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Efecto de la localidad de cultivo y de la ausencia del clorénquima en las características de los polvos de nopal (Opuntia ficus-indica) / Effect of crop location and the absence of cladode chlorenchyma on the characteristics of nopal powders (Opuntia ficus-indica)Espinoza Piombo, Karina Andrea January 2012 (has links)
Memoria para optar al Título Profesional de Ingeniero Agrónomo
Mención Agroindustria / No autorizado por el autor para ser publicada a texto completo / El objetivo de este trabajo fue evaluar el efecto de la zona de cultivo y de la exclusión de la
epidermis/clorénquima (E/C) sobre algunas características químicas, físicas y tecnológicas
de los polvos de nopal. Para ello se utilizaron cladodios de tuna de 2 a 3 años de edad
provenientes de dos zonas de cultivo: Til-Til (RM) y Las Cardas (IV Región) y dos
tratamientos de preparación. El primero de ellos consistió en obtener paletas de tuna sin
pelar, mientras que en el segundo tratamiento se realizó un pelado manual eliminando toda
la capa externa de cutina, espinas, epidermis y clorénquima de las paletas dejando sólo la
parte interna y blanca, denominada médula. Los resultados se analizaron mediante
ANDEVA. Al existir diferencias significativas entre los tratamientos se aplicó la prueba de
Rangos Múltiples de Duncan a un nivel de significancia del 5%.
Los polvos de cladodios con E/C provenientes de la localidad de Las Cardas obtuvieron el
mayor contenido de cenizas (10,04%) y de fibra cruda (7,57%). El mayor rendimiento
(11,72%) e intensidad de color verde (a* entre -10,09 y -11,54) se registró en polvos con
E/C. En cuanto al contenido de humedad, no se encontraron diferencias significativas en el
factor E/C. La aw osciló entre 0,49 y 0,55, siendo mayor para los polvos sin E/C.
El contenido de fibra dietética total (FDT) e insoluble (FDI) fue mayor en polvos de
cladodios con E/C. El contenido de FDT osciló entre 54,61% y 63,05%, para polvos de
cladodios de Til- Til y Las Cardas, respectivamente; mientras que el contenido de fibra
dietética soluble fue mayor en polvos de cladodios sin E/C de Til-Til (12,63%).
El contenido de fenoles para polvos de nopal, fluctuó entre 8,92 mg EAG/g m.s. y 12,71
mg EAG/g m.s. en polvos sin y con E/C, respectivamente. La mayor actividad antioxidante
se registró en polvos de nopal sin E/C.
Respecto a las propiedades y características tecnológicas, los polvos de cladodios sin E/C
de la localidad de Las Cardas, presentaron una mayor capacidad de retención de agua (5,76
g/g), una mayor capacidad de intercambio catiónico (1,15 meq H+/g) y una menor
capacidad de absorción de aceite (2,48 g/g). La capacidad de adsorción de agua y densidad
aparente fue mayor para polvos con E/C, mientras que en la capacidad de hinchamiento no
se encontraron diferencias significativas en el factor E/C.
Finalmente se llevó a cabo una evaluación sensorial en donde los polvos con E/C resultaron
tener alto aroma herbáceo y color verde. / The objective of this study was to evaluate the effect of growing area and the exclusion of
the epidermis/chlorenchyma (E/C) on some chemical, physical and technological
characteristics of nopal powders. Nopal cladodes of 2 to 3 years old from two growth areas:
Til-Til (MR) and Las Cardas (IV Region) were used and two treatments of preparation
were applied. The first one of them consisted of cactus paddles without previous peeled,
while in the second treatment a manual peeled was realized eliminating all the outer layer
of cutin, thorns, epidermis and the chlorenchyma of paddles, leaving only the white and
inner part called medulla. The results were analysed by ANOVA and Duncan’s Multiple
Range test was applied at a 5% level of significance to detect differences among means.
