Food scientist favours flavonoids

Heart healthy flavonoids, often removed in processing because they are bitter, could actually improve the taste of certain food products, reports a scientist in the US. Clearing the way for a boost of flavonoid fortification in food.

Adding heart healthy flavonoids to food during processing can improve the taste of some products, despite their bitter profile, claims a US scientist.

Increased consumption of flavonoids, which occur naturally in plant foods, has been associated with reduced risk for cardiovascular disease. However, flavonoids are often removed in processing because they are bitter.

Research from Penn State University in the United States shows that the presence of flavonoids at levels that benefit cardiovascular function does not automatically increase bitterness but can actually promote good flavour development and palatability in some food products.

Dr Devin Peterson, assistant professor of food science and director of the study, said: "Our research has shown that in food and beverage products that are heated for safety or preservation, flavonoids can limit the generation of off-flavours, such as the scalded or cooked taste of ultrapasteurised milk. We've also found that it may be possible to enhance some good flavour pathways while limiting others, including less desirable smells, by the addition of flavonoids."

Presenting the results at the American Chemical Society meeting in New York yesterday, Peterson explained that three different levels of epicatechin, a flavonoid typically found in fresh fruits, vegetables, tea and chocolate, were added to whole milk and before being ultrapasteurised. Tests with a trained panel of tasters found that all samples containing the flavonoid were significantly lower in cooked flavour and one was indistinguishable from regular pasteurised milk, which has no cooked flavour at all.

Experiments with a granola bar mix to which epicatechin had been added showed that the flavonoid inhibited the formation of some flavour constituents produced in browning, including a powerful flavour/off flavour regulator. Nevertheless, taste testers did not detect an increased level of bitterness in the epicatechin-enriched granola bar versus the control.

In other experiments, the power of epicatechin to affect flavour was demonstrated when the flavonoid was added to unroasted cocoa and then heat processed. The flavonoid reduced by half the production of the two major flavour constituents.

"Adding flavonoids to food products at efficacious levels does not have to result in increased bitterness and consumer rejection. By understanding how health-promoting flavonoids alter flavour generation, we can learn how to produce healthier foods that taste good too," said Peterson.