The influence of protein adjuncts and variations in pH on the cook-cool loss, moisture content, and texture of squid gels was investigated. Break force (P [greater than or equal to] .025), deformation to break (P [greater than or equal to] .01) and cook-cool loss (P [greater than or equal to] .001) decreased as the pH of squid gels was adjusted from 6.4 to 8.3 with sodium carbonate. The moisture content of gels increased (P [greater than or equal to] .01) as the pH was elevated. Break force (P [greater than or equal to] .001) and deformation distance to break (P [greater than or equal to] .005) were inversely correlated to gel moisture content. Protein adjuncts (2%) had a significant effect on cook-cool loss, break force and moisture content (P [greater than or equal to] .001, .026, and .018, respectively) of squid gels. Egg white produced an improved water-holding capacity over soy protein isolate and sodium caseinate. The mean cook-cool loss from gels containing egg white was 5.29 + 0.66% which was significantly (P=.05) lower than that of gels containing soy protein isolate (12.41 + 0.17%), no protein adjunct (16.65 + 3.82%) and sodium caseinate (19.75 + 2.42%). Gels containing sodium caseinate had a significantly (p [greater than or equal to] .05) lower moisture content and higher cook-cool loss (P=.05) than gels containing egg white or soy protein isolate. The break force of gels containing sodium caseinate could not be measured because the gels possessed little fracturability when compressed. The break-force of gels containing soy protein isolate or egg white were equal (P=.05), but each was less (P=.05) than observed for control gels. Holding minced squid gel sols at 4°C for 4 and 24 hours before forming and heat-setting into gels, had a significant effect on the force required to break gels (P [greater than or equal to] .001) and expressible moisture (P [greater than or equal to] .006). Control squid gels and gels containing soy protein isolate that were formed after holding for 24 hours required a lower force (P=.05) to break gels than similar gels formed after holding for 4 hours. Holding time did not alter (P [greater than or equal to] .05) moisture content, cook-cool loss or deformation at break. Reduced gel strengths observed for gels held for 24 hours prior to heat-setting was related to protease activity, loss of reactive sulfhydryl functions and/or cold temperature setting. A restructured seafood product was fabricated from mantle and tentacle muscle of squid (Loligo opalescens). Whole squid yielded 37.5 + 1.4% edible mantle and 15.3 + 1.0% tentacle meat; a total yield of 52.2 + 2.4% based upon round weight. A restructured product fabricated from heat-set fibers (60%) and squid sol (40%) yielded 33.4 + 1.0% based upon round weight. A consumer preference panel found no (P [less than or equal to] .05) differences in the product containing different protein adjuncts and judged the product to be, at least, slightly desirable (score of 6.0 on a 9 point scale). Firmness was the only sensory attribute that a trained panel found to be influenced (P [greater than or equal to] .05) by the incorporation of protein adjuncts. The product containing sodium caseinate was judged to be less firm (P=.05) than products incorporating either egg white or soy protein isolate. Trained panel scores for firmness were consistent with measurements for break force. / Graduation date: 1988

A method was devised and tested for rapid and quantitative identification of microbial flora in fresh seafoods. The rapid identification of large numbers of isolates was made possible by (1) a simplified identification scheme established by reference culture studies and from the known reactions of microorganisms reported in the literature, (2) the multiple transfer of large numbers of isolates by means of replica-plating, and (3) the use of an electronic computer to analyze data. For the identification of microbial isolates, colonies developing on initial isolation plates were picked by sterile toothpicks and inoculated on a master-plate in prearranged spacing and order. Growth on the master-plate was replicated on a series of solid agar plates containing differential or selective agents. Identifying characteristics consisted of growth responses of the isolates on media containing penicillin, tylosin, vancomycin, streptomycin, chloramphenicol, neomycin and colistin; growth responses on Bacto-SS, Bacto-S-110, Bacto-potato dextrose agar; and culture pigmentation, cell morphology and the Gram-reaction. Information was processed by an IBM 1410 digital computer which sorted and grouped each isolate into one of ten microbial genera or groups, according to a programmed identification key. The identification system was tested by analyzing the microbial flora of dover sole fillets (Microstomas pacificus) and ground beef. This rapid identification method was employed in an investigation designed to determine the nature of the microbial flora shifts in dover sole resulting from irradiation and storage at 6°C. The relationship between the microorganisms which initially survive irradiation, and those making up the final spoilage flora, was determined. A total of 2,723 isolates were examined in this study. The spoilage of unirradiated control samples during storage at 6°C was almost entirely due to the growth of Pseudomonas. This group, which occupied 25 percent of the fresh flora, grew up to nearly 100 percent in two days storage. In contrast, irradiation doses of 0.1, 0.2, 0.3, and 0.4 megarad favored the growth of Achromobacter and yeasts. Micrococcus species, which survived radiation, did not grow at 6°C. At 0.5 megarad, spoilage of fish samples at 6°C was due entirely to yeasts. / Graduation date: 1966

