The pulasan (scientific name Nephelium mutabile) belongs to the plant family Sapindaceae. This is a tropical plant whose fruit is closely related to rambutan. As a result, often people mistake the pulasan fruit for that of rambutan. Generally, the pulasan fruit is consumed fresh. This fruit tastes sweeter compared to the rambutan and lychee. However, you will rarely find pulasan fruits outside Southeast Asia.
The plant derives its name “pulasan” from the Malay term “pulas” denoting twist, which is related to the Tagalog word “pilas” meaning remove. This refers to the fact that the pulasan fruit is opened by twisting it using both hands. Hence, it has been perfectly named pulasan.
The pulasan is an ornamental tree, which grows up to a height of anything between 10 meters and 15 meters. The trunk of this tree is quite short having a thickness of 30 cm to 40 cm. When the tree is young, its branchlets are brown as well as hairy. The leaves appear alternately, are pinnate or oddly pinnate and measure up to anything between 17 cm and 45 cm in length. Each leaf has two to five pairs of leaflets that are arranged opposite or almost to each other. The leaflets are elliptic-lanceolate or oblong, measuring 6.25 cm to 17.5 cm in length and about 5 cm in width. The somewhat wavy leaves have a deep green and glossy hue on the top surface, while they are pale and slightly bluish on the underside having a few small, silky hairs. The flowers of the pulasan are very small and without petals. They just comprise four to five sepals, which may appear solitarily or in clusters on the erect terminal or axillary branches. The panicles are covered with delicate hairs of yellow or brown hue.
The deep red pulasan fruit has an ovoid shape and measures anything between 5 cm and 7.5 cm in length. The leathery rind of the fruit is thick and closely attached to the blunt-tipped tubercles or substantially fleshy spines that are straight and measure about 1 cm in length. In some cases you may also find a couple of small, not fully formed fruits cuddle up near the stem. Inside of the fruit is a white or yellowish-white glistening flesh (also known as aril). The flesh is about 1 cm thick and somewhat attached to the greyish-brown, slender seed coat. The seed coat or testa actually separates the fruit’s flesh from the seeds. Generally, the pulasan is sweeter compared to the rambutan. The shape of the light brown seeds may vary from ovoid to ellipsoid to oblong. To some extent, these seeds are flattened on any one side and measure between 2 cm and 3.5 cm in length.
Although the pulasan has a very close relation with rambutan, this fruit does not have any hairy spine like the latter. Moreover, the flesh of the pulasan is very sweet, sweeter than rambutan, and succulent. Compared to rambutan, the flesh of this fruit can be separated from the seeds very easily. Even the seeds of the pulasan are different from that of rambutan. The seeds of the pulasan are also edible raw and their flavour is akin to the almonds.
The pulasan tree has its origin in Southeast Asia, especially the Peninsular Malaysia. These trees are found growing in the wild in fewer numbers in the lowland forests in the region of Malaysia’s Perak region. On the other hand, they are found in abundance even at low altitudes in the Philippines – ranging from Luzon to Mindanao. Since long, this tropical tree has been cultivated by people in Thailand and the Malay Peninsula. However, it is seldom cultivated in the Philippines.
In 1926, the pulasan tree was first planted in Puerto Rico’s Trujillo Plant Propagation Station. In 1927, young trees of this species were dispatched from Java to the Lancetilla Experimental Garden, Tela in Honduras. It is said that the trees sent to Tela were doing well in 1945 and bearing moderate amount of fruits. Apart from Costa Rica, people in other regions of the New World hardly know about the pulasan. However, the tree is cultivated sporadically in Costa Rica and its fruits are sometimes seen being sold in the local markets.
Fruits, roots, leaves.
The fruit of the pulasan contains high levels of antioxidants. Its antioxidant action is attributed to the elevated levels of vitamin C. The antioxidant properties of this fruit are augmented owing to the presence of other chemicals like vitamin C, hydroquinone and pyrogallol. This fruit also contains carotenoids and vitamin E, which contribute to the pulasan fruit’s ability to scavenge free radicals.