Cladodes powders with E/C from Las Cardas obtained the highest ash content (10.04%)
and crude fiber (7.57%). The highest yield (1.72%) and intensity of green color (a* entre -
10.09 y -11.54) it was obtained in powders with E/C. As the moisture content in nopal
powders, were not found significant differences in the factor E/C. The aw ranged between
0.49 and 0.55 being major for the powders without E/C.
The total dietary fiber (TDF) and insoluble fiber (IDF) was higher in cladodes powders
with E/C. The FDT content ranged between 54.61% and 63.05% for cladodes powders
from Til-Til and Las Cardas respectively; whereas the soluble dietary fiber was higher in
Til-Til's cladodes powders without E/C (12.63%).
The total phenolic content ranged between 8.92 mg EAG/ g d.m. and 12.71 mg EAG/ g
d.m. in nopal powders. The highest antioxidant activity was recorded on nopal powder
without E/C.
The cladodes powders without E/C from Las Cardas, obtained a higher water retention
capacity (5.76 g/g), a higher cation exchange capacity (1.15 meq H+/g ) and a lower fat
absorption capacity (2.48 g/g). The water adsorption capacity and the apparent density were
higher for nopal powders with E/C, while in the swelling capacity no significant differences
were found.
A sensory evaluation was realized, showing the powders with E/C a high herbaceous
aroma and green color.
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Pesquisa de Vibrio parahaemolyticus em atum (Thunnus spp) comercializado na zona sul do município de São Paulo ? SP / Study of Vibrio parahaemolyticus in tuna (Thunnus spp) traded in the south region of the city of São Paulo ? SP.Juliana Chen 01 October 2004 (has links)
Com o objetivo de avaliar a presença de Vibrio parahaemolyticus em atum, foram coletadas 112 amostras, sendo 56 durante o inverno de 2003 (junho a julho) e 56, durante o verão de 2003-2004 (dezembro a janeiro), vendidos em diversos pontos comerciais da zona sul da cidade de São Paulo. Foi determinado o Número Mais Provável (NMP) de Vibrio parahaemolyticus, comparando a contaminação observada durante os dois períodos. As cepas foram estudadas quanto à produção de urease, ao fenômeno de Kanagawa e à sensibilidade a antibióticos. Apenas 2,68% das amostras foram positivas (3/112). Dessas, duas amostras foram coletadas no verão e uma, no inverno. A amostra positiva obtida no inverno apresentou 3 NMP/g, as outras duas, coletadas durante o verão, apresentaram respectivamente, 3 e 4 NMP/g. Todas as cepas isoladas de Vibrio parahaemolyticus foram negativas ao teste de Kanagawa e não produtoras de Urease, não apresentando nenhuma característica patogênica. Todas as cepas foram resistentes a ampicilina, eritromicina, estreptomicina penicilina G, polimixina B e vancomicina. Apresentaram susceptibilidade intermediária a ciprofloxacina, kanamicina e gentamicina, e sensibilidade a ácido nalixídico, cloranfenicol e tetraciclina. Conclui-se que, nas condições desse estudo, o sashimi de atum revelou-se um alimento de baixo risco ao consumidor, no que se refere a infecção (toxigênica) por Vibrio parahaemolyticus / In order to evaluate the presence of Vibrio parahaemolyticus in tuna traded in retail stores in the south region of the city of São Paulo, 112 samples were collected, 56 during the winter of 2003 (June and July) and 56, during the summer of 2003-2004 (December to January). Most probable number (MPN) of Vibrio parahaemolyticus was determined, comparing the contamination level observed in the two periods. Strains were analyzed in relation to urease production, Kanagawa phenomenon and sensitivity to antibiotics. Only 2.68% of the samples were positive (3/112), two of them collected in the summer, and one of them, in the winter. The positive sample obtained in the winter presented 3 NMP/g, and the other two samples, collected in the summer, presented 3 and 4 NMP/g, respectively. All Vibrio parahaemolyticus samples isolated were Kanagawa, urease negative. Therefore, they did not present any pathogenic characteristic. All strains were resistant to ampicillin, erythromycin, streptomycin, penicillin G, polymyxin B and vancomycin. They presented intermediate susceptibility to ciprofloxacin, kanamycin and gentamicin, and sensitivity to nalidixic acid, chloramphenicol and tetracycline. It may be concluded that, in the conditions of this study, tuna sashimi is considered low risk food in relation to toxigenic infection by Vibrio parahaemolyticus
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Caracterización de la microbiota en la producción de un vinagre tipo balsámico de tuna púrpuraAhumada Albornoz, Rodrigo Andrés January 2012 (has links)