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This research investigates the livelihoods of artisanal fishing families at Lake Malawi. The key research question that it addresses is how artisanal fishers adapt their behaviour to cope with fluctuations in fish availability that occur naturally, i. e. that do not occur primarily as the outcome of human fishing behaviour. In Lake Malawi two such fish species, usipa and utaka, exhibit considerable spatial, seasonal, and interannual variability. These species are also by far the most important for the artisanal fishery. Fluctuating fisheries pose special challenges for livelihoods and fisheries management. For livelihoods they imply big seasonal variations in the ability of families to rely on fishing as a primary livelihood component, and they make fishing-based livelihoods insecure and risky. For fisheries management, they pose the problem that the true status of the resource is almost impossible to measure, with apparent risks in both directions: that overly restrictive management will result in an unexploited resource that could have made a greater contribution to the livelihoods of poor people and to the nutritional status of the population of Malawi more generally; or that overly lax management will result in a depletion of the resource beyond its sustainable yield. The research shows that fishers adapt to the fluctuating fish stocks in two main ways. One way is to specialise mainly in fishing but to emphasise mobility, so that short and medium term movements around the lake are made in pursuit of the resource. The other way is to maintain diverse livelihoods, combining fishing with farming and other non-farm income generating activities. There are, of course, also intermediate cases between these two opposing poles. The research demonstrates that migration for fishing purposes brings benefits both to migrants and resident communities. While for the migrants it is important to be allowed to settle for varying periods at different lakeshore beaches and villages; for residents the presence of the mobile fishers brings an increase of cash into circulation, the arrival of fish traders, the ability to open shops and bars to service this increased activity, and more buoyant markets for locally produced commodities. There are thus important income and employment benefits for resident communities that result from the behaviour of fishing migrants. At Lake Malawi, migrant fishermen tend to be from the Tonga ethnic group from the north of the country, and they generally differ in ethnicity from the resident communities where they take up temporary settlement. Fisheries policy in Malawi has been moving away from a top-down regulation by the Fisheries Department towards the idea of community management of fisheries. The argument is that if fishing communities are given their own powers to enforce regulations, within a participatory framework, then community self-interest will ensure that regulations are properly policed. This idea involves establishing territoriality over areas of the lake, so that "beach village committees" (BVCs) have regulatory powers over the lake areasa djacentt o villages. The researchd emonstratesth at there are many flaws in this concept in the case of Lake Malawi: BVCs are dominated by part-time fishing or non-fishing residents, migrants are excluded, territoriality is nonsensical for a mobile resource, and previously successful reciprocal relationships and other complex adaptive strategies are weakened and disrupted. The artisanal fishery in Malawi is opportunistic; it adapts to fluctuations either by ceasing to fish or by moving to other fishing grounds. It is argued that this sort of fishing requires minimal management, in which mobility and diversity are recognised and encouraged. If indeed there is a threat to the resource, it is rather the large scale commercial sector comprising a few trawlers of immense capacity relative to the yield potential of the Lake that pose that threat. There is an unequivocal need to monitor and regulate the catch volumes of this sector. For the artisanal fishery, however, a low key, flexible and resilient management approach is suggested; one that builds on the strengths of existing patterns of behaviour rather than seeking to change and undermine them.

Fung Sing Chung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1980. / Bibliography: p. leaves 64-68.

This is a study of the food of pond fish in northern Utah. The species examined in the family Centrarchidae were largemouth black bass, Micropterus salmoides (Lacepede), green sunfish, Lepomis cyanellus Rafinesque, and common bluegill, Lepomis macrochirus Rafinesque, together with black bullhead, Ameiurus melas (Rafinesque) of the family Ameriuridae. Specifically it is a report of the macroscopic food found in the stomachs of sub-adult and mature fish. Although such a study is of predominant interest to the biologist, who is interested in life history and ecological relationships of fish, the farmer or small businessman can find the data applicable. This is because onds serve in one way or another in soil and water conservation programs, as recreational areas, or as commercial enterprises for bait, sport, and food.

This thesis is composed of two studies: (1) an assessment of the vertical habitat use of swordfish Xiphias gladius in the Florida Straits; and (2) a systematic description of the southeast Florida recreational swordfish fishery. First, the vertical distribution of swordfish (Xiphias gladius) was assessed in relation to diel cycles and lunar phase from data gathered utilizing popup satellite archival tags (PSATs). Seven tags were deployed in the Florida Straits during this study from recreational and commercial fishing vessels; two fish died shortly after deployment, and the remaining five were included in the analysis. Tags were deployed for periods ranging from 120 to 151 days and recorded data on temperature, depth, and light level every ten seconds. Transmitted data was summarized into one hour histograms. Swordfish vertical distribution in response to diel cycles was characterized by typically spending daytime hours below 500 m and nighttime hours in waters less than 75 m. Swordfish distribution differed significantly in response to lunar phase, with animals occupying successively deeper depths in response to increasing lunar illumination. This study is consistent with the widely accepted hypothesis that the swordfish vertical distribution is a function of ambient light levels. However, in contradiction to this hypothesis was the observation of a number of daytime surfacing events recorded by the tags. This less pronounced but frequent behavior is hypothesized as a mechanism to warm the fish?s body after extended daytime feeding dives to great depths. A recreational fishery targeting swordfish in southeast Florida has gained popularity in recent years. However, little data is currently available on the fishery and its participants. A survey was distributed to recreational swordfish anglers at local swordfish fishing club meetings and a swordfish fishing tournament to describe the fishery and its participants. Questions were organized into four sections: demographics, fishing habits, cost, and views on regulations. A total of 38 surveys were completed by anglers and included in the study. Recreational swordfish fishermen in southeast Florida were mainly Caucasian, with the largest group by percentage ranging from 41-50 years of age. Most fishers surveyed had over 20 years recreational fishing experience, with less than 10 years experience targeting swordfish. Anglers typically fished out of center console boats ranging from 21-35 feet, and usually made less than 50 trips per year. Costs associated with the fishery typically exceed those associated with general recreational saltwater fisheries by thousands of dollars (USFWS, 2006). Fishers were divided in their views on the current recreational swordfish regulations. Forty percent of anglers surveyed were unsatisfied, 37% were satisfied, and 23% remained neutral.

Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 93-99). Also available on the World Wide Web.