Acrylamide levels low in UK diet

In April 2002, acrylamide came to the attention of the food industry when scientists at the Swedish Food Administration first reported unexpectedly high levels of this harmful chemical in carbohydrate-rich foods.

Acrylamide is formed naturally when these foods are fried, baked, grilled, toasted or microwaved at high temperatures, for example chips, roast potatoes, crisps and bread.

Since then, more than 200 research projects have been initiated around the world with their findings co-ordinated by national governments, the European Union and the United Nations.

Contributing to the international programme, the UK Food Standards Agency (FSA) study set out to estimate the amount of acrylamide people are exposed to from the average UK diet, with sampled foods prepared according to normal domestic practice.

Confirming previous findings, the FSA reports: "Acrylamide was quantified in 7 of the 20 food groups tested. The dietary exposure estimates show that cereal-based products and potatoes are the main sources of acrylamide in the UK diet."​

Quantifiable amounts of acrylamide were found in bread, miscellaneous cereals - including products such as biscuits and breakfast cereals, poultry, meat and meat products, sugars, preserves and potatoes (a range of cooked fresh and processed potatoes).

The FSA also aimed to identify whether previously unconsidered food categories contributed significantly to exposure to this potential carcinogen, but according to their findings no new sources of dietary acrylamide were identified.

"The results of this survey do not affect FSA advice on what people should eat,"​ said the government-funded body this week in a bid to dampen any 'knee-jerk' reactions.

Their findings will be fed into the February 2005 Joint FAO/WHO Expert Committee on Food Additives safety evaluation of acrylamide in food.

Progress continues to made in the field. Following the Swedish findings in 2002, breakthrough research led by Professor Don Mottram at the University of Reading took a substantial step forward by looking at how the chemical could be formed.

Mottram's team suspected it could be created by a reaction between an amino acid called asparagine, which occurs naturally in relatively high levels in potatoes and other cereals, and sugar.

Tests confirmed that when the amino acid is heated, it does react with sugar to create acrylamide, a process called the Maillard reaction. This occurs at temperatures above 100°C (212°F). Their findings were published in Nature​ 419, 448-449 (2002).

Speaking last year to FoodNavigator.com Professor Mottram said that the industry was still working to monitor the presence of acrylamide in foods and trying to look at empirical ways to gauge the problem.

And as global efforts in food science strive to learn more, DSM Baking Enzymes, a division of Dutch chemicals firm DSM, claims to have designed a way to eliminate acrylamide from bakery products that could appeal to concerned food makers.

The firm applied genomics technology to degrade the free amino acid L-asparagine.​

"Since acrylamide is formed from L-asparagine when food is processed at temperatures exceeding 1200C, DSM experts reasoned that converting L-asparagine in dough prior to baking would prevent acrylamide formation,"​ said the firm in a statement.

This involved screening the 14,000 genes of the Aspergillus niger​ genome - a commonly used micro-organism in the food industry and for which DSM determined the DNA sequence in 2001. A gene encoding L-asparaginase​ was cloned from food-grade Aspergillus niger​ and expressed in its native host. The resulting strain was fermented, and the asparaginase subsequently purified before being added to the dough.

"The result was a significant reduction in acrylamide levels in end-products such as bread and Dutch honey cake,"​ said the Dutch firm, adding that it has filed a patent for the technology and is investigating its potential for application in other areas, including potato crisps.

In particular, the food companies are looking at ways to reduce acrylamide levels by moderating the processing conditions - investigating, for example, certain potato varieties and the impact they can have on the chemical's formation.

Industry has the opportunity of a progress report tomorrow when the European Commission gathers together stakeholders in Brussels for an update on new findings.

Participants from the European Food Safety Authority, the European research project 'Heatox', the Confederation of Food and Drink Industries (CIAA) and consumer group BEUC will, among others, all contribute to the day's meeting.