Loquat – Health Benefits of Loquat

Revisado por Equipe Editorial a 13 janeiro 2018

The loquat is a rounded fruit of orange colour that is appreciated for its aromatic, sweet and somewhat acid flesh. It is usually eaten raw, although they are also processed to prepare jams, pies or juices. It barely provides the organism with nutrients, although it contains potassium in a significant quantity and some vitamins. There are two species of loquat, the European and the Japanese, although the most well-known is the latter. It is a rounded or pear-shaped fruit, with a thin and hard skin, of a yellow-orange colour. The pulp is aromatic, of white or orange colour, fleshy and of sweet, somewhat acid taste. It contains several brown seeds of great size.

Loquat are mainly consumed raw, as fresh fruit. They are also used to process sauce, jellies, jams and confectionery products, along with juices or syrups. In some cases they are stewed; in the Bermuda they make a characteristic liquor. It is low in nutrients and calories, reason why it is recommended in slimming diets. It provides with potassium and small quantities of calcium, phosphorus, magnesium and iron. It also contains small amounts of vitamin B1, B2, B3 and C. 

Types and Varieties of Loquat 

Two groups of varieties are clearly distinguished. On the one hand, the Japanese type (also called Japanese plum), having a smaller amount of seeds and a paler coloration of the fruit, both of the skin and the pulp, and being of early maturation. On the other hand, the Chinese have the opposed characteristics, that is to say, greater number of seeds, later harvesting and darker fruit colour. Among the main cultivated varieties in Spain we find the following ones: 

Tanaka: it is a variety of late maturation with fruits of good size and extraordinary taste. 

Algerie: this variety represents 80% of the production of Alicante; it is also widely cultivated in Almeria, due to its earliness. However, the fruits are of smaller size and worse flavour. 

Other varieties are ‘Magdall’ and ‘ Golden Nuget’ that are worse in taste, but of early maturation. 

The Plant 

The loquat tree measures 5-8m high, it is extremely branched and it blooms in autumn, bearing a great number of white flowers grouped at the tips of the branches. These flowers give rise to a very juicy orange fruit of somewhat acid flavour, 6cm long. The loquat is a plant belonging to the family of Rosaceae, whose scientific name is Eriobotrya japonica. It is a small tree, 5-8m high, with a rounded crown. The trunk is straight and branched at a very low height. The roots are extremely superficial. The leaves are alternate and hairy, of lanceolate or elliptical shape. They measure between 15 and 20cm long and they have sawed edges. The flowers are white and small, 1.5cm of diameter. They bear 5 wide petals. They are grouped in great number at the end of the buds, although not all bear fruit and many of them fall. The fruit has pear-shape and yellow-orange colour, between 2.5 and 6cm of length. The skin is thin and strong and the pulp is white or yellow, juicy and somewhat acid. It contains between 1 and 10 seeds of dark brown colour. This species blooms in autumn, although in the tropical it may undergo up to three flowerings a year, being the second one of greater yield. 

Origin and Production 

The loquat is native to the Far East, where it was used as an ornamental tree in the orchards and gardens. It is thought to come from the south of China, from where it was introduced in Japan. In these two countries there are already quotations on this species during the VIth century. From Japan it was introduced to Europe and Africa; it arrived at the Old Continent in the middle of the XVIIIth century. The United Nations Agriculture and Food Organization (FAO) gathers the production and export data of the loquat, along with some other fruit of scarce economical interest, like carambola, cherimoya, feijoa, guava, mangosteen, passion fruit, rambutan, sapote, etc. The continent with greater production of tropical fruit is Asia, standing for 83% of the total production. Some of it is also cultivated in South America, whereas in the rest of the world there is a scarce production.

Continent    Tons    % 
  Africa    406,270    3 
  Asia    12,736,173    83 
  Europe    25,000    – 
  North America    366,390    2 
  South America    1,766,650    12 
  Oceania    30,826    – 
  Total    15,331,309    100 

Source: FAO Production Yearbook, 2000 *

The countries with larger production of tropical fruit are the Asian: India, the Philippines, Indonesia and China. Some South American countries are also included among the 10 main producers.

