Agriculture Reference
In-Depth Information
loose panicles. The enlarged juicy peduncle that bears the nut is known as the “cashew apple.” When
ripe, it is of a golden-yellow color and obovate in shape; it has a pleasant, acid flavor and is somewhat
astringent. The cashew nut hangs from the end of the cashew apple and is kidney shaped and about
2.5 cm long. It consists of an edible kernel surrounded by two shells. The outer shell is smooth and of
a bright brown color. Between the two shells, there is a very caustic oily substance. The cashew kernel
is considered to be of high nutritive quality and is covered with a thin reddish-brown skin or testa.
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Habitat and Distribution —
The cashew tree was originally native to Brazil and was later
introduced by the Portuguese to Mozambique and then India in the sixteenth century as a means
of controlling coastal erosion. It was not until the nineteenth century that plantations were devel-
oped, and the tree then spread to a number of other countries in Africa, Asia, and Latin America.
The cashew is now distributed throughout the tropics and in parts of the warm subtropics. Cashew
processing, using manual techniques, began in India in the first half of the twentieth century, when
cashews were exported to the wealthy Western markets, particularly the United States.
Ethnomedicinal Uses —
All parts of the tree are used in traditional medicine. Cashew leaves
are used extensively in traditional medicine for the treatment of fevers, skin disease, diabetes, and
hypertension. The fresh juice from the fruit is effective for the treatment of syphilis, cholera, and kid-
ney disease and is antiscorbutic, astringent, and diuretic. Root infusion is an excellent purgative. The
stem bark is astringent, counterirritating, rubefacient, and vesicant and is used for ulcers. Cashew
nut shell oil is antihypertensive and purgative; it is used for blood sugar problems, kidney diseases,
cholera, cracks on the soles of feet, hookworms, corns, and warts. The kernel is a demulcent and an
emollient and is used for diarrhea. The resinous juice of seeds is used for mental derangement, heart
palpitation, and rheumatism. A gum exudes from the trunk and repels insects. An extract of the peri-
carp and nut is used to treat wood to give complete protection against beetles. Cashew syrup is a good
remedy for coughs and colds. Cashew apple juice is said to be effective for the treatment of syphilis.
Constituents —
Cashew elaborates a complex mixture of compounds in different parts of the
plant. The kernel testa (skin) is reported to contain huge amounts of tannin, and the tannin extracted
from cashew kernel testa is used in the leather industry. The juice of the cashew apple is rich in
riboflavin (vitamin B
2
), ascorbic acid (vitamin C), and calcium. The nutrient composition of the
cashew fruit apple is as follows:
Composition of Cashew apples
Moisture
86.1 (g/100 g)
Proteins
0.8 (g/100 g)
fat
0.2 (g/100 g)
Carbohydrate
12.6 (g/100 g)
fiber
0.6 (g/100 g)
ash
0.3 (g/100 g)
Ca
0.2 (mg/100 g)
P
19.0 (mg/100 g)
fe
0.4 (mg/100 g)
Vitamin b
1
0.2 (thiamine mg/100 g)
Vitamin b
2
0.2 (riboflavin mg/100 g)
niacin
0.5 (mg/100 g)
Vitamin C
200 (mg/100 g)
The seed contains 21% protein and 35-45% oil. The oil contains 60-74% oleic acid and 20-8%
linoleic acid. Cashew nut shell liquid (CNSL) contains 90% anacardic acid (C
22
H
32
O
3
) and 10%
cardol (C
32
H
27
O
4
). It also yields glycerides; linoleic, palmitic, stearic, and lignoceric acids; and
sitosterol. Other constituents include anarcardol, cardanol, quercetin, and kaempferol glycosides.
The presence of the phenolic lipids related to anacardic acid in cashew is of immense industrial and
