Grapes come in a plethora of varieties. There are grapes used for wine, grapes used to make raisins, grapes to eat and, finally, grapes used specifically to make grape-seed oil. There are fundamental differences between grapes depending on their intended use. Wine grapes are small and have thick skins (because most of the aroma for wine comes from the skin), whereas table grapes are seedless, large and have thin skins.
I’ll assume from your question that you mean table grapes as they are the most commonly bought. Table grapes have two different colours; they are either pale green or a dark purple. The difference in pigmentation is due to the production of one gene. This one gene produces anthocyanin. All land plants normally carry Anthocyanin and it is responsible for changing the pigments of flowers, leaves and fruit. Besides pigmentation, anthocyanins attract insects to pollinate and they also act as sun block for leaves by protecting the plants DNA from UV damage. Green grapes carry the gene responsible for making anthocyanins but due to mutations (and the gene pool for table grapes is fairly small) the gene is ‘switched off’ and doesn’t produce anthocyanins. The lack of anthocyanins causes green grapes to stay green.
Apart from colour, the lack of Anthocyanin reduces the antioxidant value of green grapes. So if you are looking for the healthy option then red grapes should be your choice.
Did you know that antioxidants help the body deal with environmental stress and limiting the ageing process? Put down your anti-ageing cream, because nature has provided us with a cheaper (and tastier) solution. So in answer to your question, go for red grapes for the maximum health benefit. And regardless of your grape preference, both options are healthier than a Mars bar.
Question from Jodine via Facebook
Answer by Lucy Huang
Get your questions answered!
Got a question about life, health, nutrition, psychology or science? If there’s something you’ve always wanted to know, or even just something you were pondering whilst taking a shower – let #AskAGuru be the place to go!
We also accept questions via email.
See a list of answered questions here.