4 °C - the National Sea Grant Library

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MATERIAL AND METHODS
Product Preparation. Live commercially harvested tilapia were obtained from the
Aquacultural Experimental Station of in Lajas. P. R. Their body weight and length was 90 -
100 g (average 92 g) and 17 - 18 cm long for tilapia. After the fish were chillkilled and rinsed
with water, the scales, head, tail, viscera and backbone were discarded. The remaining was
precooked in a conventional oven at 35OOF. precooking times were 0 , 10,20, or 30 min. The
precooked tilapia were cooled and packed in 30l x 41l cans with sufficient patching to give a
net weight of 535 f. 5 g , with 230 f 5 milliliter portions of canned tomatoe juice seasoning ,
vegetable broth, or distilled water were then placed on top of the meat, leaving a headspace of
about 10 mm. All cans were sealed (Dixie model 24 eletric set to close cans), immediately after
being exhausted for 15 min. (Fisher scientific model 139, serial 115). The cans were then steamretorted
at 1OOOC for 87 min, allowed to cool under running water, and stored at room
temperature for subsequent analysis. According to the food and Drug Agency, a manufacturer
must thermally process acidified foods sufficiently to destroy all vegetative cells of
microorganisms of public health concern 11 .
CONCLUSION
Fisheries statistics indicate that the Puerto Rico fisheries resources are declining.
Evidence of this are: a) decrease in number of pounds landed; b) the selling of species, that in the
past did not have commercial value; c) large percentages of individuals of commercially
important species being caught prior to obtaining miriirnum size of sexual maturation. Puerto
Rico with its tropical climate has the advantage that it could develop aquaculture systems that
produce the year round, that could satisfy part of the demand of the consumption of the fish to
local level. Besides the fish that are highles marketable the possibility of beins able to turn
small, unsellable fish into a product that would generate additional revenues for the producer
would only improve the economic viability of tilapia production in Puerto Rico. By determinig
consumer acceptabel and sensory characteristics of stunted and non-stunted tilapia it should be
posible to determine the commercial valve of this unutilized resource.
1.
2.
REFERENCES
Lo&in, L. 1990. Water Food (Tilapia ), in Seafood Business. 9 (5): 146 - 149 P.
Pulin , R. S. V. and Lowe-McConell, R. H. 1982. The Biology Culture of Tilapias.
ICLARM. Manila, Philippines. 415 pp.
3. Arias, S. y Wiscovich, S. 1989. Acuicultura (Datos T&r.icos para su desarrollo),
proyecto de Acuicuhura de1 Servicio de Asesoria, Manual de1 programa de Sea Grant y
el Servicio de Estension Agricola de la Universidad de Puerto Rico, Publication #
UPRSG-G-40. 12 p.
4. Hepher, B. y Pruginin Y. 1991. Cultivo de Peces Comerciales. Editorial Limusa, S.
A. Baleras Mexico 316 pp.