SPOILAGE IN DRIED SHRIMPS
By K. GOPINATH, B.A., M.Sc., Assistant Research Officer, Department of Marine Biology and
Fisheries, University of Travancore, Trivandrum
(Received for publication on 23 September 1942)
THE families Penæidæ and Palæmonidæ are
represented in Travancore by 18 species which fall
under six genera. Of these, Penaeus monodon
Fabr. Alcock., P. indicus M. Edw., P. carinatus
Dana (de Man), Metapenaeus monoceros (Fabr.),
M. affinis (M. Edw.), Metapenaeopsis dobsoni, var.
nov., Parapenaeopsis maxillipedo Alcock., and
P. stylifera (M. Edw.), belonging to the family
Penæidæ, constitute the bulk of the commercial
'prawns' of this State.* Palaemon carcinus
Fabr., P. idae Heller. and P. dayanus Henderson,
belonging to the family Palæmonidæ, are fresh-
water forms and though they are fished in large
quantities, find only a local market. It may,
however, be pointed out herein that the use of the
common term 'prawn' for all the species is a
misnomer which by common usage has supplanted
the more accurate and accepted term 'shrimp'.
This implies that a great portion of what is known
as prawn fisheries of this State is really shrimp
fisheries and this distinction between the two types
of fisheries is important for classifying the various
sections of the fishing industry. Though prawn
fishing is by no means unimportant, commercial
shrimping maintains a business which yields
more than 15 lakhs of rupees per annum and
supports more than twelve thousand fishing
families of the State, who live exclusively by this
industry.
It may be impossible to trace the origin and
development of shrimping in Travancore though
it may safely be asserted that it has been in
existence from very early days as shown by
certain indirect historical evidences. It is
probable, however, that intensive fishing is only
of recent origin, as indicated by the fact that there
are even now suitable areas which remain un-
exploited. During recent years shrimp fisheries
have developed in various parts of the world.
Chopra [1936], reviewing the report on the Cape
Crawfish Industry of South Africa, has given a
vivid account of the rapid development the
industry has undergone in recent years as a result
of careful scientific investigations. Chopra [1939
again describes how the prawn industry of Norway
has remarkably grown in the last thirty or forty
years. The shrimp industry of the United States
of America has grown markedly in the past two
decades and today probably it is the biggest shrimp
producing country in the world. In 1931, which
was only an ordinary year for shrimps, U. S. A.
produced 98,765,943 lb. of shrimps valued at
3,526,864 dollars [Johnson & Linder, 1934].
It was the discovery of foreign markets which
stimulated the rapid development of our industry
and more than 85 per cent of our catch is exported
to foreign markets. Since the industry developed
on the normal stimulation of demand, unaided by
technical or scientific control, it is still in a pri-
mitive condition. The methods of production,
preservation and packing now adopted show that
a great deal still remains to be perfected before
the industry can be put on a sound commercial
basis.
The shrimp fisheries of Travancore depend for
their success on the presence of a chain of back-
waters permanently connected with the sea.
These backwaters afford excellent feeding
grounds and into these the young of shrimps
migrate in large numbers [Panikkar, 1937].
Here they undergo development for about an
year and then return to the sea for breeding.
During this migration and also during their stay
in the backwaters, they are caught in large quanti-
ties by means of various devices.
The method of preservation mostly followed
in this country is very simple; the hauls are
thrown into circular copper vats with small
quantity of water and heated till they are semi-
cooked and turn red in colour. Brine is seldom
used here, though it is a common practice along
the Sind Coast [Rai, 1934]. The semi-cooked
shrimps are then dipped, drained and spread on
mats and allowed to dry in the open sun for a
couple of days. When they become quite dry
and crisp, they are gathered in gunny bags and
thrashed on a thick log of wood to remove the
head, shells, appendages and the other smaller
tissues usually termed 'bran'. This completes
the process of preparation. Without further delay
the meat is packed in gunny bags and sold to
merchants who make quick arrangements for the
disposal of the commodity. Thus it will be seen
*From the systematic survey of the ' prawn fauna '
of Travancore conducted by Mr Natarajan of this
Laboratory. The paper is under publication.
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