Tesis presentada para optar al Grado de Magíster en Ciencias Agropecuarias, Mención
Producción Agroindustrial y al Título de Ingeniero Agrónomo / Tesis no autorizada por el autor para estar disponible el texto completo en línea / La utilización de nuevas materias primas para la elaboración de productos y la búsqueda
constante de alternativas para su consumo, hace que la fabricación de condimentos
alimentarios o vinagres representen una opción y la base para nuevos productos de calidad. A
pesar de la relevancia actual del vinagre, hay pocas investigaciones con respecto al vinagre de
tuna. El interés de las bacterias acéticas es cada vez mayor en la elaboración de un vinagre. Las
bacterias acéticas pueden aportar un carácter particular al producto final y mediante técnicas
moleculares se pueden identificar y así asociar a atributos organolépticos del vinagre.
El objetivo principal de esta investigación, fue caracterizar la microbiota de un vinagre tipo
balsámico de tuna púrpura obtenido con diversos inóculos y determinar las características
organolépticas otorgadas por estos, durante la acetificación.
El jugo de tuna, se concentró a 20°Brix y se fermentó con levaduras vínicas (Saccharomyces
cereviceae) durante 5 días, luego se detuvo a los 9°GL mediante un golpe de frío, deteniendo la
actividad de las levaduras. Posteriormente el mosto alcohólico de tuna se acetificó con tres
diferentes inóculos: de tuna, de vino y de una cepa acética. Una vez finalizada la acetificación
se realizaron análisis físicos, químicos y sensoriales, además de identificación molecular.
La identificación se realizó mediante técnicas moleculares a nivel de especie (PCR-RFLP 16S
rRNA). Las especies identificadas en los inóculos de tuna y vino fueron Gluconacetobacter hansenii
y Acetobacter cerevisiae, respectivamente, las cuales predominaron durante todo el proceso de
acetificación.
Sensorialmente, los tratamientos no presentaron diferencias significativas, sin embargo, existe
una leve tendencia a la preferencia de los vinagres balsámicos obtenidos con los inóculos de
tuna y vino.
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Contribution towards the development of a management plan for the baitboat and sport fishery for tuna in South AfricaNewcombe, Hylton Cecil January 2012 (has links)
Tuna are of significant global economic importance and a prime food source. Increased levels of fishing have resulted in many stocks being under threat and a number of species are considered to be overfished. The South African tuna industry has had limited management attention from the South African fisheries management agency. A recent development has been an increase in the number of tuna caught by small vessels that target the fresh tuna market in South Africa and overseas. This has highlighted the importance of developing a holistic management plan for the sector and creating an awareness, among vessel owners, of the importance of compliance with initiatives such as the Marine Stewardship Council (MSC). The South African tuna fishery comprises three sectors: baitboat, sport and longline, all of which are currently in need of acquiring more biological and fisheries data. This project was initiated to collate existing information and to collect additional information where possible. This encompassed a qualitative and quantitative assessment of the size and shape of the tuna fishing industry, which included estimates of total catch, effort, catch-per-unit-of-effort (CPUE) and stock structure (obtained through comparative estimates of age and growth), as well as socio-economic and economic information. A technique involving an examination of specific vertebrae was used to obtain age-growth information for T. albacares. These data were used to estimate von Bertalanffy (VBGF) growth parameters: F 2 1. , k 0.1 , and t₀ -0. 