Heat reduces bioactive compounds and diminishes free-radical scavenging in Mexican peppers

Monday, August 22, 2011 by: Michelle Bosmier
Tags: peppers, raw foods, health news

(NewsTarget) A recent study was conducted by scientists from 3 research institutions in Mexico (the Research Center for Food and Development, the Department of Biotechnology and Food Science at the Sonora Institute of Technology, and the Faculty of Chemistry at the University of San Luis Potosi) and was published in the prestigious journal Food Research International (belonging to the Canadian Institute of Food Science and Technology). The study revealed that heat treatment can severely alter the bioactive compounds and the free-radical scavenging activity in popular Mexican peppers, such as Poblano, Bell, Chilaca, Caribe, Jalapeno, Serrano, Habanero and Manzano.

Peppers are a food staple in Mexico and an important part of local cuisine and culture. While thermally cooked peppers may be responsible for the unique flavors of traditional dishes, Dr. Jose de Jesus Ornelas-Paz and his colleagues warn us that heat treatment deteriorates vegetables on a structural and chemical level and can almost completely destroy ascorbic acid (Vitamin C).

According to the joint research study, raw peppers are a very good source of beta-carotene and other carotenoids, as well as ascorbic acid, which are known to have powerful antioxidant properties. Aside from working as an antioxidant, Vitamin C performs a wide range of functions within the body. It acts as an enzyme cofactor that helps with the biosynthesis of numerous important biochemicals, including collagen, carnitine and tyrosine, as well as with microsomal metabolism.

In chemistry, scavenging refers to the property of a chemical substance to remove or inactivate impurities when added to a mixture. Oxidation produces free-radicals, which can start chain reactions that lead to the damage or even death of cells. Compounds found in raw peppers can thus work on two fronts - by inhibiting oxidation and by removing existing free-radicals via scavenging activity. Since oxidative stress has been linked to numerous diseases in humans, including cancer, cardiovascular diseases and neurodegenerative diseases, a diet rich in antioxidants is believed to improve our health and appearance, as well as extend life-span.

The study additionally reveals that when pungent peppers are either boiled or grilled, significant losses in vital nutrients occur. Ascorbic acid content is reduced by 15-87%, while total carotenoid content can decrease by up to 45%. Moreover, household boiling and grilling of pungent peppers is shown to cause large losses in antiradical compounds (which may be as high as 93%). The Mexican researchers' findings further demonstrate that grilling has a much worse effect on the bioactive compounds in peppers, which may be due to the substantial water losses associated with this method of thermal preparation. Significant color and weight changes also follow grilling, and the researchers have attributed them to the formation of burned tissue. Since burning is an oxidation reaction, the free radical content of grilled foods is considerably higher when compared to boiled or raw foods.

This revealing research study stands in support of the hypothesis that traditional cooking methods, which involve high temperatures, can modify and more often than not lessen the nutritional properties of foods - while almost completely wiping out some of the essential vitamins contained therein.

Sources:

http://caocao.myipcn.org/science?_ob=MImg&_i...

http://www.citeulike.org/article/8624888

http://www.sciencedirect.com/science/article...

About the author

Raw Michelle is a natural health blogger and researcher, sharing her passions with others, using the Internet as her medium. She discusses topics in a straight forward way in hopes to help people from all walks of life achieve optimal health and well-being. She has authored and published hundreds of articles on topics such as the raw food diet and green living in general. In 2010, Michelle created RawFoodHealthWatch.com, to share with people her approach to the raw food diet and detoxification.