The persimmon or kaki is a tropical fruit of more or less orange colour, of smooth skin and a very sweet taste. It is consumed as fresh fruit, although it is also used in cakes or jams. It is an important source of vitamins A and C. There are mainly three species of kaki, the Chinese, the Japanese and the species from Virginia. The traditional varieties were astringent, but in the newly obtained varieties this characteristic has been reduced up to a great extent. In general it is consumed fresh.
It is edible when soft, with transparent skin, so it is eaten with a spoon. It is possible to eat it dried or as part of puddings, pies or jams. Its nutritious importance lies in its vitamin wealth, mainly vitamin A and C. It also provides small amounts of vitamin B1, B2 and B3.
Types and Varieties of Persimmon
There exist three species of persimmon: the Chinese, the Japanese and the species from Virginia. The first one is the most cultivated species, whereas the latter usually grows wild. The varieties of persimmon are distinguished in ‘ astringent’ and ‘ non astringent’. The first ones are the traditional, and the second, the most recent, are the ones consumed nowadays. The kaki includes three different species of the genus Dyospiros, that are distinguished by their size and taste.
The Chinese persimmon (D. kaki) is the most cultivated variety and it is consumed raw as fresh fruit and also cooked in many different ways. The fruit has a diameter of 3-9cm and a weight ranging from 80 to 250g, according to the variety. It is red, orange or yellow, with an orange, sweet and juicy pulp, although with a slightly sharp taste.
The Japanese persimmon (D. Lotus) is similar to the previous species and it is mainly cultivated in the Far East and Italy.
The American Kaki or persimmon of Virginia (D. virginiana) measures 2-5cm of diameter and it is yellow or orange. It is scarcely cultivated and therefore it is harvested from wild trees.
Regarding the varieties, they are classified according to the astringency in ‘astringent’ and ‘non-astringent’. The former is the traditional one, and some of the varieties are ‘Hachiya’, ‘Tanenashi’, ‘Rojo de Carlet’ and ‘Formatero’. Within the second group, that are the mainly consumed at present, we find ‘Sharon’ and ‘Fuyu’. This variety is eaten as an apple. Regardless of the genetic astringency characteristics of the different varieties, the astringency may be controlled to a certain extent with postharvest techniques. Another type of classification is according to the hardness of the pulp. Kakis are collected completely ripe, their pulp is soft and smooth, at the extent that a spoon is needed to eat them. The rest have a harder pulp, and because of their firm texture we must eat them with fork; they can also be peeled quite easily. The hardness and astringency of the fruit are related in some of the varieties; the so-considered non-astringent varieties maintain the hardness of the pulp when the astringency has lowered, and they are even consumed in bites, as if they were apples.
In Spain, the most consumed variety is Rojo Brillante, produced in the region of Ribera del Xúquer, in the province of Valencia. This variety is distinguished by its quality, size, colour, taste and the lack of seeds. It is eaten in two different ways: ‘ Classic’ is harvested ripe, its soft pulp is eaten with spoon; ‘Persimon’ is of a somewhat orange colour and its firmer texture makes it suitable to be eaten with knife and fork. Consell Regulador de la D.O. Kaki Ribera del Xúquer, ( kakifruit.com )
There exist two types of kaki cultivated: Dyospiros kaki and Dyospiros Lotus, that is used as pattern. This tree may reach 18m of height, although when it is cultivated it is left to grow only 5-6m. It is scarcely branched and the habit is more or less pyramidal, although with time it turns into a globose tree. Another type of persimmon of which we eat the fruits is Dyospiros virginiana, although it is not frequently cultivated and it is usually eaten from wild trees. The leaves are of a colour that ranges from green to orange red. They are deciduous, oval and they are slightly hairy in the lower surface. The persimmon has a peculiar reproduction system. Some trees bear masculine and feminine flowers, some others bear only one type of flowers (masculine or feminine), whereas the rest bear hermaphrodite flowers. The flowers are generally arranged in groups of three. The feminine flowers are large, of greenish petals, and arranged individually. At present only the feminine trees are cultivated.
Origin and Production
Persimmons are native to three areas, China, Japan and the United States, depending on the species. The Chinese variety spread all over Asia, from where it was introduced to the rest of the world. At the moment, almost the whole of the production of persimmons takes place in Asia, mainly in China, Korea and Japan. The Chinese variety arrived at Japan in the VIIIth century, where it became a highly appreciated fruit. From there it spread to the rest of the world, arriving at the United States in 1870. In Europe, the American kakis were the first to be introduced. Asia produces 96% of the world-wide production. In Europe and South America there is little production, whereas in Oceania and North America they are hardly cultivated, as it is shown in the following table.
Source: FAO Production Yearbook, 2000
The main producing country, with great difference, is China. The rest are also Asian, Korea and Japan. The following table shows the main producers of this fruit in the world.
