Diospyros kaki, better known as the Japanese persimmon, kaki persimmon (kaki [柿]) or Asian persimmon, is the most widely cultivated species of the Diospyros genus. Although its first published botanical description was not until 1780, the kaki is among the oldest plants in cultivation, known for its use in China for more than 2000 years.
In some rural Chinese communities, the kaki fruit is seen as having a great mystical power that can be harnessed to solve headaches, back pains and foot ache.
The persimmon (kaki) is a sweet, slightly tangy fruit with a soft to occasionally fibrous texture. This species, native to China, is deciduous, with broad, stiff leaves. Cultivation extended first to other parts of East Asia and was later introduced to California and southern Europe in the 19th century, to Brazil in the 1890s, and numerous cultivars have been selected. A variety is Diospyros kaki var. sylvestris Makino. When ripe, this fruit comprises thick pulpy jelly encased in a waxy thin-skinned shell.
In many cultivars, known as the astringent varieties, the fruit has a high proanthocyanidin-type tannin content which makes the immature fruit astringent and bitter. The tannin levels are reduced as the fruit matures. It is not edible in its crisp, firm state; it tastes best when allowed to rest and soften after harvest. It has a soft jelly-like consistency and is best eaten with a spoon. The Japanese ‘Hachiya’ is a widely grown astringent cultivar. Other cultivars, such as Fuyu, do not contain tannins when firm. They can be eaten like an apple or can be allowed to go to any stage of ripeness, including to the jelly-like stage. These non-astringent varieties are considered to have a less complex flavour.
“Sharon Fruit” (named originally after Sharon plain in Israel) is the trade name for D. kaki fruit whose astringency has been chemically removed. It is also known as the “Korean mango”.
Refer also to : Persimmon
The spherical to oval fruit, bearing the indented stem and four sepals, can weigh up to 500 grams. The smooth, shiny, thin shell ranges in shade from yellow to red-orange. The slightly lighter fleshed fruits can contain up to eight seeds and may have an astringent taste. With increasing maturity, the fruit softens, similar to a kiwifruit.
The high content of tannin in the still-immature kaki provides a bitter component reminiscent of pear and apricot flavours, which becomes weaker with progressive maturation. The furry taste, caused by the tannins, is often reduced during the ripening process or by frost. The high content of the carotenoids beta-cryptoxanthin, beta-carotene, and zeaxanthin, along with some lutein and alpha-carotene makes the kaki fruit nutritionally valuable.
Kaki are grown worldwide, with 90 percent of the total in China, Japan and Korea. In East Asia the main harvest time for kaki is in the months of October and November. The trees lose their leaves by harvest time. Occasionally, the brightly colored fruit is left unharvested on the tree as a decorative effect.
In China, kaki has been cultivated since time immemorial. It is considered to have four virtues:
- It lives long.
- It gives a large area of shade.
- It is used by the birds as a nesting place.
- It is not attacked by pests.
Throughout Asia, healing properties are attributed to the kaki. They are said to be helpful against stomach ailments and diarrhea. Immature fruits are said to be a treatment for fever, if they ripen in containers until they are sweet as honey. The juice of unripe fruit is said to lower blood pressure and the fruit stem to relieve a cough. To reinforce these effects, the fruit is peeled before use, exposed to the sunlight during the day and to the dew at night, until a white powdery coating forms.
Cultivation of this species at first spread through East Asia. Since the 19th century, kaki partially replaced date-plum (Diospyros lotus, also known as Caucasian persimmon) in some countries in South Europe and West Asia, because kaki have bigger fruits than date-plum; cultivation in California began at that time.
The “Sharon” is a variegated form of kaki from Israel, named after the fertile Plain of Sharon. It does not contain seeds and tastes more mild, since it clearly contains less tannin. Cross cut, the Sharon shows a star-shaped pattern of lines with darker flesh.
In Spain, there is a variegated form of kaki, the “Ribera del Xuquer” of the Valencia region.
Kaki is also produced in Albania, mainly in the Elbasan region.
Selection and Storage
- Astringent variety persimmon fruits generally harvested while they are hard but fully matured. On the other hand, Non-astringent types can be ready for harvesting when they achieve full-color, and slightly soft in consistency.
- Astringent persimmons usually continue to ripen at room temperature. Both kinds of persimmons should be gathered from the tree using hand-held pruning shears (as in mango), leaving the calyx intact, unless the fruit is to be used for drying, while taking care not to bruise.
- In the stores, select fresh fruits featuring bright yellow-orange colour without any surface bruises or cuts on them. “Dried persimmons” can also be available readily in the supermarkets and feature many similarities to dried-apricots.
- Mature, hard astringent persimmons can be stored inside the refrigerator for several months. Non-astringent varieties have short shelf span and can be stored for only a few days at room temperature.
Preparation and Serving Methods
Persimmons can be consumed fresh, dried, or cooked. Raw fruits can be cut into quarters or eaten wholesome like an apple. Their texture ranges from a firm to mushy and is very sweet.
Here are some serving tips:
- Dried persimmon fruits (hoshigaki in Japan) can be used in cookies, cakes, muffins, puddings, salads and as a topping in breakfast cereal.
- Persimmon Pudding is a popular dessert which uses fresh fruits.
- Dried fruits can be enjoyed as snacks or used in desserts. They are widely employed to make traditional Korean spicy beverage, Sujeonggwa, while a matured, fermented fruit is used to make persimmon vinegar called “gamsikcho”
Health Benefits of Persimmon Fruit
- Persimmon fruit is moderately high in calories (provides 70 calories/100 g) but very low in fats. Its smooth textured flesh is a very good source of dietary fibre. 100 g of fresh fruit holds 3.6 g or 9.5% of recommended daily intake of soluble and insoluble fibre.
- Persimmons contain health benefiting flavonoid poly-phenolic anti-oxidants such as catechins and gallocatechins in addition to having an important anti-tumor compound, betulinic acid. Catechins found to have anti-infective, anti-inflammatory and anti-hemorrhagic (prevents bleeding from small blood vessels) properties.
- Some of other anti-oxidant compounds found abundantly in this fruit are vitamin-A, beta-carotene, lycopene, lutein, zeaxanthin and cryptoxanthin. Together, these compounds work as protective scavengers against oxygen-derived free radicals and reactive oxygen species (ROS) that play a role in aging and various disease processes.
- Zeaxanthin, an important dietary carotenoid, is selectively absorbed into the retinal macula lutea in the eyes where it thought to provide antioxidant and protective light-filtering functions. It, thus, helps prevent “Age-related macular related macular disease”(ARMD) in the elderly.
- Persimmons are also a very good source of vitamin-C, another powerful antioxidant (especially native Chinese and American persimmons; provide 80% of DRI). Regular consumption of foods rich in vitamin C helps the body develop resistance against infectious agents and scavenge harmful, pro-inflammatory free radicals.
- It is good in many valuable B-complex vitamins such as folic acid, pyridoxine (vitamin B-6), thiamin…etc. These vitamins act as co-factors for numerous metabolic enzymatic functions in the body.
- Fresh and dry Persimmon fruits also contain healthy amounts of minerals like potassium, manganese (15% of DRI), copper (12% of DRI), and phosphorus. Manganese is a co-factor for the enzyme, superoxide dismutase, which is a very powerful free radical scavenger. Copper is a co-factor for many vital enzymes, including cytochrome c-oxidase and superoxide dismutase (other minerals function as cofactors for this enzyme are manganese, and zinc). Copper is also required for the production of red blood cells.