Diospyros kaki

Diospyros kaki is commonly called Japanese persimmon, Chinese persimmon, kaki (from the Japanese name 柿, pronounced [kaki]), kaki persimmon, and Oriental persimmon.[3]

The scientific name Diospyros kaki L. f. may be used erroneously for this plant. However, Diospyros kaki L. f., published in 1781, is a later homonym of Diospyros kaki Thunb., published in 1780. So the name Diospyros kaki L. f. is taxonomically illegitimate and not accepted.[4][5]

A kaki tree in Nanyo City, Yamagata, Japan in October 2005.

Similar in shape to an apple tree, the kaki tree reaches a size of up to 10 metres (33 ft). Its deciduous leaves are medium to dark green, broadly lanceolate, stiff and equally wide as long. Blooming from May to June, the trees are typically either male or female, but some produce both types of flowers. Furthermore, the sexual expression of a tree may vary from year to year. Unusually, the kaki fruits ripen when the leaves have mostly fallen off the tree, typically in October and November. (Northern Hemisphere)

Kaki trees typically do not bear until they are 3 to 6 years old. The 2 centimetres (1 in)-2.5 centimetres (1 in) wide flowers appear in late spring or early summer depending on variety and growing area. The tubular flowers have a creamy white color. Female flowers grow singly, while male flowers sometimes may have a pink tint and tend to appear in clusters of three. Diospyros kaki is typically a dioecious species which means that trees are either male or female but some cultivated varieties are monoecious in which case both male and female and even perfect (male+female) flowers can be found on the same tree. The flowers have four crown-shaped sepals and four petals that form a large calyx.

All varieties (parthenocarpic) will produce seedless fruit in the absence of pollination, but their pollinated flowers will produce more fruit riddled with seeds. Kaki typically suffers very important fruit drop. The first flush of fruit drop happens shortly after flowering when +/- 50% of the fruit will drop. The second flush happens in August when again an important amount of fruit will drop. After this, the rest of the fruit will usually stay on the tree and mature. Fruit drop depends on climatic conditions and water availability. Pollination is not necessary for fruit set but may help to reduce fruit drop after averse climatic conditions or drought periods.

Two kaki fruits, one cut open.

The fruit of Kaki. Plaquemine (Fr). Kaki (En). Japanese persimmon, kaki persimmon. (Diospyros kaki Thunb., 1780)

The persimmon is an edible 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, including Japan where it is very popular. It was later introduced to California and southern Europe in the 19th century, to Brazil in the 1890s,[6] 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.

The spherical to oval fruit, bearing the indented stem and four sepals, can weigh up to 500 grams (18 oz). 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 a raw unpeeled chestnut, which becomes weaker with progressive maturation. The furry taste, caused by the tannins, is reduced and finally completely disappears during the ripening process.

Apart from tannins, triterpenoid compounds such as α-amyrin, uvaol, ursolic acid, 19α-hydroxy ursolic acid and 19 α,24-dihydroxy ursolic acid can be isolated from the leaves of D. kaki.[7]

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.[8]

Variety "Koushu-Hyakume" (astringent - for making dried kaki)

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.

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 trade name for the "Triumph" variety grown in the fertile Plain of Sharon in Israel. It is a PCA variety which is always treated with CO2 gas to remove astringency before it is marketed. This kaki has a rather squarish shape and it has one of the highest sugar contents of all varieties. It also has a very firm skin unlike most other varieties. because of this it has good keeping qualities and it doesn't suffer to much during handling.

In Spain, the most important kaki variety is "Rojo Brillante". This PCA variety is mostly grown in the Valencia region in a protected region of origin (DOP) called the "Ribera del Xuquer". During the last decade a CO2 treatment procedure has been perfectioned by which nearly all Rojo Brillante kakis are treated to remove astringency while still retaining their firmness and keeping qualities. This treated kaki fruit is marketed as Spanish Persimon (with one 'm'). Because of this treatment, the "Rojo brillante" kaki has turned into an easily edible fruit which has become highly appreciated in the whole of Europe and beyond. Because of this commercial success the production of "Rojo brillante in the last decade has hugely augmented.

In Italy the most widely grown variety is "Tipo" (PCA) and some other varieties in smaller quantities. Italy used to be the largest kaki exporting country in Europe but export has diminished significantly due to the success of the Spanish kaki export. This drop in export is entirely due to the fact that until now Italian kakis are not CO2 treated and thus can only be eaten after they have turned soft. Italy has recently developed a CO2 treatment procedure that can be used on the Tipo variety but it is not commonly used yet. This might help in regaining part of the export in the future.

Kaki is also produced in Albania, mainly in the Elbasan region. Since 1935–40, it is also grown in small quantities in Bulgaria, particularly in the Upper Thracian Plain and on the Bulgarian Black Sea Coast.[9][10]

In astringent cultivars (cultivated varieties), the fruit has a high proanthocyanidin-type tannin content which makes the immature fruit astringent and bitter.[11] The tannin levels are reduced as the fruit matures. The fruit of those cultivars is not edible in its crisp, firm state; they're edible when soft ripe. The ripe fruit has a soft jelly-like consistency. The Japanese 'Hachiya' is a widely grown astringent cultivar. Other cultivars, such as 'Fuyu', do not contain tannins when firm. Those 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, however, considered to have a less complex flavor.[12]

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.

A vase adorned with a kaki cake, a pine branch and an orange is a symbol of the desire for "great happiness in 100 affairs."

Fuyu persimmon

Dried persimmon in the making

The leaves are commonly removed before serving. Though the skin is often removed, it may be eaten -- especially when the fruit has ripened and the tannins have significantly broken down, reducing the acridity. They can also be dried; two fruits are attached to a string which is then hung over a pole.

In Korea, the persimmon is called gam (Korean: 감), and it is usually eaten as a dessert or when there are guests at home. The persimmon is cut into sections and the skin and core is usually removed. Persimmons are eaten dry during the winter, and they are very popular amongst children. In autumn, families and farmers from the rural areas collect persimmons and hang them to dry. Powdered sugar is sometimes added to enhance the sweetness.

Persimmon vinegar may be made from Oriental persimmons.