Preliminary studies on nutritive and organoleptic properties in processed fish fillets obtained from Iran

The effects of boiling, frying, and roasting methods on nutrients and properties some of marine fishes were studies. AOAC official methods were used for the analyses of the samples. Frying reduced the protein content of Nemipterus japonicas, while roasting reduced the protein content of Carangoides malabaricus and Saurida undosquamis. Fresh and fried C. malabaricus had 71.2% and 57.05% protein content, respectively, while N. japonicas had 57.39% and 47.51%, respectively. The highest oil content in C.malabaricus was 16.80%, followed by N.japonicus 12.80%; while the lowest oil content in S.undosquamis was 5.88%. N.japonicusis protein content reduced with frying. Some cooking methods used in the processing can have an effect on of fish nutrient composition. The texture of fried and boiled fish fillets significantly differ from that of the roasted fillets (p<0.05).

Designing and validating the methodology for the Internet assessment of fish consumption at a university setting

Assessing fish consumption is complex and involves several factors; however, the use of questionnaires in surveys and the use of the Internet as tool to collect data have been considered promising approaches. Therefore, the objective of this research was to design a data collection technique using a questionnaire to assess fish consumption by making it available on a specific home page on the Internet. A bibliographical survey or review was carried out to identify the features of the instrument, and therefore pre-tests were conducted with previous instruments, followed by the Focus Group technique. Specialists then performed an analysis and conducted an online pre-test. Multivariate data analysis was applied using the SmartPLS software. The results indicate that 1.966 participants belonging to the University of São Paulo (USP) community participated in the test, and after the exclusion of some variables, a statistically significant results were obtained. The final constructs comprised consumption, quality, and general characteristics. The instrument consisted of behavioral statements in a 5-point Likert scale and multiple-choice questions. The Cronbach's alpha reliability coefficient was 0.66 for general characteristics, 0.98 for quality, and 0.91 for consumption, which indicate good reliability of the instrument. In conclusion, the results proved that the Internet assessment is efficient. The instrument of analysis allowed us to better understand the process of buying and consuming fish in the country, and it can be used as base for further research.

Effects of filtration methods on the neutralization yield of crude marine fish oil

The evaluation of filtration methods on the yield and oleochemicals characteristics on the crude fish oil from the soapstock of marine fish for purposes of nutrition has been conducted in this work. The analytical properties of the crude and the neutralized oil with three excesses of sodium hydroxide (NaOH, 20%, 40% and 60%) were carried out on two different ways with organza and the “glass wool”. The neutralization of the oil brought about a notable improvement in the analytical properties of the oil. Thus, it leads to a high quality fish oil in terms of taste, colour, odours, shelf life and market value. Based on the improved characteristics of the oil, it could be suitable for applications in pharmaceutical and food industries.

Characterization of a hydrolyzed oil obtained from fish waste for nutraceutical application

The fish industry generates high volume of waste from fish oil that can have the extraction of its lipids used as nutraceuticals and foods. The objective of this study was to produce unsaturated fatty acids from industrialized fish oil by means of a differentiated hydrolysis process. The samples used were crude fish oil obtained from Campestre industry and characterized through physical-chemical parameters, according to AOCS: acidity, peroxide, saponification, iodine and percentage of free fatty acids and also obtained the fatty acid profile through derivatization method for gas chromatography. The results obtained for the oleochemical indices for refined oil were similar to the data found on the literature. The content of polyunsaturated fatty acids (PUFA) was found of 32,78%, with 9,12% of docosahexaenoic (DHA) and 10,36% of eicosapentaenoic (EPA), regarding monounsaturated fatty acids (MUFA) content was of 30,59% in the hydrolyzed fish oil in relation to refined (20,06%). Thus, it can be concluded that the hydrolysis process used for oils from fish-waste was satisfactory on the production of absolute yield of lipids in the process and significant preservation on the percentages of EPA and DHA, interesting on the production of nutraceuticals and nutrition of aquatic animals, including shrimp in captivity.

