Do you like your pastries golden brown and crispy? Think twice, suggests international project.

Who doesn't like the comforting smell of a bakery in the morning, a mixture of coffee and freshly baked bread, crisp rolls and crunchy cakes? But according to a European research project, in which Czech scientists are also taking part, the tasty golden brown pastries with a thick and crisp crust may not be such a good idea after all.

Some ordinary foodstuffs, especially baked products, have recently been found to contain a hazardous chemical which can cause cancer. What is that substance and where does it come from? - a question I put to Professor Jana Hajslova, the head of the Czech team participating in the research.

Professor Jana Hajslova
"Let's say, five years ago, I would not be able to answer this question. However, at the beginning of this century, there was breaking news in scientific literature and the headline of the first paper was 'Acrylamide - a cooking carcinogen?'. When I read this paper I didn't know at all what the question was about. However, later on, the research progressed and Swedish scientists announced that in bread and many other baked foodstuffs, there is a dangerous carcinogenic chemical called acrylamide. It is a very simple compound, nothing special in terms of structure. It was proved that this chemical originates from very simple compounds that are contained in many ingredients that are used for the production of baked products."

The EU project, titled Heatox, or Heat-generated Food Toxicants: Identification, Characterization, and Risk Minimization, has found that acrylamide is formed from the most basic ingredients in heat-treated food rich in carbohydrates.

"These compounds - we call them precursors - are glucose, which is a very simple sugar, and asparagine, which is a very simple amino acid. The reaction through which they are formed is called 'the Maillard reaction' or sometimes we call it non-enzymatic browning. In principle, this reaction is very beneficial for food technologies and also consumers because it leads to the formation of aroma compounds. Also food texture and colour is formed in this way."

When the chemical was identified in the foodstuffs, the primary tasks were to find out how acrylamide is formed and how to mitigate its formation and reduce its content. The European Commission launched a scientific project led by a team from Lund University in Sweden. The project brings together experts from various EU countries, including the Czech Republic. Professor Jana Hajslova, the head of the team from the Department of Food Chemistry and Analysis of Prague's Institute of Chemical Technology, says the Czech Republic has been the only new EU member state represented in the project.

The five-year project is now approaching its end. Next week, the final Heatox meeting will be held in Prague to summarise the outcomes and future challenges for follow-up research. What are the practical implications of the findings for both households and the food industry?

"One of the very general advices is whenever you bake your bread or whenever you bake your cakes and so on, or when you prepare your potato chips, be careful with the duration of the heating process, the frying process, and stop your cooking as soon as the colour is golden, golden brown. Don't go into deeper colours because that is the phase when acrylamide is intensively formed and when its levels are rapidly increasing and the final product is rich in this toxic chemical."

Keeping your pastries pale is one way to reduce the levels of acrylamide in your food. Besides that, certain chemicals but also natural ingredients of baked products have been found to keep acrylamide at bay.

"Although there is no possibility to eliminate it completely, it is possible to reduce its levels in the final product. For example, the outcome of the Heatox project is information on the positive effect of fermentation, that means using baking yeast for bread production. It helps to remove the precursors and consequently reduces the final levels of acrylamide. Also, a very new strategy is using enzymes which decompose asparagine amino acids in the original ingredient. As soon as this compound is eliminated, the heating process doesn't lead to acrylamide formation. Now, of course, there is an effort to enable the use of a relatively expensive enzyme also on an industrial scale. Of course, it initiates attempts to make the production of this enzyme cheaper using biotechnologies, for example, and to make it available for conventional production of these baked products."

You may be thinking now that generations of people have been eating bread and other baked products without ever falling sick. Jana Hajslova explains.

"A question, of course, could be expected how it is possible that we've been eating a carcinogenic compound in our foodstuffs and what is the risk for consumers. I should say that it is an issue which has not been finally assessed because the risk analysis is still running. There are, of course, many chemicals which, contrary to acrylamide, exhibit protective effects and compensate the toxic effects of other chemicals. We can also rely on anti-oxidants and many other dietary components that are able to diminish, to reduce the toxic effects of other chemicals."

The commonsense advice seems to be as in many other areas of life - everything in moderation. Everything is potentially toxic if consumed in large quantities. So can a balanced diet keep you safe from the effects of acrylamide?

"Food science and toxicologists are trying to find out the answer to this question. The general advice is to keep your diet as rich as possible, with a lot of diversity. Don't forget to eat a lot of fruits and vegetables and don't eat only chips, or crisps or French fries. That is, of course, not only because of acrylamide but also the high content of fat in them is dangerous. We cannot identify acrylamide as the only hazard in your diet but it is one on the components that was recognised to be dangerous when the intake is excessive. I would say that under normal conditions when the diet is really diverse, you don't need to be worried about the risk associated with this chemical."

The Czech team that took part in the EU Heatox research are now working on a related project. They are examining traditional Czech baked products, like pastries and breads, and monitoring the occurrence of acrylamide. They are collaborating with the food industry in order to apply the knowledge obtained in Heatox in local conditions, teaching the people from the food industry how to improve the technologies to get a safer final product.