There are hundreds of different varieties of grapes and most of them are cultivated exclusively for making wine. Only a very few varieties, like the Thompson seedless grapes, Concord grapes and Red Flame grapes are consumed as table grapes.
Difference between Red Grapes and Green Grapes
The reddish-black color of red grapes is due to the presence of flavonoids, an antioxidant. Red grapes are rich in vitamins, especially vitamin C and B, copper, anthocyanins, manganese and potassium. It is also low in calories and high in dietary fiber. A cup of red grapes has around 61 calories which makes it an ideal snack, especially for those looking to lose weight.
Green grapes which are also known as white grapes are available year-round. It is rich in carbohydrates, vitamin C and vitamin K. Green grapes are low in calories, saturated fat and sodium and has zero cholesterol. It contains flavan-3-ols, an antioxidant. Some amount of iron and potassium are also found in green grapes.
Most nutritionists and health experts would recommend consuming more of red grapes. The reason for this would be the high content of antioxidant resveratrol in red grapes, as compared to green ones.
Red grapes contain anthocyanins, a polyphenol, which is absent in white grapes. It is the presence of anthocyanins, which gives red grapes its characteristic color. Anthocyanins are absent in green grapes.
The phenolic content of red grapes is higher than that of green grapes. This is because of the high anthocyanin content in red grapes. Since green grapes do not have this compound, therefore its total phenolic content is low.
Red grapes also contain syringetin, syringetin 3-O-galactoside, laricitrin and laricitrin 3-O-galactoside, which are a class of flavonoids. These flavonoids are absent in green grapes.
Red grapes have a higher level of oxalates than green grapes. High levels of oxalate can contribute to the formation of kidney stones.The polyphenolic, flavan-3-ols is higher in green grapes than in red grapes.The flavonol myricetin is only found in red grapes.
Health Benefits of Grapes
Red grapes contains a flavonoid called resveratrol which helps in lowering high blood pressure and glucose levels. Resveratrol has also been known for lowering the risk of heart diseases. Quercetin, present in red grapes has antihistamine properties required for the treatment of various allergies. Anthocyanin which is present in red grapes has anti-inflammatory properties.
Resveratrol is also known to be the reason behind the French Paradox, which refers to the fact that though the French consume a diet high in fat content they have a low heart disease risk. It is believed that since the French consume regular amount of red wine, they have a lower incidence of heart disease. Grapes also contain high levels of caffeic acid and caftaric acid which act as carcinogenic inhibitor.
Instead of choosing one variety of grapes over the other, you can enjoy both. Grapes are a healthy snack and they have many health benefits. It is also important to note that not all varieties of red and green grapes have the same amount of polyphenols. Difference in cultivars, climate and soil will have an effect on the concentration of polyphenols, and hence the health benefits of grapes.