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Authenticity and quality of muscle foods : assessing consumer trust and fraud detection approachesSalih, Salih Mustafa January 2017 (has links)
Authenticity issues and fraudulent practices regarding animal products are affecting consumer confidence. Verifying the description, composition, processing or origin of foods can be challenging. To explore British and Kurdish consumers’ perceptions of kebab meat products, focus groups and questionnaire surveys were applied. About 40% of participants in the UK tend to purchase fewer processed meats after the European horsemeat scandal. Issues raised by participants indicated their concerns about the declaration of species, meat content, and other ingredients incorporated in kebab and other meat products. Lack of consumer trust has been linked to authenticity issues. Reactions towards the addition of fat-replacing inulin were positive by more than half of respondents. A further study aimed to investigate the effect of commercial inulin (CI) and Jerusalem artichoke (JA) tubers as fat replacers on the eating quality and overall acceptability of kebabs. Inulin flour prepared from JA by a simple protocol presented advantages with about 10% higher cooking yield and overall acceptability when compared with CI. Levels of inulin as low as 0.5% were detected in meat products using enzymatic assay, which could be relevant to detect additives and enforce labelling requirements. The authenticity (origin and species) was investigated in fish samples from commercial markets in Erbil, Kurdistan Region of Iraq (KRI). The declared fish species was checked using DNA barcoding with Cytochrome b region. A 10 % rate of mislabelling occurred only for wild common carp (Cyprinus carpio), with 9 out of 12 discovered to be the related species goldfish (Carassius auratus), which was deemed to be accidental rather than deliberate fraud. Such occurrences were from street markets and fishmongers, while none were from supermarkets. Wild and farmed common carp samples were not discriminated by DNA barcoding. Further fingerprinting using compositional profile and nearinfrared spectroscopy (NIRS) together with chemometric analysis aimed to predict composition and discriminate between wild and farmed common carp and species identity. NIRS-predictions of composition and some macrominerals of fish have a strong correlation with the references. NIRS with chemometric analysis is promising, but were not satisfactorily accurate for micro-minerals. Even with no clear solution from principal component analysis (PCA), NIRS-PCA may contribute to discriminating sample groups, but not for authentication when used alone. Having reliable techniques for authentication of food of animal origin may discourage deliberate replacement in retail, wholesale and international trade, and may contribute to reductions in food mislabelling, therefore protecting consumers from fraudulent practices.
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Hodnocení vlivu marketingové komunikace / Asssessment of marketing communication of brandVAŇKOVÁ, Veronika January 2016 (has links)
The aim of this work is to compare marketing communication of two chosen food quality brands and to analyse their influence on a selected target group. On behalf of this comparison there would be suggestions for changes influencing perception of these two brands amongst target group. The first hypothesis, which says the brand Regionální potravina is in the Southern Bohemia from chosen events to prompt sales more famous than the brand Chutná hezky. Jihočesky, was confirmed. The research also reported that responders from all these events know more the brand Regionální potravina than the brand Chutná hezky. Jihočešky, only at exhibitions and trade fairs is the brand Chutná hezky. Jihočesky known the same. The hypothesis no. 2, which says the brand Chutná hezky. Jihočesky is more famous from local media than the brand Regionální potravina, was disproved. The brand Chutná hezky. Jihočesky is better known amongst responders only from local radio and external advertisement. Through other forms of media communication such as local news, television, internet presentation and social sites got more famous the brand Regionální potravina. The third hypothesis like the second one was proved false. The awareness about the brands Regionální potravin and Chutnáhezky. Jihočesky is not equal from famer's shops and healthy food shops. The brand Regionální potravina is from these shops twice as famous amongst consumers as the brand Chutná hezky. Jihočesky. For each hypothesis were made suggestions to improve the evaluation of marketing communication for chosen food quality brands. To finish it we can say both brands are in responder's eyes known amongst consumers thanks to the marketing communication and compared with other quality brands they hold a solid position. At last it must be underlined that producers by themselves can improve the recognition of these brands mainly by labelling their appraised products and by personal presence on the sales prompting events. When a consumer meets face to face with the producer and not only with a third party that has no linkage to given products, he builds a personal relationship towards these products and this can influence the consumer's decision making process when buying.