The pulasan fruit is useful for making the skin softer. In addition, this fruit also forms an ingredient in several hair care products. A study has confirmed that a smoothie made from carrots as well as some specific Malaysian fruits that are underutilized like pulasan can help to make the complexion better. Aside from making the skin glow, it offers other health benefits too. The oil extracted from the dried out seeds and kernel of the pulasan contain nearly 75 percent white fats. These fats not only have a pleasantly mild fragrance, but are also excellent for the health of our hair.
Pulasan also lessens body fat effectively. Hence, this fruit is beneficial for obese people. In fact, it is recommended that people with diabetes should consume this fruit regularly. Even the leaves and roots of this tree are used for therapeutic purposes, especially in poultices. A decoction prepared from the pulasan root is used in the form of a vermifuge and febrifuge. In addition, these roots are also boiled along with Gleichenia linearis. The resultant decoction is employed for patients with fever.
Even the light red wood of the pulasan has a number of uses. Although this wood is available rarely, it is of excellent quality. Compared to the wood of rambutan, this wood is harder as well as heavier.
The somewhat succulent flesh of ripened pulasan fruit is consumed raw. Alternatively, the ripe fruits of this tree are also used for making jam. The seeds of this plant are boiled or roasted and subsequently used to prepare a beverage similar to cocoa.
You eat the ripe pulasan fruit in the same way as you would eat the rambutan. You simply need using both your thumbs to press the fruit to open up. The skin of this fruit is leathery, but soft. However, it is relatively thicker compared to the rambutan and tearing the skin apart is somewhat harder. Once you open the fruit after tearing its somewhat thick skin, just pop its white, semi-transparent fleshy tissue into your mouth. Alternatively, you may also simply crunch into the fruit from your hand.
The pulasan fruit is somewhat juicy and tastes sweet. You can eat the ripe fruit raw from your hand. Even the seeds of this fruit are edible and they have a flavour similar to that of almond. Aside from consuming the fruit raw, you can also dry out or store it in a freezer and later use it to add flavour to puddings and ice cream. You can also use the fruit to make jams, jellies, sauces and preserves. Moreover, gourmet restaurants have also been using the ripe pulasan fruit in their main course dishes, in addition to adding it to sauces. In recent times, the ripened pulasan fruit has been utilized in a number of tropical juice mixes. The flesh of this fruit tastes akin to grapes and is often used for making jams.
Habitat and cultivation
The pulasan (Nephelium mutabile) is an exclusively tropical plant and it only prospers in extremely humid areas located in altitudes between 360 feet and 1,150 feet. People in Malaya believe that this tree bears the best and most delectable fruits following a prolonged dry season.
While not much is known regarding the type of soil that is best for cultivating the pulasan, it is generally agreed that this tree thrives in conditions that are humid all the time.
It is not advisable to propagate the pulasan from its seeds, as the seedling may either be a male or a female. Like in the case of rambutan, plants propagated via air-layers do not survive for long. However, budding may prove to be successful for propagating the pulasan provided it is done during the rainy season. Budding should be done on rootstocks that are already established in the field, as they will not require transplanting. In fact, many young pulasan plants are unable to bear the trouble of transplantation and die during the process. This is more common when the weather conditions are arid.
Chemical analysis of the pulasan fruit has revealed that it encloses several valuable nutrients, including carbohydrates, proteins, some amount of fat, calcium and even iron. In addition, this fruit contains significant amounts of vitamin C.
It has also been found that the pulasan fruit contains other chemicals including hydroquinone compounds and pyrogallol. These compounds are said to be responsible for the potent antioxidant property of the pulasan fruit. Similarly, carotenoids and vitamin E present in the pulasan fruit are capable of scavenging the harmful free radicals.