Nectarines are essentially the same fruit as peaches. The main difference is that nectarines have a smooth skin and a firm flesh and peaches are fuzzy.
The smooth skin that defines nectarines is a minor genetic variation, so it is not uncommon for a peach to produce a branch that bears nectarines, or vice versa.
As with peaches, nectarines can be white or yellow. Yellow nectarines have higher sugar content than white nectarines, but white nectarines usually taste sweeter due to their lack of acid.
Nectarines are low in fat, free of saturated fat, sodium, and cholesterol, and are a good source of Vitamins A and C.
California grows over 95% of all nectarines in the United States!

Salon.com
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