1 year. No significant differences in growth parameters were found in yellowfin tuna (Thunnus albacares) from different localities around the South African coast, i.e. from the south eastern Atlantic and the south western Indian Ocean. In addition, growth did not differ between South Africa and other regions (Draganic and Pelzcarski 1984, Fonteneau 1980, Gascuel et al. 1992, LeGuen and Sakagawa 1973, Lehodey and Leroy 1999, Lessa and Duarte-Neto 2004, Shuford et al. 2007, Stequert et al. 1996, Wild 1986, Yang et al. 1969). Further substantiation of the above-mentioned observations was found by recording differences in the sizes of fish caught in the inshore (baitboat and sport fishery vessels) and offshore (large pelagic longline vessels) sectors of South African tuna fisheries. A significant difference between the regions — in terms of the size of fish caught inshore — was noted, with mostly-juvenile fish being caught in KwaZulu-Natal (5.4 ± 3.5kg), sub-adult fish in the Eastern Cape (26.2 ± 13.4kg), and adult fish in the Western Cape (42.3 ± 14.4kg). Since mostly-adult fish were caught offshore by longliners, with no significant differences between regions, it is however possible th at adult fish predominantly inhabit the offshore region. Yellowfin tuna caught by the large pelagic longline fishery in the three managerial zones (A, B and C) were predominantly adult fish of similar size, namely Zone A: 38.9 ± 6.9kg; Zone B: 28.7 ± 4.6kg, and Zone C: 36.0 ± 5.1kg. The recreational ski boat sport fishery has remained stable, in terms of participation, consisting mostly of white middle aged males in the top 25% of household income distribution, having either permanent occupational status or being retired. Fishers within this sector are willing to incur great expense to partake in the fishery and they provide an important economic contribution to coastal towns, particularly in the Eastern Cape. The total catch (of 83t) of yellowfin tuna by the competitive sport fishery within the Western and Eastern Cape regions was considerably lower than that of commercial tuna baitboat catches, which amounted to 186t, and the large pelagic longline sector that caught t in 200. It is however likely that the competitive sport fishery's total yellowfin tuna catch (of 83t in 2009) of the Eastern and Western Cape competitive sport fishery was considerably less than the total yellowfin tuna catches of the whole South African deep-sea sport fishery. Longfin tuna are the primary target species of South Africa‘s baitboat fisheries, comprising an average of 86% of the total catch and generating ZAR49 million in employment income in 2002. South Africa was responsible for 20% of the total longfin tuna annual yield in 2004 in the southern Atlantic Ocean, behind Taiwan with 59%. However, yellowfin tuna only contributes a small percentage towards total catches (8.4 ± 8.2% between 1995 and 2009), generating ZAR1.3 million in employment income in 2002. Of the four vessel categories comprising the tuna baitboat fishery, ski boats had the highest yellowfin tuna CPUE in 2009 (117 ± 62 kg.vessel⁻¹.day⁻¹) and the lowest effort. The ski boats sector is the most opportunistic fishery as they are only active when either longfin or yellowfin tuna are in high abundance. At such times catches are guaranteed, so can be expected to offset expenses. In 2009 the CPUE for yellowfin tuna for 15–19m vessels and freezer deckboats was 12 ± 20kg.vessel⁻¹.day⁻¹ and 3 ± 6kg.vessel⁻¹.day⁻¹, respectively. These vessels specifically target longfin tuna when they are in abundance. Since the start of the tuna baitboat fishery in 1995, there has been a substantial increase in the number of new entrants. In 2002 this sector had a fleet size of 82 vessels with a capital value of ZAR163 million and a total employment income of ZAR58 million, employing 2 173 fishers, of which 87% were black African. The commercial tuna baitboat fleet has subsequently grown to 200 vessels and 3600 crew, with 110 active vessels fishing for a combined fleet average of 46 days per year. There are a high number of owner-operated vessels. Since 2007 the fishery's profit to cost ratio has been low due to the low abundance of tuna stocks off the coast of South Africa, which has resulted in poor catch returns, placing economic pressure on the fishery. The baitboat industry is a low-profit-margin fishery with a total net catch value worth ZAR90 million in 2009 (Feike 2010). The abundance of yellowfin tuna influences profit margins, with very high profits being made when abundance and catches are high. The large pelagic longline fishery has a total allowable effort of 43 vessels of which only 30 vessels fished during 2009, when a reported 766t of yellowfin tuna were caught, representing a total tonnage far in excess of that obtained by the combined effort of the baitboat and sport fishery. It is, however, assumed that considerable underreporting of catches takes place within this fishery, which means that the estimated total net catch value of ZAR100 million could, in fact, be much higher. Such underreporting of catches is of great concern for this fishery, as is the high bycatch of Chondricthians spp. that significantly outweighs imposed regulatory limits (DEAT 