The Kiwifruit is an edible berry of a woody vine in the genus Actinidia, and comes in a numerous variety of cultivars, all of which produce multiple fruits. The most common of the cultivar groups of kiwifruit is oval, about the size of a large hen’s egg; 2-3 in (5-8 cm) in length and approximately 1.8-2.2 in (4.5-5.5 cm) in diameter. The plants have a fibrous, dull greenish-brown skin and bright green or golden flesh with rows of tiny, black, edible seeds. The fruit has a soft texture and a sweet but unique flavor, and today is a commercial crop in several countries, such as New Zealand, Chile, Italy, France, and Greece. Kiwifruit is endemic to China.
Kiwifruit plant can be grown in most temperate climates with adequate summer heat. Where fuzzy kiwi (the most common variety) is not viable, other species can be grown as substitutes. Kiwifruit is commercially grown on sturdy support structures since it can produce several tons of fruit per acre! This is more than the rather weak vines can support. These are generally equipped with a watering system for irrigation and frost protection in the spring. Kiwifruit vines require vigorous pruning, similar to that of grapevines. Fruit is borne on one-year-old and older canes, but production declines as each cane ages.
Kiwifruit Pollination and Reproduction
Canes should be pruned off and replaced after their third year. Most of the varieties are dioecious and require a male plant to pollinate a female plant for the female plant to produce fruit. For a good yield of fruit, one male vine for every three to eight female vines is required. Other varieties can self-pollinate, but they produce a greater and more reliable yield when pollinated by male kiwifruit vines. Kiwifruit is notoriously difficult to pollinate because the flowers are not very attractive to bees.
Generally, the most successful approach, though, is saturation pollination, where the bee populations are made so large (by placing hives in the orchards) that bees are forced to use this flower because of intense competition for all flowers within flight distance.
Kiwifruit Chemical Compounds
Raw kiwifruit is rich in the protein-dissolving enzyme actinidin, which is commercially useful as a meat tenderizer. Actinidain also makes raw kiwifruit unsuitable for use in desserts containing milk or any other dairy products which are not going to be served within hours, because the enzyme soon begins to digest milk proteins. This applies to gelatin-based desserts, as well, as the actinidain will dissolve the proteins in gelatin very quickly, either liquefying the dessert or preventing it from solidifying.