  Country    Tons 
  India    3,700,000 
  The Philippines    3,600,000 
  Indonesia    2,000,000 
  China    1,675,192 
  Colombia    1,120,000 
  Thailand    704,000 
  Pakistan    468,500 
  Brazil    335,000 
  Bangladesh    267,000 
  Peru    253,179 

Source: FAO Production Yearbook, 2000 *

The main export country is Malaysia, followed by the United States and Kenya. The following table shows the 10 main exporters of tropical fruit:

  Country    Tons 
  Malaysia    52,412 
  The United States    28,269 
  Kenya    10,592 
  Thailand    5,542 
  Indonesia    4,794 
  Egypt    4,081 
  Madagascar    3,642 
  Yemen    2,953 
  China    2,914 
  Australia    2,897 

Source: FAO Trade Yearbook, 2000 *

* Data referring to several species like carambola, cherimoya, litchi, feijoa, guava, mangosteen, passion fruit, rambutan and sapote. 

Availability 

The loquat is the first stone fruit arriving at the markets in spring. In Israel it matures between the end of February and the end of March. In Spain it does so from March until May, whereas in Japan it is harvested at the beginning of June. It is a season fruit that can only be consumed during these periods, since it is badly preserved. 

The following table contains information on the availability of this fruit in the United Kingdom markets. The months in which each country imports the produce and the weight of the packages used are also indicated.

Country of origin    Availability    Weight of the packages 
  Australia    Sporadically    Various 
  Brazil    Mid April-May    5kg 
  Chile    September-December    Various 
  Cyprus    May-July    3/6kg 
  India    December    2/5kg 
  Israel    April-May    4kg 
  Italy    March-June    Various 
  Spain    April-June    5/6kg 
  Turkey    Sporadically    Various 
  The United States    Sporadically    Various 

Source: Fresh Produce Desk Book (1998) 

Packaging 

The loquat is a very delicate fruit that requires careful handling to avoid damages. Before packaging, the peduncle is cut 0.5-1cm in order to avoid rubbing against other fruits. The packages used must be of small capacity and the bottom of the boxes must have a foam rubber film. Afterwards, they are covered with a thin paper. The boxes may be of cardboard or wood, and palletized for their transport. 

Regulation
The Spanish quality standard for the loquat intended for domestic market is laid down in the Order of 27 November 1987 (B.O.E. of 5 December 1987). This standard states that all the loquats must be marketed intact, with peduncle, sound, clean, free of abnormal external moisture and free of any strange smell or taste. Their condition must be such as to enable them to withstand handling and transport and to arrive in satisfactory condition at their place of destination. This fruit is graded in four classes according to its quality. 

Extra Class: these fruits are those of the best quality. They must be free of any defect and the peduncle must be intact, not exceeding 10mm. 

Class I: slight defects of coloration, shape or development are allowed in this class. 

Class II: in this case the fruits may show slight defects in the peduncle. The pulp may show small injuries; defects of shape, development or coloration are allowed. 

Class III: these loquats are those of the worse quality. The same defects as for Class II are allowed, but of greater intensity, provided the fruit satisfies the minimum quality requirements. The size will be determined by the maximum diameter of the equatorial section of the fruit, according to the following scale:

Diameter in mm    Identification of the size 
  53mm or larger    GGG 
  46mm inclusive to 53mm exclusive    GG 
  39mm inclusive to 46mm exclusive    G 
  32mm inclusive to 39mm exclusive    M 
  25mm inclusive to 32mm exclusive    P 

For the Extra Class and Class I, the minimum size required is 32mm; for the rest, 25mm. Tolerances of size and quality in each package are allowed for fruit not satisfying the characteristics required. In the case of the Extra Class, 5% of the fruit may belong to the immediately inferior class. For Class I and II the percentage is 10%, whereas for Class III it is 15%. Concerning size, 10% of the produce may not satisfy the measurement indicated in the package. The content of each package must be uniform and contain fruit of the same origin, variety, class, stage of maturity and size. They must be correctly prepared, using new and clean material, free of any substance that may damage the produce. The maximum capacity of the packages is 10kg of net content, except for Class III, in which case the packages may contain 15kg of produce. The fruit is also displayed in small packages; in a single bed, each fruit isolated from the rest; fitted in or in bulk. Each package must clearly bear the name of the variety, the class, size and origin of the produce. 

Quality Criteria 

Postharvest Atmosphere Management 

The loquat is stored, at the most, for 2-4 weeks, depending on the variety and the degree of maturation. The optimal conditions of storage are temperatures of 0ºC and relative humidity between 90 and 95%. If they are packaged with perforated plastic films the loss of water is reduced, improving preservation. If they are put in contact with ethylene, it will cause the acceleration of green colour loss, although the taste of the fruit will not improve. 