2007). The present study demonstrates the current lack of comprehensive catch and effort data for the sport, baitboat and longline fisheries as well as the serious limitations and flaws associated with current databases. Results from the present study have drawn attention to a number of high-priority research needs, as outlined below. (1) A major lack of comprehensive catch and effort data for the sport fishery, which can be rectified by focussing on obtaining more competition data, as well as high-quality catch and effort and socio-economic information, as opposed to relying on information from non-club anglers (Gartside et al. 1999, Williams 2003, Cass-Calay 2008). Acquisition of such data is relatively inexpensive: the location of organized clubs and their frequent competition meetings provide widespread coverage along the Southern African coastline. Such data acquisition efforts have the potential to provide reliable information on spatial catch trends. (2) Validation of vessel catch return data is required for commercial fisheries and on some recent data that has emerged from studies of catch rates and trends for target species, particularly in the longline fishery. In this context it should be noted that the most recent peer-reviewed publications on this exploratory fishery were published more than a decade ago (Kroese 1999, Penny and Griffiths 1999). Additional studies need to be undertaken and journal articles published on the current stock status of South African catches of yellowfin and bigeye tuna and swordfish.
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Modélisation globale et régionale de la dynamique de population du thon obèse de l'océan Indien avec le modèle SEAPODYM / Modelling global and regional population dynamics of Indian ocean bigeye tuna using SEAPODYMWibawa, Teja Arief 17 March 2017 (has links)
La pêche au thon indonésienne a souffert d'un problème de gestion dû à des statistiques de pêche incomplètes et peu fiabilité, ce qui entraîne un manque de compréhension de la dynamique des populations de thonidés de la région. Le gouvernement de l'Indonésie a lancé un programme de développement de l'infrastructure pour l'océanographie spatiale (INDESO) afin d'aider à la gestion et au suivi des ressources marines du pays. Une application du projet concerne les pêcheries thonières avec l'objectif ambitieux de modéliser en temps réel et avec des prévisions de quelques jours les distributions et abondances de trois espèces de thonidés: thon obèse, albacore et bonite. Le modèle utilisé est SEAPODYM (modèle spatial d'écosystème et de dynamique de population). La présente thèse traite uniquement du thon obèse et a trois objectifs majeurs: la préparation d'un ensemble de données de pêche géoréférencées, la production de conditions initiales pour la configuration du modèle régional INDESO et la simulation de la dynamique régionale des populations. L'ensemble de données sur les captures et les efforts de pêche géoréférencés du thon obèse de l'océan Indien a été standardisé selon cinq procédures: standardisation de la résolution spatiale, conversion et standardisation des unités de capture et d'effort, recalage des captures géo-référencées au niveau des captures nominales, et détection des principaux changements de capturabilité sur de longues séries temporelles de données sur la pêche.. L'ensemble de données de prises géoréférencées standardisées couvre les deux tiers de la capture nominale totale en raison du manque de références géographiques pour plusieurs flottilles de pêche. Le modèle régional a été configuré en trois étapes: paramétrage du modèle à résolution grossière sur une longue période historique, " downscaling " et paramétrage de la configuration globale opérationnelle et " downscaling " vers le modèle régional opérationnel. La première étape a permis de paramétrer le modèle sur le Pacifique puis l'Océan Indien sur une période de trente-neuf ans à une résolution mensuelle de 2°, permettant d'établir les conditions initiales de la population pour la deuxième configuration, à partir de 1998 et à une résolution hebdomadaire 1/4°. Cette deuxième configuration du modèle a nécessité une méthode de " downscaling " pour réviser le paramétrage et obtenir la même solution malgré quelques différences dans le forçage physique. Ce modèle opérationnel global a ensuite fourni des conditions initiales de la population et des conditions aux frontières ouvertes pour les flux de poissons traversant les frontières régionales du modèle INDESO (1/12 ° de résolution quotidienne). L'ensemble des données de