Researchers from the University of Hong Kong and Rutgers University report that extracts from the fruit inhibited the formation of the genotoxic compounds in fried beef patties, showing the potential of these natural ingredients for processed foods.
"This is the first report showing the inhibitory activities of apple phenolics on the formation of heterocyclic amines," wrote lead author Ka-Wing Cheng in the Journal of Agricultural and Food Chemistry .
"The findings provide valuable information for the development of effective strategies to minimize HA content of cooked meats and to identify several new natural products that may have new applications in the food industry."
According to recent studies, "all-natural" is reported as being the most frequent "positive" new product category.
In 2004, the National Marketing Institute reported that 63 percent of consumers have a preference for natural foods and beverages.
And food sales in natural product stores reached a reported $11.4 billion in 2003.
Tapping into this trend, Cheng and co-workers investigated the potential of the extracts of apple, elderberry, grape seed, and pineapple to inhibit the formation of HAs in the beef patties.
The researchers report that the extracts from apple and grape seed performed most effectively, both by reducing the total HA formation by about 70 percent, relative to the control, and in terms of individual HAs.
Indeed, the formation of 2-amino-3,8-dimethylimidazo [4,5-f]quinoxaline (MeIQx),, and 2-amino-1-methyl-6- henylimidazo [4,5-b]pyridine (PhIP) were reduced by 69 and 59 percent for apple, and 72 and 67 percent for the grape seed, respectively.
In terms of the active components of the fruit extracts, Cheng and co-workers report that the proanthocyanidins, phloridzin and chlorogenic acid reduced the formation of HAs.
"Proanthocyanidins were identified as the dominant inhibitors because they were strongly active against HA formation in both the PhIP and MeIQx model systems," report the researchers.
On the other hand, phloridzin was found to only inhibit PhIP formation.
Chlorogenic acid was effective for inhibiting MeIQx formation, while simultaneously enhancing PhIP formation.
"In conclusion, incubation of beef with selected natural extracts (0.1 percent by weight) before frying can reduce the formation of HAs," wrote the researchers.
"The identification of dominant inhibitors would facilitate selective concentration in favor of these phytochemicals during preparation of natural extracts intended for use in meat preparation and cooking," they concluded.
Source: Journal of Agricultural and Food Chemistry Volume 55, Pages 10359-10365, doi: 10.1021/jf071820z
"Inhibitory Effect of Fruit Extracts on the Formation of Heterocyclic Amines" Authors: K.-W. Cheng, Q. Wu, Z.P. Zheng, X. Peng, J.E. Simon, F. Chen, M. Wang