Background Report Reference AP-42 Section Number: 9.13.1 Background Chapter: 2 Reference Number: 3 Title: "Developments in Fish Handling and Processing: An Engineering Perspective" in Proceedings of the Institute for Mechanical Engineers J.H. Merritt 1989 AP42 Section ?& I Reference - Report Sect. 2 12s Reference __s Developments in fish handling and processing : an engineering perspective J H Merritt, BE, MSc Canadian Institute of Fisheries Technology, Technical University of Nova Scotia, Halifax, Canada The engineer faces new challenges brought about by demandsror improvedfishery products and the need to make maximum use 01 available resources. In recent years, a/er a period of great expansion, important advances have been made in the handling and processing offish. The wider application ofmodern techniques will enhance the position offish asfood. 1 INDUSTRIAL TRENDS Table I World fish production and disposition (millions of metric tonnes) Fishing and the manufacture of fishery products are tra- ditional activities, fundamental to the well being and llcms 1960 1970 1980 1986 prosperity of the human race. There have been, Fresh 16.9 19.5 15.7 18.2 however, remarkable changes in recent times. Current Froze" 3.5 9.7 15.9 21.4 Cured 7.5 8. I 11.1 13.5 developments in fish handling and processing can be Canned 3.7 6.2 10.3 11.4 viewed in the light of several trends that have exerted a Other 8.6 26.5 18.4 26.9 strong influence. Such an approach might help towards Catch '40.2 70.0 72.0 91.5 anticipation of future needs and developments. Source: FA0 Fishery Slalislia. High demand for fish as food and as animal feed has resulted in great expansion of the fisheries. This, by itself, has prompted change. Fishermen now have access tions are made. Fish processors have participated in this to vessels of advanced design, with sophisticated fish- development by manufacturing a range of fish and fish- finding instruments and fishing gear, for the production based products that incorporate up-to-date features, of more fish for less effort. By the same token, a lot of advanced packaging and ease of preparation for con- methods, equipment and plant have been developed for sumption. ellicient processing of large supplies of fish. Another aspect of the present-day market that is Apart from high demand from a hungry world, there having an effect on the fish industry is the emphasis on are several factors that have had and are having an food wholesomeness and the health-giving attributes of effect on the fisheries. Notable are the need for conser- particular foods. More and more, fish is being viewed vation of stocks of some of the more widely exploited by nutritionists as a most desirable food. Fish oils have species and the extension of fishery limits which have received much attention recently, especially marine had a profound effect on fishing arrangements, trade omega-3 fatty acids, because of claims that they prevent and the policing of fishing zones. One of the outstand- heart disease and other diseases (1). ing changes promoted by the extension of limits has Altogether, therefore, there appears lo be ample been the development of the Alaskan fishery, for opportunity for the fish industry to maintain and poss- pollock, cod, crab, shrimp and other species, by the fish ibly enhance the position of fish and fishery products as industry of the United States of America. Much Euro- a valuable part of the whole supply of food. These pean and Japanese technology has been introduced to factors, mentioned above, amount to new opportunities complement local practices and innovation. and a new challenge for the engineer, who has played a The need to prevent pollution of the oceans is being leading role in the expansion and development of the given greater attention today, with a view to continued fish industry. In the years ahead there will be increased -high_productivity_from_the_fisheries._A qmphasis on improved products that can compete with significance is the increased production and self- other foods, on higher productivity, on maximum use of sulfciency in the lesser developed countries. According fish resources for all and on environmental consider- to FA0 Fishery Statistics from,the Food and Agricul- ations. ture Organization of the United Nations, landings in developing countries reached 48 million tonnes in 1986 and have increased at a greater rate than landings in developed countries (Table 1). 