T. Kim, Y-C. Lee, W-J. Choi, Y-J. Na, K-W. Lee