Tamarind monograph.pdf - Crops for the Future

In most of the tamarind growing countries pulp is pressed and preserved in
large masses and sold in small shops and markets by weight. Sometimes the
cleaned pulp is compressed and packed in palm leaf mats or gunny bags for
storage and marketing. In East India, the pulp is covered with salt, rolled into
balls, exposed to dew and stored in earthenware jars (Chapman, 1984;
Morton, 1987), whereas in Java, the salted pulp is rolled into balls, steamed
and sun dried, then exposed to dew for a week before packing in stone jars.
When tamarind is processed for shipment to large-scale processors, the pulp
is removed from the seeds, layered with sugar and then covered with boiling
sugar syrup.
In Sri Lanka, the harvested pods are dried in the sun for 5-7 days to bring all
fruits including the half-mature fruit to the fully ripe stage. The pods are then
cracked to separate the pulp. The pulp with the seed is spread on thick
polythene sheets and dried in the sun for 3-4 days to remove excess moisture
and prevent the growth of moulds. The dried pulp is mixed with salt and
packed in clay pots for storage. These pots are usually kept in a dry place,
preferably in the kitchen. Through this process tamarind can be stored for
about a year, after which the colour changes to dark brown or black and
changes in flavour occur (Samarakoon, 1999, personal communication).
Although pulp is stored with the seeds intact in rural households, seedless
pulp is stored in plastic bags in retail shops (Gunasena, 1997).
These methods are manual and crude and tend to be very labour intensive
and inefficient. Mechanical methods of extracting pulp have been reported
(Benero et al., 1972) and a tamarind dehuller has also been designed and
developed at the Post Harvest Technology Scheme (ICAR), UAS,
Bangalore, India. The machine has a hulling capacity of 500 kg/h, with
hulling efficiency of 80% for large fruits and 58% for small fruits
(Ramkumar et al, 1997 quoted from Rao et al., 1999). Studies carried out by
the same group on storage media indicated that the pulp loss percentage
during storage was very low in black polyethene and plastic compared to
phoenix mat and metal.
The quality and condition of the pulp and the selling price in the market are
often related to the care taken during storage. The freshly prepared pulp is
light brown in colour, but darkens in storage. Generally under dry conditions
the pulp remains good for about one year, after which it becomes almost
black. The pulp also becomes soft and sticky as pectolytic degradation takes
place and moisture is absorbed, especially in humid weather (Lewis and
Neelakantan, 1964 a; Anon, 1976). Continuous storage for long periods
under poor conditions, such as exposure to extremes of temperature and
humidity, is a problem because of changes in colour which take place from
brown or yellowish brown to black (FAO, 1989).
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