Agriculture Reference
In-Depth Information
(papaya, avocado) and endocarp (citrus). A few species are in the magnoliid
complex (annonas, avocado) and monocots (banana, coconut, pineapple);
the most important species are all eudicots. The fl oral parts of the magnoliid
complex occur in whorls of three (trimerous); the pollen has one pore and
they usually have branching-veined leaves and are regarded as basal or more
'primitive' angiosperms.
Tropical fruits, in most cases, are sold fresh, and of -grade fruit is
processed. The exception to this would be coconut, which is grown principally
for other products (copra, oil, coir) with a small acreage, often of special
varieties, that are grown for fresh consumption. Cashew is grown mainly
for its nut, with the fl eshy pedicel being eaten fresh, processed and made into
juice. Most tropical fruits are highly perishable, and signifi cant development
has taken place to process selected fruits into dried products, juices and purees.
Bananas such as plantains are also often used as a starch staple in Africa, Asia
and Latin America and not as a dessert fruit.
NUTRITIONAL VALUE
Nutrient contents of tropical fruits found in food composition tables are used
for nutritional assessment, research linking diet to health, nutritional policy,
food labelling, and consumer education. Accurate data are needed in order to
predict dietary energy intake and undernourishment. For tropical fruit, this
is important, as they are often regarded as signifi cant sources of minerals,
vitamins and carbohydrates (Favier
et al.
, 1993).
Natural variation occurs in the nutrient content of fruits. This variability
is due to soil and climatic conditions, variety grown, the stage of maturity at
harvest and physiological state when eaten. Traditionally, food composition
tables for most foods are presented as mean values, ignoring the natural
biological variability. It is probably more useful to know the range of values
found and the standard error or deviation.
Most food composition tables present data as nutrient values per 100 g of
edible food. Tropical fruits have low to moderate energy content and provide
about 200 to 300 kJ (FAO, 2003). Some tropical fruits, such as bananas (380
kJ), avocado (572 kJ) and durians (536 kJ), are higher and others less energy-
dense, such as the carambola (121 kJ). The protein content of most fruits,
including tropical fruits, is low (<1 g/100 g), though avocado (1.8 g) and
durians (2.6 g) are higher. Fat contents are also low, except for avocado (14.2 g)
and durians (2-5 g). The carbohydrate content is presented as monosaccharide
equivalents with fi bre excluded, and contents normally range from 10 to 15 g,
which is the range that most consumers regard as sweet. Higher carbohydrate
contents are found in bananas (~20 g), atemoya (~21 g) and durians (~26 g).
Dietary fi bre is reported to range from 1 to 2 g in tropical fruits, though dif erent
analytical methods are used that give dif erent values in the same fruit.
