Fruit extracts offer promise for acrylamide cuts

Extracts from apples may inhibit the formation of acrylamide in potato chips, offering formulators an alternative to reduce levels of the suspected carcinogen.

Addition of 35 milligrams of apple extract reduced the formation of acrylamide by over 35 per cent, while other fruit extracts failed to produce any benefits, according to findings in the Journal of Agricultural and Food Chemistry.

“The findings of the present study provided useful information for the development of natural food additives that could be relevant to mitigation of acrylamide-associated health risks in practical applications,” wrote researchers from the University of Hong Kong, Hong Kong Baptist University, and Jinan University.

The study potentially adds another option to formulators seeking to reduce the acrylamide content of their fried or baked foods.

Approaches already used by the food industry to help reduce acrylamide levels include converting asparagine into an impotent form using an enzyme, binding asparagine to make it inaccessible, adding amino acids, changing the pH to alter the reaction products, cutting heating temperatures and times, and removing compounds from the recipe that may promote acrylamide formation.

Enzymes such as DSM’s Preventase and Novozyme's Acrylaway, work by converting asparagine into aspartic acid, thereby preventing it from being converted into acrylamide. The effect is a reduction in acrylamide in the final product by as much as 90 per cent.

While the new study reports acrylamide reduction of only about 35 per cent in the final product for apple extracts, there may exist room for improvement.

The researchers focused their attention on the components of the apple extracts and found that “proanthocyanidin-rich sub-fraction played a key role in mediating the inhibitory activity”.

On the other hand, extracts from blueberry, mangosteen and longan did not have any beneficial effect on acrylamide levels, while extracts from dragon fruit actually increased levels of the compound, added the researchers.

“The present study identified some natural products that might have important applications in the food industry to inhibit acrylamide formation,” they added.

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.

Source: Journal of Agricultural and Food Chemistry

Published online ahead of print, ASAP Article, doi: 10.1021/jf902529v

“Effects of Fruit Extracts on the Formation of Acrylamide in Model Reactions and Fried Potato Crisps”

Authors: K-W. Cheng, J-J. Shi, S-Y. Ou, M. Wang, Y. Jiang