Fish consumption preferences and factors influencing it

Fish consumption preferences are affected by individuals’ socioeconomic characteristics. The aims of the present paper were (i) to obtain information on fish consumption level and frequency; (ii) to investigate the associations between the socioeconomic characteristics of consumers and their preferences; and (iii) to examine the influence of determinants on fish consumption. Data were gathered through a questionnaire completed by a total of 127 randomly selected individuals from different socioeconomic backgrounds from the Antakya, Turkey. The average consumption was found to be 2.98 kg/person/year for fish. Anchovies, gilt-head sea bream, and sea bass were reported as the most consumed three species, respectively. Significant differences in fish consumption were found among age groups, gender groups, and education groups, as well as between marital statuses. A majority of the consumers eat fish once a month throughout the year or only during the winter months. Fish consumption level and frequency were significantly positively correlated with education (p<0.01), income (p<0.05) and total meat consumption (p<0.01). The stepwise multiple regression model explained 41.7% (p<0.01) of the total variance for fish consumption. The amount and frequency of the consumption in the region, which is very far below the world and Turkey average especially for lower socioeconomic groups and for less-consumed fish species, can be increased by certain policies, such as training, advertising and different marketing strategies. Moreover, consumption should be distributed equally throughout the year instead of consuming only in certain seasons.

Sensory acceptability and fatty acid profile of fish crackers made from Carassius gibelio

Abstract In this study, our aim was to consider the production of fish crackers using Carassius gibelio and to investigate the fatty acid profile and sensory quality of the fish crackers. Fish cracker mixture with a ratio 3.5:1.5 (minced fish/wheat starch) was obtained. Based on the total minced fish and starch level, 1.75% salt, 0.25% black pepper, 2% sunflower oil, 1% baking powder and 10% cold water (4 °C) were added and stirred until a homogenous mixture was obtained. The mixture was compressed in an extractor and baked. The moisture content of minced fish (CMF), cracker dough (CD) and crackers (CCr) was 77.73 ± 0.14%, 63.10 ± 2.18% and 7.95 ± 0.67% respectively. The n6/n3 ratio of crackers was 2.61 ± 0.20, PUFA/SFA ratio 2.28 ± 0.06 and DHA/EPA ratio 1.81 ± 0.01. The overall acceptability score obtained by the sensory evaluation of panelists was very high (8.09 ± 0.25).

Extruded snacks with the addition of different fish meals

Abstract Tilapia, salmon, tuna and sardine meals were prepared to develop and analyze extruded snacks with residue meal from fish processing. Residue meals were included in five types of corn snacks: control (0% fish meal) and four with 9% tilapia, salmon, tuna and sardine meals. Although moisture, lipids and carbohydrates rates did not differ among the snacks, protein rates increased with the increment of fish meal, reaching 11.85% in the tuna snack. Tuna and sardine snacks had the highest iron levels. The most abundant fatty acids were linoleic, oleic, palmitic, linolenic and stearic acids, with sardine, salmon and tuna snacks presenting the highest values of n-3 series fatty acids. Greater luminosity rate was reported for salmon snack, followed by tilapia, tuna and sardine snacks. The highest sensory acceptance index was verified in tilapia (78.07%) and salmon (72.40%). A 9% addition of residue meals of tilapia, salmon and tuna improved the nutritional value of the snacks.

The effect of relative humidity on tensile strength and water vapor permeability in chitosan, fish gelatin and transglutaminase edible films

Abstract Composite films of chitosan, fish gelatin and microbial transglutaminase (MTgase) were developed. Films were produced by the casting method and dried at room temperature for 30 h, conditioned for 7 days at 30 °C at a relative humidity (RH) from 11 to 90%, and characterized. Chitosan:fish gelatin films in different proportions (100:0, 75:25, 50:50) with MTgase, were subjected to tensile properties and water vapor transmission (WVT) testing. The results showed that tensile strength decreased with an increase in RH and with an increase in gelatin content. Percent of elongation also increased with increasing RH and gelatin concentration. Water vapor transmission showed an increase proportional to an increase in RH with the presence of gelatin being unfavorable for reducing WVT. Results in this work allowed studying the effect of relative humidity on tensile and water vapor properties of chitosan and fish gelatin films.