2 EXPANSION OF THE FISHERIES 1950-70 In recent times there has been a strong trend towards The period of 195C70 was one of intense activity in the 'convenience' foods. The introduction of the fish stick fish industry. The world annual catch increased three- (fish finger) more than thirty years ago was a major fold to 60 million tonnes and there were numerous contribution in this direction and promoted a large developments that made catching easier and more pro- trade in frozen fish blocks from which sticks and por- ductive, enabled the handling and processing of increased amounts of fish and promoted the manufac- T),~MS warcceivd on 4 May 1989 and was occeptrdJor publication on 20 July 1989. ture of superior fish products. Eddie (2) has described m8q&I IMcchE 1989 0954-4089/89 S2.W + .OS Pro< lnrtn Mcch Engri VoI 201 ~ 126 1I I1 MEI :In two important mechanical innovations: the power (partial freezing to, say, -2°C) were proposed $, li\ block introduced by Puretic of the United States of regular icing remained the rule. Also, few aids W& m America and freezing at sea, on which much of the introduced to reduce the labour involved; even tod a expansion was based. The power block, consisting of a much of the work is done with a shovel. In powered sheave, gave the ability to handle large nets Cutting (4). in a review of research into refrige la and capture large shoals of pelagic fish. Productivity in of fish and meat, traced the course of developm m the more highly mechanized fishing fleets reached high techniques for chilling and freezing of fish, with fa levels, particularly when fishing for supplies for fish sis on the pioneering work done from about 1930. Ci meal and oil manufacture. Thus, Peru, as an outstand- Many of the more important changes du Ci ing example, attained a harvest of more than IO million period 1950-70 had to do with mechanizat fc tonnes of anchovy per year. cessing operations. Machines for filleting, The large-scale adoption of freezing at sea was (removal of heads and guts), heading, splitting, ri prompted by a need to fish in waters distant from home skinning, sorting according to size etc. were in h without restrictions on the duration of voyage imposed widely. In the main, the objectives were to s1 by the perishability of fish stowed in melting ice. This labour and increase productivity. In some instan C was a European development of the period, as described machine was needed to cope with large F n by Waterman (3), and was based largely on technologi- small fish while in other cases the machine I cal work at Torry Research Station in the United on grounds of increased yield. There were major changes in the production of cu S Kingdom. By 1970 there were about a thousand t freezing-at-sea trawlers, mother ships and refrigerated fish products. Mechanical dryers displaced traditio transport vessels of over lo00 tonnes, some of them methods of drying out of doors for the p > over 1Oo00 tonnes. dried salt fish in Scandinavian countr I Of course there were other important developments Canada and other countries. These enabled the ind 1 during the period 1950-70, many of them concerned to increase production and reduce losses due to directly with the fishing vessel. Advances were made in weather conditions. insect infestation etc. Mecha I fish finding and navigation. Trawl gear was made more smoking kilns were introduced widely in Europe and elficient and the large midwater trawl was developed. elsewhere; they found favour as a means of increasin The early freezing-at-sea vessels incorporated important production and reducing losses. The change to mech-', innovations, notably the provision of a shelter deck for anical kilns was accompanied by a shift towards mild' , handling and processing of the catch, arrangements for cures-products of relatively low salt content and with !' handling the trawl over a stern ramp instead of over the less drying and, smokingdependent on refrigeration ,,l. side and the vertical-plate contact freezer developed for for preservation. Weight loss on the smoking of herring ;I the freezing of whole fish on board. While there had (kippers) in the United Kingdom was typically 25 per 4 been earlier ventures into freezing at sea in certain cent forty or fifty years ago but by 1970 values had specialized fisheries, success in the 1960s was based on declined to about 10 per cent. improved equipment and methods. These improvements included machines from Germany for automatic filleting of fish, electronic fish finding and navigation equipment, 3 NEW DEVELOPMENTS modern propulsion and refrigeration machinery and 3.1 Some aspects of production plastic (thermal) insulation materials. Knowledge of good freezing and cold storage practices, especially the Since 1970 expansion has slowed; the world catch in establishment by Reay and his colleagues (4) of -30°C 1986 reached 91.5 million tonnes and there is wide as the recommended temperature of storage, was a vital agreement that the sustainable limit cannot be much e I em enI. greater than 100 million tonnes. Some stocks have been Another major development for preservation of the depleted through overfishing.