Tamarind monograph.pdf - Crops for the Future

Chapter 9. Harvest, Postharvest and
Processing
9.1 Introduction
K.V.R. Ramana, B.A. Prasad and P. Vijayanand
Harvesting of tamarind fruits commences when the pods feel brittle by
pressing. Trees grown from seed may take more than seven years to start
bearing and up to 10 or 12 years before an appreciable crop is produced.
Unselected trees in India are late bearers and may take 10-14 years before
fruiting. Well-tended trees grown in open areas will come into bearing early,
in about seven years or less. Grafted trees will however come into bearing
several years earlier. It is reported that in Madagascar trees will begin to
bear in the fourth year and in Mexico in the fifth year. The sweet cultivars
planted in Thailand bear in about 3-4 years. These differences in the onset of
bearing may be associated with genetic or ecological factors. According to
Coronel (1991), plantations in the central delta of Thailand become dwarfed
due to the high water table, which prevents the growth of a deep root system.
Such stress conditions lead to early bearing. In all cases, pod yield stabilises
at about 15 years and continues for up to 50 or 60 years.
Tamarind seed pods fill at maturity. The pulp becomes brown to reddish
brown and the testa becomes brittle and cracks easily. The pulp dehydrates
and becomes sticky and the seeds become hard, dark brown and glossy.
Mature fruits have brown shells, while immature ones are green. Tapping
them with the finger can help to identify the mature fruits. A hollow, loose
sound will be produced as the pulp shrinks with maturity and the shell
becomes brittle. At this stage the fruits are mature and ready for harvesting.
However, it is not always easy to determine whether the fruits are ready for
harvesting, as the testa colour only changes slowly as the pods mature.
Individual fruits on the same tree also mature at different times making it
necessary for the harvesting to be done selectively.
The pods are gathered when ripe and the hard pod shell is removed. The
pulp is preserved by placing it in casks and covering it with boiling syrup or
packing it carefully in stone jars with alternate layers of sugar. The seeds,
when used as a food, are roasted and soaked in water until the hard seed coat
splits and comes off. The cotyledons are then boiled and eaten.
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