Proximate Composition and Mineral Contents of Duku ( Lansium domesticum ) Fruit

A native fruit of Southeast Asia, duku (Lansium domesticum) fruit is grown in Malaysia, notably in the state of Terengganu, renowned for its premium quality. Physically, the fruit is signified by thick fairly leathery golden brown skin, shaped oval or almost circular whose short diameter range between 40 – 50 mm. Organoleptic attributes of the fruit are derived from the sweet-sour aromatic profile elicited from the juicy flesh. Recognition of fruits constituting healthy diets is a cornerstone for ascending global consumption trends. In this respect, this study of various components of duku fruit harvested in Terengganu aimed to evaluate the nutritional constituents as source of potent health promoting chemicals, and identify correlations between experimental variables. Proximate composition and mineral content analysis were based on the standard procedures of AOAC (2011). Crude fat, crude protein and carbohydrate content enabled mathematical derivation of caloric value. Inductive couple plasma optical emission spectrometry (ICP-OES) facilitated mineral content analysis. Comparatively, duku peel had highest ash value, 1.2 g per 100 g, whereas duku flesh lowest, containing 0.4 g per 100 g, WB. Crude protein results proved seeds were highest, 3.0 g per 100g, in contrast to flesh at 0.9 g per 100 g. Crude fat were found in peel and seeds, 2.7 g and 0.1 g per 100 each, respectively but not detectable in flesh. Crude fibre tended to be significantly higher by 10 fold in seeds compared to flesh, evidently at 5.2 g in the former while 0.4 g in the latter based on 100 g sample weight each. Mineral elements analysis, specifically of potassium, calcium, and magnesium revealed superior valuations in peel recording 2692.9 mg, 361.5 mg and 144.1 mg respectively, on a 100 g sample weight basis. Relatively lowest were results obtained from flesh at 762.5 mg, 73.0 mg and 43.8 mg respectively, based on 100 g sample weight each. The spectrum of values attained from the variables researched points to future potential of duku fruit commercialization as a potent ingredient in food and beverage products. Nevertheless, related complementary research to augment this current work is required before the wholesome intrinsic qualities of this fruit can be realistically capitalized.