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Youth perception of service quality of large food retailers in the Cape MetropolisAdam, Shaneen January 2017 (has links)
Thesis (MTech (Business Administration))--Cape Peninsula University of Technology, 2017. / Retailers (including food retailers) are facing challenging times due to the dynamic business environment. Increasing competition, uncertain economic environment. The sophistication of consumers has prompted retailers to improve not only their product offering but service quality too. Some food retailers, however, have gained a reputation for poor service quality. On the other hand, those food retailers providing high levels of service quality, warrant customer satisfaction and customer loyalty, and minimise customer defection, ultimately affecting positive profitability.
The youth is a significant market to target for any retailer. Retailers that can attract and muster support from the youth can build long term relationships that result in strong customer loyalty. For this study, second and third year retail students enrolled at a university of technology were deemed as the target population following the rationale that these students would be familiar with retail concepts and be conscious of service quality issues. The study aimed to measure youth perceptions of service quality of large food retailers in line with the dimensions of the Retail Service Quality Scale (RSQS). An online survey was employed via the university’s intranet to where the youth customers were requested to rate their service quality perceptions of a large food retailer they frequented the most and to highlight areas of service quality that required attention.
The results were generally neutral, large food retailers were generally perceived as fairly providing quality service in some areas, though in other areas not so successful. The findings reveal that youth significantly felt personal interaction and physical aspects of the retailer was the most important service quality determinant. In particular, convenient shopping was paramount; and thereafter quality goods and services offered by the retailer. The study further showed that youth favoured service quality offered by retailers over the price of goods and services. Therefore, youth would remain loyal to their food retailers that provide satisfactory levels of service quality even if their prices were higher than their competitors’ prices. Retailers that want to attract youth would need to improve the reliability dimension, which includes stock availability, and the service process relating to paying. The literature and the data collected provided the researcher with the opportunity to explore youth perceptions of service quality of food retailers in the Cape Metropolis.
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Variáveis fisiológicas, valor nutricional e cinética de degradação ruminal da aveia branca (Avena sativa L.) sob diferentes níveis de adubação nitrogenada.Peretti, Jaidson 09 December 2014 (has links)
Foram determinadas as variáveis fisiológicas (experimento 1) de três genótipos de aveia (Avena sativa L) e o valor nutricional e a cinética de produção de gases da cultivar IPR 126 (experimento 2), adubadas com níveis de 0, 180, 360 e 720 kg ha-1 de N. No experimento 1 avaliou-se a assimilação e a taxa de concentração intracelular de CO2, taxa fotossintética, teor de clorofila, relação folha/colmo, número de perfilhos/planta, número de folhas/perfilho, área foliar e a produção de biomassa dos três genótipos. O delineamento experimental utilizado foi o fatorial 3 x 4 (espécie e dose de nitrogênio), com três repetições, efetuando análise de variância e comparação de medias pelo teste de Duncan, ao nível de 5% de significância. Não houve diferença estatística entre as três cultivares para as variáveis analisadas, porém o tempo de corte apresentou diferença estatística, sendo que as melhores condições foram obtidas no segundo corte. No experimento 2 foram determinadas a composição química da cultivar IPR 126, assim como a estimativa dos parâmetros do modelo logístico bicompartimental para cinética de produção de gases (Vf1, Vf2, K1, K 2 e λ). O delineamento experimental foi blocos ao acaso, e utilizou-se o Critério de Informação de Akaike Corrigido (AICC) para a escolha da melhor matriz de variância e covariância. O nível de adubação causou aumento linear no teor de PB, e diminuição linear no teor de CT. O parâmetro λ variou de forma quadrática em função do nível de adubação. Os demais teores de nutrientes e parâmetros cinéticos não apresentaram variância significativa em função dos tratamentos. Não foi alcançada a fase assintótica da concentração de proteína, mesmo utilizando altas doses de nitrogênio. / We determined the physiological variables (experiment 1) of three oat genotypes (Avena sativa L) and the nutritional value and the gas production kinetics of cultivar IPR 126 (experiment 2), fertilized at levels of 0, 180, 360 and 720 kg N/ha. In experiment 1 we evaluated the assimilation and the rate of intracellular CO2 concentration, photosynthesis, chlorophyll content, leaf/stem ratio, number of tillers/plant, number of leaves/tiller, leaf area, and the production of biomass of the three genotypes. The experimental design was a factorial 3 x 4 (species and nitrogen dose), with three repetitions, performing variance analysis and comparison of means by Duncan test at 5% significance level. There was no statistical difference between the three cultivars for any variable, but cutting time showed statistical significance, and the best conditions were obtained in the second cut. In experiment 2 were determined the chemical composition of cultivar IPR 126 and the estimation parameters of the two-compartment logistic model for gas production kinetics (Vf1, Vf2, K1, K2 and λ). The experimental design was randomized blocks, and the Corrected Akaike Information Criterion (AICC) was used for choosing the best matrix of variance and covariance. The level of fertilization caused a linear increase in the CP content and linear reduction in TC content. The parameter λ varied in a quadratic pattern according to the level of fertilization. The other nutrient contents and kinetic parameters did not show significant variance in the treatments. The asymptotic phase of protein concentration was not reached, even using high doses of nitrogen.