Check all that apply (CATA) as an instrument for the development of fish products

Abstract The objective of this paper is to develop a fish-based product. Through the innovative sensorial check all that apply (CATA) technique, employed in two stages of the development of the product – market research and the sensorial and hedonistic characterization of the final product – the aim was to develop a fish by-product that could respond to the needs of the consumer market. Results showed that the CATA technique is an important instrument for researching the consumer market and indicated the kind of fish by-product to be developed and its desired features. Nugget was the resulting by-product. The second application of CATA made possible the sensorial description of the by-product as being crisp, with little fish odor, light in color, well-seasoned and tasty. Therefore, the CATA technique proved to be an important research instrument in the fish consumption market as well as a quick technique for the complete description of fish nuggets.

Diel patterns and tissue-specificity of environmental responses in fish

Humans are profoundly changing aquatic environments through climate change and the release of nutrients and chemicals. To understand the effects of these changes on natural populations, knowledge on individuals’ environmental responses is needed. At the molecular level, the environmental responses are partly mediated by chances in messenger RNA and protein levels. In this thesis I study messenger RNA and protein responses to an assortment of environmental stressors in fish. As daily (diel) rhythms are known to be ubiquitous in different tissues, I particularly focus on diel patterns in the responses. The studied species are the three-spined stickleback (Gasterosteus aculeatus L.) and the Arctic char (Salvelinus alpinus L.), both of which have circumpolar distribution in the Northern hemisphere. In the first two studies, three-spined sticklebacks were exposed to both the non-steroidal anti-inflammatory drug diclofenac and low-oxygen conditions (hypoxia), and their responses measured at separate time points in the liver and gills. The results show how the seemingly unrelated environmental stressors, hypoxia and anti-inflammatory drugs, can have harmful combined effects that differ from the effects of each stressor alone. Moreover, both stressors disturbed natural diel patterns in gene expression. In the third study, I studied the responses of three-spined sticklebacks to two test chemicals: one used in hormonal medicine (17α-ethinyl-oestradiol) and one used as a plasticizer and solvent chemical (di-n-butyl phthalate). The results suggest that the phthalate can affect genes related to spermatogenesis in fish testes, while estrogen-mimicking compounds can lead to numerous disturbances in the endocrine system. In the final study, the temperature-dependence of diel rhythms in messenger RNA levels were evaluated in the liver tissue of the Arctic char, a cold-adapted salmonid. The results show that cold acclimation repressed diel rhythms in gene expression compared to warm-acclimated fish, in which the expression of hundreds of genes was rhythmic, suggesting the circadian clock of the Arctic fish species can be sensitive to temperature. Overall, the results of the thesis indicate that fishes’ responses to abiotic factors interact with their diel rhythms, and more studies on the consequences of these interactions are needed to comprehensively understand human impacts on ecosystems.

Trends in fish prey capture by common terns following zebra mussel invasion : do terns track fish species abundance? /

