Acrylamide study points way to processing methods
in processed potatoes can be used to reduce the potential
carcinogen in other products, says a researcher from Dublin.
Enda Cummins, a researcher at University College Dublin, developed the computer model as a means of seeing how closely it co-related with acrylamide production and reduction during processing.
Using the model he was able to forecast with reasonable accuracy the impact each stage of the process had on acrylamide production. The information would allow food companies to focus on the processes that have the most impact in reducing acrylamide.
He presented his results yesterday at the Food Science and Technology conference here in Nantes.
His research is part of the current EU-wide effort to help food companies reduce acrylamide in their products. He developed the model by looking at the whole processing chain, from potatoes are picked in the field, to being turned into chips and crisps and then consumed.
"No other acrylamide study has yet looked at all the stages of producing a food from farm to fork," Cummins told FoodProductionDaily.com, after he unveiled the results of his research. "It could be applied to a wider base of products."
Cummins cautioned however that the model would have to be adjusted to take account of the different relative levels of amino acids and sugars in specific food products. His study was confined to industrial and home production and consumption of chips and crisps in Ireland.
Acrylamide appears to form as a result of a reaction between specific amino acids, including asparagine, and sugars found in foods reaching high temperatures during cooking processes. The process is known as the Maillard reaction. This occurs at temperatures above 100°C (212°F).
Because potatoes have high amounts of amino acids in relation to sugars, it becomes more important for food companies to minimise the sugars so as to reduce the Maillard reaction. The less sugar, the less the reaction.
Cummins was able to figure out how each stage of the potato processing could be used to reduce the formation of the chemical. He found that the use of potato cultivars with low sugar levels was the key factor in reducing acrylamide, as were cooking time and temperature.
"The most effective means of reducing the risk is in the initial selection of cultivars and in the initial levels of glucose and fructose," Cummins said.
Extended frying times above six minutes and above 180 C also increased the risk significantly. Blanching is the next most significant process impacting on acrylamide formation, with reconditioning, soaking and washing having less of an effect at the processing stages.
Cummins' model predicted a mean acrylamide level of 317 micrograms per kilogram in fried potatoes, 720 micrograms per kilogram in crisps, and 1073 micrograms per kilogram in home made french fries. The figures co-related with the levels actually found in the products.
The high levels found in home cooking did not involve the industrial washing and blanching processes
The model, once validated, was then used to generate daily intakes of the chemical in those who ate chips and crisps using data collected on Irish eating habits.
He found that consumption patterns indicated males were eating 0.27 micrograms of acrylamide per kilogram of body weight per day, and females slightly less. Similar low levels were found for crisps. The World Health Organisation recommended daily intake is one microgram per kilogram of body weight per day.
In an interview after his talk Cummins said producing the model for other foods would take extensive time, labour and money. He also noted that the level of human exposure to acrylamide was not as great as previously thought, and that such findings might serve to reduce public concerns.
"Perhaps this is why concern has died down since the initial studies finding it was a possible carcinogen," he said.
Studies indicate that the chemical causes cancer in rats. Toxicological data suggested that this substance might be - directly or indirectly - carcinogenic also for humans.
Acrylamide is created when starchy foods are baked, roasted, fried or toasted. A wide range of cooked foods - prepared industrially, in catering, or at home - contain acrylamide at levels between a few parts per billion (ppb) to over 1000 ppb. The foods include bread, fried potatoes and coffee as well as specialty products like potato crisps, biscuits, crisp bread, and a range of other heat-processed products.
Acrylamide hit the headlines in 2002 when scientists at the Swedish Food Administration first reported unexpectedly high levels of the potential carcinogen in carbohydrate-rich foods cooked at high temperatures. Until then acrylamide was known only as a highly reactive industrial chemical, present also at low levels for example in tobacco smoke.
Since the Swedish discovery a industry-wide effort has been underway to amass data about this chemical. More than 200 research projects have been initiated around the world, and their findings are being co-ordinated by national governments, the EU and the United Nations.
The news, and surrounding controversy over the chemical, jolted the EU's food industry into tackling the issue by looking at ways processing can reduce the levels of acrylamide.
A partnership between the Confederation of the Food and Drink Industries of the EU (CIAA), the EU and national food safety agencies has established a community-monitoring programme for acrylamide.
The monitoring programme focuses on products that are particularly susceptible to acrylamide formation.
An EU programme for consumer advice is due to be established by the European consumer organisation, the BEUC. The framework will form the basis for more specific advice that will be delivered at national level.
Meanwhile the UK and the US have drafted a code of practice on the chemical. It was presented at a Codex committee meeting last April.