pêche standardisées dans l'océan Indien a été utilisé pour inclure la mortalité par pêche et valider l'optimisation réalisée dans l'océan Pacifique. Les résultats des simulations de modèles suggèrent que le thon obèse est distribué en concentration plus élevée dans l'océan Indien Nord (au nord de 20 °S), avec une extension à travers le canal du Mozambique et le long d'un prolongement vers l'est entre 35 ° et 40 ° S. Les configurations du modèle opérationnel (mondial et régional) utilisent la production primaire nette (VGPM) et la profondeur euphotique dérivées des données satellitaires, ainsi que les cartes mensuelles climatologiques de l'oxygène dissous provenant de l'Atlas Mondial des Océans (WOA) comme forçages biogéochimiques. Une simulation régionale utilisant le modèle INDESO biogéochimique PISCES comme forçage alternatif aux produits dérivés des satellites a été testée. Les résultats préliminaires montrent que, une fois la production primaire PISCES ajustée à la valeur moyenne VGPM, les deux produits donnent des résultats similaires, ce qui suggère que des prévisions à plus long terme basées sur le modèle biogéochimique physique couplé peuvent être proposées. / The Indonesian tuna fishery has suffered from a management problem due to incomplete and less reliability of tuna data leading to lack of understanding about tuna population dynamics in its region. The government of Indonesia initiated the Infrastructure Development of Space Oceanography (INDESO) programme to support marine resource management and monitoring of the Country. One application concerns the tuna fisheries with a challenging objective of real-time and forecast modeling of three tuna species biomass distributions: bigeye, yellowfin and skipjack. The model used is SEAPODYM (Spatial Ecosystem and Population Dynamics Model). The present thesis is dealing with bigeye tuna only, and had three major objectives: the preparation of a geo-referenced fishing dataset, the production of initial conditions for the regional INDESO model configuration, and the simulation of regional population dynamics. The georeferenced fishing catch and effort dataset of the Indian Ocean bigeye tuna was standardized throughout five procedures: standardization of spatial resolution, conversion and standardization of catch and effort units, raising of geo-referenced catch to nominal catch level, screening and correction of outliers, and detection of major catchability changes over long time series of fishing data. . The standardized geo-referenced catch dataset covers two-third of total nominal catch due to lack of geographic references for several fishing fleets. The regional model was configured along three steps: the parameterization of coarse resolution model over a long historical period, the downscaling and parameterization of operational global configuration, and the downscaling to the operational regional model. The first step provided model parameterization over the Pacific and Indian Ocean for thirty-nine years period at 2° monthly resolution, allowing to establish initial conditions of the population for the second configuration starting in 1998 at resolution 1/4° weekly. This second model configuration required a downscaling method to revise the parameterization and achieve the same solution despite some differences in the physical forcing. This global operational model provided initial conditions of the population and open boundary conditions (OBCs) constraining the fluxes of fish through the regional borders of INDESO model (1/12° daily resolution). The standardized Indian Ocean fishing dataset was used for including fishing mortality and validate the optimization achieved in the Pacific Ocean. Model simulation outputs suggest that bigeye is distributed in higher concentration in the North Indian Ocean (north of 20°S), with an extension through the Mozambique Channel and along an eastward prolongation between 35° and 40°S.. The operational model configurations (global and regional) are using VGPM net primary production and euphotic depth derived from satellite data, and climatological dissolved oxygen monthly maps from the World Ocean Atlas (WOA) as biogeochemical forcings. A regional simulation using the INDESO biogeochemical PISCES model forcing as an alternative to the satellite derived products was tested. The preliminary results show that once the PISCES primary production is scaled to the VGPM mean value, both products provide similar results, suggesting that longer time scale forecast based on the coupled physical biogeochemical model can be proposed.