Source: FAO Production Yearbook, 2000
The following table shows the main export countries. The amount of produce exported by Israel is outstanding, being the main exporter, compared with Japan, Brazil and China; however, Israel produces much less than these other countries.
Source: FAO Trade Yearbook, 2000
The persimmon is a delicate fruit that is usually commercialised in the producing areas.
It is a fruit in season, that is only available during few months. For instance, in the United Kingdom market it is consumed from February to May. In this case, the produce comes from Chile. However, it is a very delicate fruit, so it is not usual to sell it outside the producing areas.
Kakis are distributed in wood or cardboard boxes with alveoli containing between 2 and 6 units, or in baskets covered in transparent plastic with holes, so as to enable air circulation.
Persimmons must be bought with suitable colouring, without greenish colours. The fruit must be intact, with the calyx.
The fruit must be of yellow to orange colour, according to the varieties. The size also determines the quality of the produce; the larger fruit is better. It must be free of cracks, mechanical damages and rotting. The percentage of soluble solids must be of 21-23% for the variety ‘Hachiya’ and of 18-20% for the variety ‘Fuyu’ and similar non-astringent varieties. There is no specific European standard for kakis, although there is a generic one for fruit and vegetables.
Postharvest Atmosphere Management
Persimmons must be stored at temperatures around 0ºC. Below 2ºC the fruit freezes. The levels of moisture must be kept high, between 90 and 95%. Ethylene is used to eliminate astringency, but it produces an excessive softening of the produce, complicating their marketing. If the air is enriched with 80% of carbon dioxide for 24 hours at 20ºC, we remove the astringency while the firmness is maintained. Kakis have a positive response to controlled atmosphere. The suitable conditions to use it are 3-5% of oxygen levels, levels of 5-8% of carbon dioxide and an atmosphere free of ethylene. Under these conditions and with optimum temperatures and levels of moisture, kakis may last up to 3 or 5 months.
Persimmons are very fragile fruit, so their transport must be extremely careful. The temperature must be as low as possible and the ventilation must be such as to reduce the levels of ethylene. The loads must not be a mix of substances that produce this gas. During distribution, the temperature and ventilation must also be taken into account.
Among the problems that persimmons may undergo during their storage there are damages caused by ethylene, chilling injuries and damages caused by low levels of oxygen and high levels of carbon dioxide.
Damages caused by ethylene: if the concentration of this gas is high, it causes a premature aging of the fruit, leading to the softening and loss of quality.
Chilling injuries: the non-astringent varieties such as ‘Fuyu’ are very sensitive to temperatures between 5 and 15ºC, and they may show browning and softening of the pulp. These problems worsen with ethylene.
If persimmons are subject to environment with levels of oxygen below 3% for more than a month, they may have problems in maturation and loss of taste.
Levels of carbon dioxide over 10% for more than a month may cause pulp browning and taste loss.
|Kaki, Diospyros kaki / Fam.: Ebenaceae|
| Note: Composition for 100 g. of fresh product|
Values in ( min. – max. ) format.
Health Benefits of Persimmon
From a nutritional point of view, persimmons supply 70 kcal/100 g, that come mainly from carbohydrates, although they also provide 10 mg/100 g of vitamin C (around one sixth of the recommended daily consumption) and some carotenoids. Vitamin C may have an influence in some physiological states, such as the suppression of nitrosamine formation in the intestine. Nitrite, which is found in foodstuffs and water, reacts with amines in order to produce nitrosamines, whose carcinogenic characteristics have been tested. The antioxidant capacity of vitamin C can also protect from cancer, intensifying the immunological functions. The diets that are rich in carotenoids have been related to a decrease of the risk of contracting cancer and cardiovascular diseases.
Different parts of the persimmon are used for medicinal purposes: the fruit, the leaves, the tree bark or even the flowers. It lowers the blood pressure, it relieves cough and prevents arteriosclerosis, among many other properties. When it is unripe, it contains a great amount of iodine, that helps to relieve goitre. In the last few years it has been stated that kaki’s leaves are good to lower the pressure, prevent arteriosclerosis, purify the blood and lubricate the intestine. Besides, the persimmon is a tranquillizer, it stimulates the corporal fluids and calms the thirst. It fortifies the spleen, it fights diarrhoea, blood in faeces and haemorrhoids. The flowers are used to treat measles, whereas the bark of the tree is used to cure burns. Kakis are suitable for weak and depressed people, thanks to their content in vitamins of group B.
Nutrition and Eating
Different parts of the persimmon are used for medicinal purposes: the fruit, the leaves, the tree bark or even the flowers. It lowers the blood pressure, it relieves cough and prevents arteriosclerosis, among many other properties.