Canning of in oil

Item Type article

Authors Madhavan, P.; Balachandran, K.K.

Download date 27/09/2021 07:00:31

Link to Item http://hdl.handle.net/1834/33548 P. MADHAVAN AND K. K. BALACHANDRAN Central Institute of Technology, Ernakulam, Cochin-11

This paper provides the experimental details of canning of tuna in oil. The species utilized in the experiments were the skipjack (Katsuwonus pelamis), (Neothunnus macropterus) and Parathunnus obesus mebachi) ranging in weight from 2.5-82 kg. The method worked out is applicable to an species ()f different size grades,

iNTRODUCTION elsewhere in the main coast, a portion is Occurrence of tuna, though reported locally consumed in :fresh condition and from many regions on the west and east the rest cured and exported in the form coasts of India, is mainly confined to the of mas min, the process of preparation of regions around Laccadives. The spices of which has been described by Valsan (1968), larger sizes are generally adapted to the until a canning plant was established ocean. The skipjack is caught in appreci­ recen Hy by the Laccadive Administration able amounts around Minicoy. Though in the island of Kavarathy. Canned tuna the smaller species like Euthunnus afflnis is a product commanding a large market I and E. are met with in all warm in U. S. A., Canada, U. K. and also waters they are not generally used for Western and Eastern Europe. Canning of canning or freezing. Species like Kishion­ this fish has not been practised to any el!a tunggol, Neothunnus macropierus, appreciable degree, although efforts are Parathunnus obesus are larger in size, currently being made in regions where this but are caught in relatively fewer numbers. fish is available. However, there occurs However, with the introduction of tuna wide variations in the method adopted for long lining and other improved gears the canning this fish in different regions. catch of these species is expected to Realising the vast scope for the develop­ increase to a very appreciable extent. In ment of the internal trade as also the good 1968 Jndia landed 3690 tonnes of tuna. international market for this commodity, (CMFRf, 1969). the Indian Standards Institution has laid Of the large catches of skipjack in down quality standards for tuna canned Minicoy island and other available catches in oil (IS: 4304-1967).

VoL VIII No. 1 1971 23 As regards the technological aspects room (3-5°C). The softend skin was · "Jf processing, tuna canning has not scraped off using a stainless steel knife and "eceived the attention it deserves. Finch the flesh seperated into halves from both (1962) has givtm a detailed account of sides of the backbone. The portions were canning of hma in U. S. A. Recently again divided horizontally and the black Central Institute of Fisheries Technology meat removed completely. The loins were published (Anon., 1964) a method for polished by rubbing off the loose fragments canning of tuna in oi], but did not discuss of flesh. the various technological aspects when applied to fishes of different size grades. iv) Processing: The loins were Considering this, further detailed work was cut to suit the size of the can. 170 g undertaken paying due attention to the material was packed in cans of size 301 x various aspects of the problem with a view 206 followed by 50 ml hot refined ground­ to turning out a product conforming to the nut oil providing for sufficient head space. IS specifications using different sizes and Cans were exhauste

24 TECHNOLOGY TABLE I RELATIONSHIP BETWEEN TIME OF The cooked pieces can be cooled COOKING AND WATER IN FILLING QIL either in a current of air or in a cold room. The latter has got definite advantag<2s over the former. since the flesh becomes hard enough to permit easy scraping off of the skin and cleaning the loins free from black meat with minimum flaking offles.h (Finch., Joe cit).

Dipping of the cut pieces in 15% brine containing 0.075% sodium bicarbonate (added as a softening agent to give a tender texture to the product) for 22 minutes (Anon., 1964), though imparts a proper saltish taste and good texture to the product, is invariably accompanied by the bulk quantities are cooked as in commercial risk of increasing the volume of water in practice, it is advisable to prolong the oil above that prescribed by I. S. specifi­ cooking to such a period that the backbone cations by the brine adhering to the pie<:es attains a temperature of 93-94°C when the together with any water expelled from the water in filling medium can be kept flesh due to insufficient precooking. minimum. The same conditions were found to be applicable to fishes of all size grades. Alternatively, addition of solid sah to the meat packed in cans can be advantage­ Time taken by fish of different sizes to ously adopted. 2% salt on the weight of attain a temperature of 93.5°C at the the packed meat, containing 0.5% sodium surface of the backbone is presented in bicarbonate, has been found to serve the Table II. same purpose as the brining mentioned earlier. Concentration of bicarbonate TABLE H TKME TAKEN BY FKSH OF DIFFERENT above 0.5% in sah definitely impmves the SIZES TO ATTAIN 93.5°C texture, but is accompanied by bleaching Steam pressure; 0 84 kgjsq em. of the natural pinkish colour of the flesh and impairing of the flavour. Species Length Thickness Weight Time to in. w. kg. reach 93.5°c SUMMARY Hrs Min. Big eye tuna A process for canning tuna in oil (round piece) l2 10 16 3 00 which is applicable to all size grades is 10 8 12 2 45 described as a modification of the process " Skipjack reported earlier from this laboratory. (Whole fish) 14 4 3 1 10 Fish has to be precooked for such a period Big eye tuna that the surface of the backbone attains a (fillet) 10 5 6 15 temperature of 93-94°C so as to keep down the water content in the filling oil to The temperature was measured by the minimum and then cooled in a cold inserting a copper-constantan thermo~ room to facilitate easy handling during the couple (20 SWG) and read over a subsequent stages of processing. Addition Cambridge pyrometer. of solid salt instead of brining dispenses

VoL No. 1 1971 25 with possibility of introducing any REFERENCES water into the filling oil in addition to that Anon., 1964, Fish Technology News from the fish muscle. Incorporation of Letter, 4 (4), 1-2. of 0.5% sodium bicarbonate on the basis CMFRI.. 1969. Marine fish production of salt gives a good texture to the product. in India, Bulletin No. 13, Central Marine Fisheries Research Institute, ACKNOWLEDGEMENTS Manda pam, The authors wish to express their Finch, Ronald, 1962. Fishing News sincere thanks to Dr. V. K. PiHai, Fishery International, I (4), 23-30. Scientist for the valuable guidance during IS 4304-1967,/ndian Standard Specification the course of the work and to Shri G. K. for Tuna canned in oil. Kuriyan. Director-in-charge, for kind Valsan A. P. 1968, Fish Techno!, 5 (1), permission to publish this paper. 37-41.

26 FISHERY T!ECHNOLOG Y