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Fornborg och bygd i sörmländska Rekarne under mellersta järnåldernJensen-Urstad, Kerstin January 2020 (has links)
This paper discusses the approximately twenty Middle Iron Age hillforts located in Östra and Västra Rekarne härad in Södermanland. "Härad", an administrative division, is likely to be derived from the earlier hundred division, which was based on equipping and manning ships at a time when society was hierarchical and the elite, through travel, had contact with the Roman Empire, inspiring new gods (such as Thor and Odin) to worship. The Tuna and Berga settlements are part of the hundred division but may also have played a role in organization of the earlier travels. There is a connection between Tuna and Berga and hillforts suggesting hillforts could be part of an early organization for equipping and manning ships. Some of the hillforts have house-terraces and possibly had textile production for the travels, some were possibly built for cult.
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Analysis of volatile compounds, proximate composition, and fatty acids in Pacific bluefin tuna (Thunnus orientalis)James, Cierra Alisha 07 June 2022 (has links)
Pacific bluefin tuna (PBT; Thunnus orientalis) has grown significantly in popularity in recent years due to the globalization of Japanese cuisine. PBT is highly sought after for sushi and sashimi products due to its great quality and taste. Wild populations of this species have been affected by their increasing popularity, pushing innovators in the food industry to create meat alternative versions of PBT. The muscle composition of PBT varies, leading to different types (cuts) of meat in a way that is analogous to various cuts of beef. This study evaluated the differentiation amongst the 6 distinct cuts, including otoro, ventral akami, dorsal akami, ventral chu-toro, dorsal chu-toro, and wakaremi conducting volatile analysis, proximate analysis, and fatty acid analysis. The results from these analyses can then be used as a base standard for companies seeking to create alternatives versions of PBT. Samples analyzed in this study were cultured PBT species that were caught as juveniles and raised in captivity on a PBT farm in Mexico. Volatile analysis was conducted using a SPME GC/MS method. Overall, 41 aroma compounds were identified in PBT that met the identification criteria, including 9 aldehydes, 7 alcohols, 14 alkanes, 2 ketones, 4 alkenes, 3 aromatic compounds, and 2 miscellaneous compounds. Proximate analyses were conducted using standard methods. Significant differences (p <0.05) were found between each cut for the proximate analysis. The fatty acid analysis determined that there were twenty-two identifiable fatty acids found in the different cuts. The omega-3 fatty acids eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) with DHA being present at a higher amount than EPA in each cut. Overall, there are similarities and differences among the different cuts of bluefin tuna that researchers would need to mimic to provide adequate nutritional and sensorial properties of PBT. / Master of Science in Life Sciences / Pacific bluefin tuna (PBT; Thunnus orientalis) is a fish that has gained tremendous popularity over the years due to the globalization of Japanese cuisine. This tuna species is synonymous with high quality and great taste, making it key for sushi and sashimi dishes. The increased demand for this species has caused wild populations to decrease; therefore, the food industry has sought to create meat alternatives for the species. The PBT has 6 distinct cuts that make up the composition of the fish, similar to the differences that can be found in beef cuts. These 6 distinct cuts are otoro, ventral akami, dorsal akami, ventral chu-toro, dorsal chu-toro, and wakaremi. The purpose of this study is to determine the aroma composition, fatty acid composition, and fat, moisture, ash, and protein contents of the different cuts. To measure the aroma composition, gas-chromatography mass spectroscopy (GC-MS) was used; it is a machine that can be used to identify and measure the aroma compounds of products. Standard procedures were used for the other analyses. Overall, 41 aroma compounds were identified in PBT that met the identification criteria, consisting of aldehydes, alcohols, alkanes, ketones, alkenes, aromatic compounds, and some miscellaneous compounds. The cuts displayed distinguishable differences in their fat, ash, moisture, and protein contents. The fatty acid analysis concluded that there were twenty-two identifiable fatty acids found in the different cuts. In this study, close attention was paid to omega-3 fatty acids due to their health benefits for consumers. The omega-3 fatty acids eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) were found in all cuts with DHA being present at a higher amount than EPA in each cut. From this study, researchers have the foundation for understanding the composition of PBT to create a meat alternative that meets consumer expectations.
