Purple Tomatoes

Joe Schwarcz PhD — Wed, 10 May 2017 18:22:46 +0000

Are you ready for purple ketchup? What about purple pizzas? Scientists in Britain have recently developed a new type of genetically modified tomato enriched with anthocyanin, the pigment also found in blueberries. Various animal studies have shown that this compound, an antioxidant, has proven to be effective in fighting cancers. Perhaps in less than two years’ time, we’ll be seeing purple tomato juice for sale in North America. Consumers stand to benefit directly from this application of genetic modification.

Blackberries and Blue Tortillas

Joe Schwarcz PhD — Wed, 12 Jun 2013 01:01:01 +0000

Chop up and boil some purple cabbage. Take some of the juice, and add a little vinegar. It turns a bright red. Now add some baking soda and watch the juice turn blue. What’s going on? The color of purple cabbage is due to compounds called anthocyanins. In this case, we are looking at anthocyanins that absorb wavelengths of light other than purple, which they reflect. The addition of an acid or a base to these molecules slightly alters their structure and changes their light absorption pattern. But the really neat thing about this experiment is that it can benefit more than your mind. It can benefit your health. All you have to do is eat the cabbage after you’re through ogling the color changes. Those anthocyanins not only absorb light, they also have antioxidant properties, meaning that they can neutralize some of the potentially health damaging free radicals that are a byproduct of inhaling oxygen. The deeper the colour of a fruit or vegetable, the more anthocyanins it contains. That’s why researchers are interested in berries, grapes and even blue corn. Blackberries, being particularly rich in anthocyanins and antioxidant activity, are excellent candidates for health benefits. Researchers at Ohio State University fed diets laced with freeze-dried blackberries to rats after injecting them with azoxymethane, a chemical that causes colon tumours. The results were impressive. The more berries a rat ate, the fewer tumours it had. Read more