The kiwi originated in China and was known as the Chinese gooseberry until New Zealand fruit growers renamed it for their national bird and began exporting it. Today, kiwi fruit is also a commercial crop in California.
Kiwi is bursting with vitamin C. One kiwi has 120 percent of the RDA for this disease-protective vitamin, says Dr. Barry Sears in his book The Top 100 Zone Foods. Besides helping to boost your immune system, vitamin C is an antioxidant that can protect your arteries from the damaging effects of free radicals. Kiwi is also rich in dietary fiber, and a good source of potassium, copper, magnesium, vitamin E, and manganese.
The protective properties of kiwi have been demonstrated in a study with 6- and 7-year-old children in northern and central Italy. The more kiwi or citrus fruit these children consumed, the less likely they were to have respiratory-related health problems including wheezing, shortness of breath, or night coughing. In another study, human volunteers who ate 2 to 3 kiwi fruit per day for 28 days reduced their platelet aggregation response (potential for blood clot formation) by 18% compared to controls eating no kiwi. In addition, kiwi eaters’ triglycerides (blood fats) dropped by 15% compared to controls.
For the sweetest, fullest flavor, choose plump, fragrant kiwi fruit that yield to gentle pressure, like ripe peaches. Unripe fruit has a hard core and a tart, astringent taste. If only firm kiwis are available, ripen them for a few days before eating them. Reject shriveled or mushy fruits, or those with bruises or wet spots.
To ripen firm kiwis — according to the website Wholehealthmd.com — leave them at room temperature, but away from heat or direct sunlight, for a few days to a week. Hasten ripening by placing them in a paper bag with an apple, pear, or banana. Once a kiwi fruit is ripe, however, store it far from other fruits, as it is very sensitive to the ethylene gas they emit, and tends to over-ripen even in the refrigerator. Ripe kiwis should keep for about one to two weeks.