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Dynamics of phytoplankton in relation to tuna fish farms in Boston Bay and near-shore Spencer Gulf, South AustraliaPaxinos, Rosemary, January 2007 (has links)
Thesis (Ph.D.)--Flinders University, School of Biological Sciences. / Typescript bound. Includes bibliographical references: (leaves 149-166) Also available online.
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Global sushi: A socio-ecological analysis of the Sicilian bluefin tuna fishery / Socio-ecological analysis of the Sicilian bluefin tuna fisheryLongo, Stefano B., 1969- 06 1900 (has links)
xvii, 330 p. : ill., maps. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / This dissertation is a sociological study of the Sicilian bluefin tuna fishery. It will examine the social and ecological transformation of this fishery during the modern era. This will be analyzed utilizing a sociological framework that draws on theory from environmental sociology. The Sicilian fishery has been exploited for its abundant tuna for over a millennium, providing a major source of protein for Mediterranean civilizations. However, within the last half century there has been exponential expansion of industrialized methods of production and increasing capture efforts. This has culminated in the development of bluefin tuna "ranches," which have become a highly controversial method for supplying global markets. Escalating pressure on the fishery has contributed to a host of environmental and social concerns, including pushing this important fishery to the brink of collapse. Using a combination of primary and secondary source data such as interviews with local fishers and those in the tuna ranching sector, data compiled by international agencies such as the International Commission for the Conservation of Atlantic Tunas (ICCAT) as well as archival data on the Sicilian bluefin tuna fishery, I will employ sociological methods and analyze the recent changes in social life and the environment in Sicilian fishing communities. Subsequently, this project will shed light on the globalized and industrialized nature of the modern agri-food system and lead to a better understanding of its social and environmental impacts. / Committee in charge: Richard York, Chairperson, Sociology;
John Foster, Member, Sociology;
Yvonne Braun, Member, Sociology;
Joseph Fracchia, Outside Member, Honors College
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Globalization and neoliberalism in Ecuador: The expansion and effects of the commercial tuna fishing industryBellinger, Nathan H., 1982- 03 1900 (has links)
xi, 129 p. : col. ill. / Between the 1980s and early 2000s, Ecuador's commercial tuna fishing industry evolved from an insignificant player in the global marketplace to the third largest tuna fishery in the world. The reasons behind this dramatic expansion are integrally linked to economic globalization and more specifically, the proliferation of neoliberal economic policies throughout Latin America and Ecuador. In this thesis, I link neoliberal reforms, such as increased capital mobility, free trade agreements, and export-led development, to the rapid growth of Ecuador's tuna fishery, centrally located in Manta. I then explore the place-based effects of these reforms by elucidating the social and environmental impacts of the tuna industry. I argue that while there have been some benefits, such as economic growth and job creation, expansion of Manta's tuna fishery has exacerbated local inequalities, created serious environmental problems, and led to new workplace challenges for employees in the industry. / Committee in charge: Dr. Derrick Hindery, Chairperson;
Dr. Lise Nelson, Member
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