By Hwaa Irfan
Chinese/Siberian Gooseberry, Manchurian Pineapple, and Silver/Tara Vine are just some of the English names given to the Kiwifruit. However, these are all different varieties with the kiwifruit in the marketplace being Actinidia deliciosa. The native habitat of Actinidia chinensis, the parent of the cultivated Actinidia deliciosa is the Yangtze River Valley of Northern China and the Zhejiang Province. Known as Yang-tao (strawberry peach) in Chinese, the fruit was introduced to New Zealand at the turn of the 20th century and got the name kiwi after a bird native to New Zealand.
Actinidia chinensis is a deciduous vine of the Actinidiaceae family of the plant kingdom that has a preference for woodland, slope and ravines with moist loamy soil with or without shade, but preferably with exposure to the sunlight. There are male plants, and female plants, which must be grown together in order to propagate. Paper has been made from the bark, which is an insecticide. The edible broad leaves begin life as red-green shoots turning to a deep green as they grow older. In times of famine the nutritious leaves have come in handy. The fruit does not start growing until the second year of planting the deciduous vine. The white – cream fragrant flowers are either male or female bloom from May – June, while the purple-black seeds ripen from October – December. Firm until ripe, the fruit grows up to 3in (7 cm) long becoming full with a sweet juice that has a distinctive flavor of its own. The flesh of the Actinidia chinensis is more yellow than emerald green, and the skin of the fruit is less downy. The flesh is green and contains numerous tiny black seeds, which present no obstacle when being eaten.
It is worth noting that the medicinal properties of kiwifruit differs according to the variety that is being used, the age of the fruit, and the conditions under which it is grown. Currently, 80 compounds have been identified and they include:
- Quinic acid (present in young fruits)
- Ascorbic acid (present in mature fruits)
- Actinic acid
- Bromic acid
- Calcium oxalates
- Ethyl butyrate
- Terpene esters
- Methyl butanone
- Hydroxy – butanone
- Ethyl hydroxybutyrate
- Phenylethyl alcohol
- A-linolenic acid (seed)
- Triterpene phytoalexin
- Arjunolic acid
- Asiatic acid
- Hydroxtormentic acid
Triterpene phytoalexin, arjunolic acid, asiatic acid, atinidic acid, and hydroxtormentic acid have been identified as having high antimicrobial action. Actinidin is helpful in supporting digestion, which for those with slow digestion is beneficial. Its high dietary fiber content supports the health of the colon, and helps to balance blood-sugar levels. Known for its antioxidant properties, Kiwifruit helps to protect DNA for deteriorating although the property responsible for this remains unknown to date. The leading producer of Kiwifruit, Italy found that the more kiwifruit children ate, the more their respiratory problems of wheezing, shortness of breath, and nighttime coughing improved.
It high ascorbic acid content adds to the antioxidant qualities of kiwifruit with a power of 73% compared to the 54% of grapefruit, 46% of lemons, and 40% of oranges. The high carotenoid content ( lutein and xanthine) helps to reduce the risk of age related blindness – macular degeneration, which just happen to be the main carotenoids in the human eye. The A-linolenic acid in the oil from the seeds of the fruit have been found to hydrate the skin and the hair, and as such has been added to cosmetics.
Those with a colon, kidney or gallbladder problem may want to avoid kiwifruits because of its high level of calcium oxalates, which can crystallize in the body preventing absorption of other calcium within the body though the chances of this occurring is minimal. There have also been reports of a range of allergic reactions, which might be related to where and how it was grown. As such, pregnant women and nursing mothers should avoid eating cultivars of actinidia chenensis.