Postharvest Problems
The physiological alterations that loquat may undergo during storage are flesh browning and ‘russeting’. They are also affected by diverse fungi, causing rots like Botrytis cinerea, Colletotrichum gloeosporioides, Pestalotiopsis funerea and Phytopthora cactoarum. 

Internal browning: this alteration is characterized by a darkening of the flesh, followed by the tissues decay. This phenomenon is favoured by high temperatures and long storage. It is also caused by high concentrations of carbon dioxide. 

‘Russeting’: consisting of brown-coloured spots in the skin, that diminish their commercial value. It occurs in the field, and it depends on the variety, the season and the climatic conditions. Among the most important diseases occurring during storage are the fungi Botrytis cinerea, Colletotrichum gloeosporioides, Pestalotiopsis funerea and Phytopthora cactoarum, specially in rainy areas. These pathogens cause various rots that affect the fruit. The strategies to control them include careful handling so as to avoid damages in the fruit, fast cooling and optimal storage conditions. 

Healthy Effects

Loquat, Eriobotrya japonica / Fam.: Rosaceae
 Note: Composition for 100 g. of fresh product
           Values in ( min. – max. ) format. 
Energy: 28-54 kcal
Fats: 0.2-1.0 g
Fibres: 0.30-2.07 gMinerals Calcium: 16-20 mg
Zinc: 0.2-0.2 mg
Phosporus: 11-23 mg
Iron: 0.3-0.4 mg
Magnesium: 10-10 mg
Manganese: 0.1-0.1 mg
Potasium: 220-263 mg
Selenium: 0.5-1.0 µg
Sodium: 1-4 mg
Proteins: 0.4-0.7 g
Carbohidrates: 6.3-10.5 gLiposoluble Vitamins A Retinol: 133.3-133.3 µg
A Carotenoids: 160-800 µgHydrosoluble Vitamins

B1 or Thiamine: 0.020-0.045 mg
B2 or Riboflavine: 0.030-0.061 mg
B3 or Niacine: 0.2-0.4 mg
C or Ascorbic Acid: 1-4 mg

Health Benefits of Loquat
The loquat supplies the organism with few calories, since it hardly contains lipids nor proteins. Among the minerals supplied stand out the potassium, calcium, phosphorus, magnesium and iron. It barely contains sodium. Among the vitamins, the chief ones are B1, B2, B3 and C. The nutritious value of this fruit is quite low. It hardly contains lipids nor proteins, and its carbohydrate contribution (mainly fructose and glucose) is moderate. For all those reasons, its caloric content is low and thus it can be consumed without any problem by people who follow slimming diets. The mineral contribution comes mainly from potassium and the scarce amount of sodium. Potassium is very important for the cellular metabolism and the lack of it in the organism leads to muscular weakness, mental disorder and upheavals in the heart functioning. Moreover, it provides with calcium, phosphorus, magnesium and iron. Its vitamin content is quite low, although it supplies with small amounts of vitamin B1, B2, B3 and C. The latter protects the cells from oxidation and improves the absorption of iron. Some varieties of this fruit contain carotenoids, the precursors of vitamin A. The loquat contains pectins and organic acids like the acetic, citric, malic, tartaric and formic acids. 

Popular Tradition
The loquat is a digestive, diuretic and depurative food. Furthermore, it reduces the levels of cholesterol and it is recommended to people suffering from hypertension. The leaves are used in some countries to cure various diseases like diabetes or cough. The loquat is a very digestive fruit, recommended to people with delicate stomach. It has diuretic properties and it is appropriate for people suffering from high blood pressure, since it is rich in potassium and low in sodium. Moreover, it is a depurative fruit. If it is consumed in juice or syrup, it may cure diarrhoeas, thanks to its astringent properties. Its pectin content reduces the levels of cholesterol. The leaves are used in several countries to treat skin diseases and diabetes. The Chinese traditional medicine recommends products containing the loquat leaves’ extract and other plants in order to cure chronic bronchitis, cough and pulmonary congestion. 

Nutrition and Eating
The loquat is a digestive, diuretic and depurative food. Furthermore, it reduces the levels of cholesterol and it is recommended to people suffering from hypertension. The leaves are used in some countries to cure various diseases like diabetes or cough.