Manufacturers of bakery products looking to reduce levels of acrylamide can tap into a range of solutions, but polyphenols may be the most promising, suggests a new review.
"The most promising field for acrylamide reduction is the addition of low molecular additives such as polyphenols, which have not so far been applied in cereal products," wrote Achim Claus, Reinhold Carle and Andreas Schieber in this month's issue of the Journal of Cereal Science.
"Such additives ideally combine acrylamide reduction with little or no changes in product technology or, most importantly, sensory quality.
"Furthermore, possible health benefits from e.g. polyphenols could even enhance the consumer acceptance of such products."
The review is a timely pooling of the significant and often rapid progress that has been made in acrylamide-reduction, since it first hit the headlines in 2002.
Acrylamide is a carcinogen that is created when starchy foods are baked, roasted, fried or toasted. 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.
And while reducing acrylamide levels is an important target in bakery products, "manufacturers need to keep in mind consumer expectations regarding flavour, colour, and other sensory properties in order to ensure their products remain marketable," wrote the authors from the Institute of Food Science and Biotechnology at Hohenheim University.
The antioxidant approach
Studies are beginning to emerge that show antioxidants may reduce acrylamide levels, with evidence available that ascorbic acid (vitamin C), and rosemary extracts reportedly reducing levels of the potential carcinogen in breakfast cereals, crackers, and even olive oil used for frying.
"Similar observations were reported when a spice mix containing flavonoids was applied to potato crisps, and for the addition of bamboo leaf extracts," state Claus, Carle and Schieber.
The scientific trio go on to state: "According to our observations (unpublished results) polyphenolics had a strong lowering effect on acrylamide formation in wheat bread, which may be explained by their reaction with asparagine.
"Hence, polyphenols appear to be a very potent and valuable additive for acrylamide reduction in different bakery products and more detailed studies concerning this topic are required."
Acidic additives potential
Claus, Carle and Schieber also consider progress made using consumable acids, amino acids, and cations, since these additives offer "a very simple but efficient method to minimise acrylamide in bakery products."
Indeed, studies have already shown that the likes of citric, lactic, tartaric, and hydrochloric acids may reduce the levels of acrylamide in a variety of bakery products, including baked corn chips, semi-finished biscuits and crackers.
The enzyme approach
Another growing area of interest is enzymes. Asparaginase can be employed to turn asparagine into aspartic acid, which prevents acrylamide formation in the Maillard reaction.
At the tail-end of 2007 the Confederation of the Food and Drink Industries of the EU (CIAA) included asparaginase in the new version of its Acrylamide Toolbox, a move seen to validation the efforts of companies that have developed commercial solutions using the acrylamide-reducing enzyme.
This is an area that has seen much heated activity this year as both DSM Food Specialities and Novozymes have commercial products aimed at this area.
However, the Hohenheim-based scientists note: "Although asparaginase addition seems to be very promising for acrylamide mitigation, it is rather expensive compared with other strategies.
"Therefore, it is unlikely that asparaginase will be used to produce low-price foodstuffs such as bread or bread rolls. However, after approval as a food additive, its use for both patisserie articles and coffee appears to be more promising."
Source: Journal of Cereal Science (Elsevier)
March 2008, Volume 47, Issue 2, Pages 118-133
"Acrylamide in cereal products: A review"
Authors: A. Claus, R. Carle, A. Schieber