The therapeutic qualities include the following: (see It All Makes Good Scents for definitions)
- Diuretic (fruit, stems, roots, leaves)
- Emollient (seeds)
- Februfuge (fruit, stems, roots, leaves)
- Sedative (fruit, stems, roots, leaves)
- Antimicrobial (pulp)
- Antifungal (pulp)
The fruit, stems, roots, and leaves have been used in the treatment of stones in the urinary tract, for rheumatoid arthralgia, cancers of the liver and the oesophagus. In a study by the Auckland University of Techonology, New Zealand, 42 over 60 year olds with the problem were asked to add kiwifruit to their diet without changing their diet. For 7 of the 42, their daily diet included the taking of laxatives: Mucolax, Lactulose, Isogel, and Codalax, for another two, it was Senokot, and another Normacol once a week. Those who normally ate kiwifruit were asked to not eat kiwifruit for the study. By the end of the study 27 of the participants said they would continue to take kiwifruit because they found that they were able to go more frequently, and with less difficulty, three could not cope with the quantity of kiwifruit consumed as they experienced increase in flatulence, and joint problems, and four had noticed no difference. Given the nature of their diet in general, and possible allergies, the study was successful.
In China the fruit and the juice of the stalk has been used to expel stones, and traditional Chinese medicine, an extract has been used to nourish, cleanse and purify the body, as a face pack, to stimulate collagen, as a diuretic, and to treat haemorrhoids. It has also been used to lower cholesterol, to treat coronary heart diseases, jaundice and to redress the lack of appetite!
Kiwifruit however, is a bit fussy about being processed. It has been found that it loses color, flavor and becomes an irritant to the throat. It loses color if stored under 18°C. Higher in protein and vitamin C than many fruits, the nutritional properties of kiwifruit include:
- Ascorbic acid
- Calcium (fruit)
- Copper (trace amount)
- Folic acid
- Pantothenic acid
- Iron (trace amount)
- Manganese (trace amount)
- Riboflavin (trace amount)
- Selenium (trace amount)
- Thiamine (trace amount)
- Vitamin A
- Vitamin B₆
- Vitamin B₁₂
- Vitamin C
- Vitamin E
- Vitamin K
- Zinc (trace amount)
The fruit we eat of the cultivar Actinidia deliciosa is self fertilizing. It is now grown for the marketplace in Italy (leading producers), Chile, Greece, Japan, New Zealand, South Africa, and the U.S. Harvesting in New Zealand is from May – November, In India from October – December, and in France and the U.S. November, but keep well in storage. If the fruit is firm when bought, they can be kept for up to 8 weeks in a room temperature of 65º to 70º F (18.33º-21.11º C), or in a refrigerator for 10 weeks. Kiwifruits (i.e. Actinidia deliciosa ) are sensitive though to the ethylene that is given off from other fruits if stored in close proximity and will begin to deteriorate/ripen more quickly.
To get the best out of kiwifruit, it is best to use as it is, i.e. uncooked added to salads, the morning meal, desserts, and tarts. It does not blend well with yoghurt because the enzymes in the fruit and the yoghurt conflict. It can be used to tenderize meat by rubbing the meat for not more than 10 minutes, but what a waste of fruit! These same enzymes can make other fruits soggy in a fruit salad, so it is wiser to add kiwifruit just before servimg.
The leaves and branches can be boiled as a decoction for treating mange dogs.
In India the flowers are used as an insecticide against aphids and the rice borer.
In balance He gave us everything we needed, but as for what we want!
“Actinidia Chinensis.” http://server9.web-mania.com/users/pfafardea/database/plants.php?Actinidia+chinensis
Lodge, N and Perera, C. “Processing of Kiwifruit.” http://www.hortnet.co.nz/publications/science/lodge2.htm
Morton, J. “Kiwifruit.” http://www.hort.purdue.edu/newcrop/morton/kiwifruit_ars.html
Rush, E et al. “Kiwifruit Promotes Laxation in the Elderly.” Auckland University of Technology. Asia Pacific J Clin Nutr (2002) 11(2): 164–168
Singh, A. et al. “Popularizing Kiwifruit Cultivation in North East.” http://gbpihed.nic.in/envis/HTML/vol16_1/A.%20Singh.htm