Thanks to the convenience of air transportation and the active exchange of commodities globally. Durian, an exotic fruit that most Americans are not familiar with, can be found in most Asian supermarkets across the USA. This fruit is extraordinarily unique, known as the king of the fruits in Southern Asia, but also brings two extremely controversial responses, people either love or hate it. The taste of durian is a complex experience that has been described as something like a concoction of ice cream, onions, spices, and bananas all mixed together. It has a pleasant creamy consistency, a pronounced sweet taste, with a strong and penetrating odor that is not comparable to any other kind of fruit. The aroma of ripe durian is so unique that comes from volatile compounds like sulfur and complex ester.
There are many varieties of durian fruits. More than three hundred varieties in Thailand with the most famous varieties of Chanee and Monthong which can be purchased in the USA. There are about twelve popular varieties in Malaysia, each variety differs in taste in terms of fragrance, texture (buttery, sticky, creamy, and soft), and sweetness (mildly sweet, sweet, and bitter). The differences between varieties were given rise by the differences in the geographical locations in the aspect of weather and soil conditions. Among all, Durio zibethinus L. var. Mao Shan Wang is the most expensive one which is also known as Musang King. It is easily differentiated from the rest as it has a “star shape” opening at the bottom.
Scientifically known as Durio zibethinus L. Durian is a spiky tropical fruit tree in the family of Bombacaceae with the order of Malvales. Plants from this family are best known for their showy flowers as well as woody or thin-shelled pods filled with small seeds and silky or cotton-like fiber. There are about 51 genera within this family and the genus Durio has approximately 28 species. Durian is the member that differs radically as compared to other genera for their large seeds surrounded by fleshy arils. Apart from the common name, durian is also known as civet cat tree and civet fruit in India as well as “stinkvrucht” in Dutch notably for their strong and notorious odor. It is a famous and popular native fruit in Southeast Asia. Specifically, it is widely cultivated in Thailand, the Malay Peninsula, Malaysia, Indonesia, and the island of Borneo. Durian is not grown in the mainland of the USA but in the island territories such as Hawaii and Puerto Rico. Most fresh durians in the mainland are from Hawaii.
As a tropical plant, Durian is not happy in the areas where the temperature falls below 65 degrees Fahrenheit (18 degrees Celsius). They prefer moist, humus-rich soil with full sun or dappled shade. The tree reaching 90 to 130 feet (27 to 40 meters) in height in the wild tropical forests. The tree has an irregular dense or open crown of rough branches. The branch is usually a short, straight, rough, peeling trunk with a diameter up to 4 feet (120 centimeters). Each branch is branched out into thin branchlets coated with coppery or gray scales before maturation. They have elliptical, dull green, and scaly leaves. The leaves are evergreen about 8 inches (20 centimeters) long, dark green showed on the upper surface and paler on the undersides. The leaves are alternately arranged with oblong-lanceolate or elliptic-obovate that rounded at the base and abruptly pointed at the apex.
Flowers: Durian has a complete or perfect flower that has stamen and pistil. Their flowers can be creamy white, greenish-white, or pink with a heavy scent and found in a cluster of 3 to 30 that grow directly on the trunk and branches. They are climatic fruit trees because they bloom twice a year when there are no or few drops of rain throughout the blooming season. The flowers are very fragile to raining as the raindrops will “break” the flower stalk thus result in no fruit will be produced. Therefore, durian is seasonal and only produced in April and May as well as June to July.
Fruits: as the products of pollination from the flowers, Durian is notable for its high sugar content. Generally, the durian fruits are large, spiny, green to yellow in color. The fruit is ovoid or void-oblong to nearly round (depends on the varieties) which can be 6 – 12 inches (15 to 30 centimeter) long, 5 – 6 inches (12.5 to 15 centimeter) wide, and up to 15 pounds (8 kilograms) in weight. The color of the thick, tough, semi-woody rind that is densely set with stout and sharply pointed spines can be yellow or yellowish-green. Interestingly, it has three- to seven-sided at the base. They are about five compartments or chambers containing the creamy-white, yellowish, pinkish, orange, or red color flesh. Durians are very nutritious with high levels of vitamins, minerals, antioxidants such as caffeic acid and quercetin, various fatty acids, and high content of carbohydrates as well as carotenoids.
Another amazing trait is that the fruit will expand the opening at the bottom of the fruit when still hanging on the tree reaching its maturation. This mechanism is known as dehiscence, which is their strategy to attract animals such as monkeys and squirrels for seed dispersal. When it starts to break open, the strong fragrance that released into the air will attract animals to eat it. A widespread saying in the orchard is that the durian bitten by a squirrel is the best as their nose is highly sensitive in detecting the most delicious durian. However, not many people dare to eat a “leftover”, saving the best for animal friends. The fruits are dropped to the ground by gravitational force eventually which is an open invitation for all animals to share. Dehiscent durian fruit cannot be kept for long periods of time, especially in warm conditions. This is because the aril or pulp is easily infected by microorganisms, insects, as well as losing in taste by oxidized tissue. It’s a great idea to harvest Durian before reaching the stage of maturation. The fruits continue to undergo physiological and biochemical changes during ripening such as respiration, ethylene production, softening as well as color development which is essential for an excellent taste. The color of the durian pulp will change from white or whitish-yellow to yellow, orange, or red depends on the varieties.
Propagation: It can be propagated from seeds as durian has a high degree of self-incompatibility and the pollinations are mainly done by the honeybees and bats. However, due to the genetic variations, seeds lose viability very quickly, the best fruiting cultivars are grafted or budded. Neither air-layering nor cutting will root satisfactorily therefore it is often propagated through grafting. Selected cultivars are propagated by patch-budding onto two months old and pencil-thick rootstocks. The grafted trees will never grow as tall as seedlings which usually ranged between 26 – 32 feet (8 to 10 meters) tall. Young grafted plants require dedicated horticultural practices that they should be staked and irrigated daily in the dry season and receive a sufficient amount of fertilizer.
For those who are ready to try this unique exotic fruit. Here are some cautions to take. Based on ancient Chinese Daoism philosophy, it’s important to stay balanced between Yin and Yang which is a universal concept. Foods that are grouped as giving “heat” to the body such as Durian should be consumed cautiously to avoid internal unbalancing which may result in tissue inflammation. The list of foods and drinks that should be avoided including alcohol, milk, coffee, beef, crab, or fruits with high sugar content such as mangosteen and lychee. People with preconditions should aware of some of the consequences that may lead to severe indigestion, increases blood pressure, and heartburn. It’s always recommended to start with a small piece to test the acceptance level.
Further readings:
Morton, J. F. (1987). Fruits of warm climates. JF Morton.
Rodrigues, S., de Oliveira Silva, E., & de Brito, E. S. (Eds.). (2018). Exotic Fruits Reference Guide. Academic Press.