The Common Tern (Sterna hirundo) is a ground nesting colonial seabird. Terns rely primarily on small prey fishes which they obtain through plunge diving for their survival as well as the survival of their offspring during the breeding season. The zebra mussel (Dreissena polymorpha) is a small bivalve mollusk that invaded North American waters in the late 1980's. Through its suspension feeding, the zebra mussel has the ability to alter the entire aquatic ecosystem, ultimately leading to a reduction in pelagic organisms including small prey fish. The objective of the study was to determine what (if any) indirect effects the invasion of the zebra mussel has had on fish prey captured by terns. The study took place in two separate two-year periods, 1990-91 and 1995-96 on a concrete breakwall off the north shore of Lake Erie near Port Colborne, Ontario. Daily nest checks revealed clutch initiation dates, egg-laying chronology, hatching success and morphological egg characteristics (length and breadth). Behavioural observations included time each sex spent in attendance with its brood, the frequency of feeding chicks and the prey species composition and size fed to chicks as well as to females (courtship feeding). Egg sizes did not differ between study periods, nor did feeding rates to chicks, suggesting that food was not a limiting resource. Terns spent less time with their broods (more time foraging) in the 1995-96 period. However, they also had significantly larger broods and fledged more offspring. The time of each individual foraging trip decreased, suggesting that fish were easier to obtain in 1995 and 1996. Lastly, kleptoparasitism rates decreased, suggesting that the costs of foraging (time, energy) actually decreased as fewer birds adopted this strategy to compensate for what I assumed to be a lack of available food (fish). The only significant difference between the periods of 1990, 1991 and 1995, 1996 was a change in diet. Terns delivered significantly fewer rainbow smelt and more emerald shiner in 1995 and 1996. However, the average size of fish delivered did not change. Thus, there was little impact on prey captured by Common Terns in Lake Erie since the invasion of the zebra mussel.

Water quality and fish populations of the Welland River, Ontario /

The water quality and fish populations of the Welland River were observed to decline with distance downstream. This coincided with increased agricultural , domestic and industrial waste loadings. The river upstream of the City of Welland received considerable loadings from agricultural sources. Centrarchids, sciaenids, ictalurids, cyprinids and esocids characterized this upper section of the river. Most of these species were tolerant of low dissolved oxygen concentrations and the high turbidity which prevailed there . The river near Port Robinson receives many industrial and domestic wastes as evidenced by the water quality data. The fish in this section were less abundant and the observed population was comprised almost solely of cyprinids. Further downstream, near Montrose, the Welland River received shock loads of chemical wastes that exceeded a specific conductance of ISiOOO ;umhos/cm. Few fish were captured at this site and those that were captured were considered to be transients. A review of the literature revealed that none of the common indices of water quality in use today could adequately predict the observed distributions. In addition to the above, the long-term trend (l3 yrs) of water quality of the lower Welland River revealed a gradual improvement. The major factor thought to be responsible for this improvement was the operation of the Welland Sewage Treatment Plant. The construction of the New Welland Ship Canal coincided with large fluctuations of the total solids and other parameters downstream. These conditions prevailed for a maximum of three years (1972- 1975)' Furthermore, spawning times and temperatures, geographic distributions, length-weight regressions and many other descriptive aspects of the ecology of some 26 species/ taxa of fish were obtained. Several of these species are rare or new to southern Ontario.

Phytoplankton species diversity of 27 lakes and ponds of Costa Rica (Central America)

The literature on species diversity of phytoplankton of tropical lakes is scarce, and for the main part comes from studies of the big lakes in Africa, or deep lakes in South America, leaving a gap in the information about small shallow tropical lakes. In the present work the phytoplankton species composition and diversity of 27 shallow lakes and ponds in Costa Rica (Central America) was studied. The species composition was found to agree with other studies of tropical lakes, with a dominance of Chlorophyta, Cyanophyta, or in some cases Bacillariophyta or Euglenophyta; and a general paucity of Chrysophyta and Cryptophyta. Species richness varied considerably among the lakes, and tended to decrease with an increase in lake elevation. A low evenness in the species abundances was found, with one or more species outnumbering the rest by several orders of magnitude. Individual species abundances and species composition was found to vary with time in Rio Cuarto Lake, a meromictic lake situated in a region with low seasonal change in precipitation. In comparison with the phytoplankton of temperate lakes, the phytoplankton of the tropical lakes studied tended to have a lower evenness of species abundances, although species richness may be similar to temperate figures in some cases. Diversity indices sensitive to changes in the abundance of rare species tend to be higher in the tropical lakes studied; diversity indices sensitive to changes in the numbers of abundant species tend to be similar between the temperate and tropical lakes examined.

Letter to S.D. Woodruff from William Leary, steward, endorsing G. Fish to paint the new building

Letter to S.D. Woodruff from William Leary, steward, endorsing G. Fish to paint the new building (1 ½ pages, handwritten), June 7, 1875.