"Calcium chloride, as a food additive (E 509), is widely used as a firming agent during processing. It could now be used by the food industry to control the formation of acrylamide," wrote Vural Gokmen and Hamide Senyuva in the journal Food Chemistry.
Acrylamide is a carcinogen that is created when starchy foods are baked, roasted, fried or toasted. It 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.
The researchers, from Hacettepe University and the Scientific and Technical Research Council of Turkey, report that by immersing the potato crisps and French fries in the calcium chloride solution prior to the frying process, could reduce the formation of this cancer-causing compound.
"Potato products such as French fries and crisps were among the food items containing highest amounts of acrylamide," said the authors.
The cut potatoes were immersed in a solution of calcium chloride for 15, 30 or 60 minutes and then fried in sunflower oil for five minutes at 170 degrees Celsius, to enable the Maillard browning reaction to occur.
"It has been shown that Maillard-driven generation of flavour and colour in heated foods can be linked to the formation of acrylamide," explained the authors.
They report that without any calcium chloride addition, acrylamide formation exceeded 700 micrograms per kilograms of potato. This was significantly decreased however on immersion in the calcium chloride solution, with acrylamide levels decreasing with respect to dipping time.
"When compared to the amount of acrylamide formed in potato strips without pre-treatment, percentage inhibition of acrylamide formation increased to ca. 95 per cent by dipping in calcium chloride solution for 60 min at room temperature," wrote the researchers.
Analysis of the sensory attributes of the resulting fries, in terms of golden yellow colour, crispy texture and salty taste, was also performed, and the researchers report that the French fries with added calcium chloride had similar surface colour to that of the control.
"This was the evidence that the Maillard reaction had taken place on the surface of the potato strips, leading to the formation of colour without the formation of acrylamide," they said.
The crispiness of both the control and experimental fries was also said to be similar.
Additional research is clearly merited to elucidate the mechanism by which the extract inhibits acrylamide formation, and whether any new intermediates are formed during the Maillard reaction.
Source: Food Chemistry Published on-line ahead of print; doi: 10.1016/j.foodchem.2006.08.011 "Acrylamide Formation is prevented by divalent cations during the Maillard reaction" Authors: V. Gokmen, H.Z. Senyuva