There is no direct relationship between the fruit nutrition and health care ingredients with the sweetness content. In general, for the same kind of fruit, taste slightly sour varieties, which the content of vitamins and antioxidant components will be higher.
For example, the special honey sweet and no sour flavor of citrus, the polyphenols content is slightly lower than the sour astringent varieties. This is because most of the good health ingredients more or less have some unpleasant taste, some is acid, or astringent, or bitter, and basically has nothing to do with the sweet.
Of course, not to say that the fruit is bad if tasted sweet, but that if only the sweet taste, no other flavor, health value may not be as good as the rich taste fruit.
Expert introduction, from the angle of delicious, pick fruit on the smelling gas is more reliable, regardless of color, rich aroma of fruit are usually the more delicious.
However, from the nutritional value, there is a reason to choose based on the color, because the color of the varieties are usually better than the color of light. Such as purple and black cherry anthocyanin’s content is higher than the red varieties, red is higher than the Yellow variety. Mango is the same, the flesh orange carotene content is high, and the light yellow one will be slightly lower. For the kiwi, the deep green flesh varieties usually folic acid and VC content is higher, and for the grapes, the purple black, purple red variety antioxidants is higher than green and white varieties.