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Variáveis fisiológicas, valor nutricional e cinética de degradação ruminal da aveia branca (Avena sativa L.) sob diferentes níveis de adubação nitrogenada.Peretti, Jaidson 09 December 2014 (has links)
Foram determinadas as variáveis fisiológicas (experimento 1) de três genótipos de aveia (Avena sativa L) e o valor nutricional e a cinética de produção de gases da cultivar IPR 126 (experimento 2), adubadas com níveis de 0, 180, 360 e 720 kg ha-1 de N. No experimento 1 avaliou-se a assimilação e a taxa de concentração intracelular de CO2, taxa fotossintética, teor de clorofila, relação folha/colmo, número de perfilhos/planta, número de folhas/perfilho, área foliar e a produção de biomassa dos três genótipos. O delineamento experimental utilizado foi o fatorial 3 x 4 (espécie e dose de nitrogênio), com três repetições, efetuando análise de variância e comparação de medias pelo teste de Duncan, ao nível de 5% de significância. Não houve diferença estatística entre as três cultivares para as variáveis analisadas, porém o tempo de corte apresentou diferença estatística, sendo que as melhores condições foram obtidas no segundo corte. No experimento 2 foram determinadas a composição química da cultivar IPR 126, assim como a estimativa dos parâmetros do modelo logístico bicompartimental para cinética de produção de gases (Vf1, Vf2, K1, K 2 e λ). O delineamento experimental foi blocos ao acaso, e utilizou-se o Critério de Informação de Akaike Corrigido (AICC) para a escolha da melhor matriz de variância e covariância. O nível de adubação causou aumento linear no teor de PB, e diminuição linear no teor de CT. O parâmetro λ variou de forma quadrática em função do nível de adubação. Os demais teores de nutrientes e parâmetros cinéticos não apresentaram variância significativa em função dos tratamentos. Não foi alcançada a fase assintótica da concentração de proteína, mesmo utilizando altas doses de nitrogênio. / We determined the physiological variables (experiment 1) of three oat genotypes (Avena sativa L) and the nutritional value and the gas production kinetics of cultivar IPR 126 (experiment 2), fertilized at levels of 0, 180, 360 and 720 kg N/ha. In experiment 1 we evaluated the assimilation and the rate of intracellular CO2 concentration, photosynthesis, chlorophyll content, leaf/stem ratio, number of tillers/plant, number of leaves/tiller, leaf area, and the production of biomass of the three genotypes. The experimental design was a factorial 3 x 4 (species and nitrogen dose), with three repetitions, performing variance analysis and comparison of means by Duncan test at 5% significance level. There was no statistical difference between the three cultivars for any variable, but cutting time showed statistical significance, and the best conditions were obtained in the second cut. In experiment 2 were determined the chemical composition of cultivar IPR 126 and the estimation parameters of the two-compartment logistic model for gas production kinetics (Vf1, Vf2, K1, K2 and λ). The experimental design was randomized blocks, and the Corrected Akaike Information Criterion (AICC) was used for choosing the best matrix of variance and covariance. The level of fertilization caused a linear increase in the CP content and linear reduction in TC content. The parameter λ varied in a quadratic pattern according to the level of fertilization. The other nutrient contents and kinetic parameters did not show significant variance in the treatments. The asymptotic phase of protein concentration was not reached, even using high doses of nitrogen.
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Relationship Marketing: A quantitative study on what factors affect customer satisfaction towards organic food.Guo, Mingyang, Sun, Jianan, Zhang, Wanting January 2018 (has links)
Background: With the development of organic food market, the marketers are required to investigate how to satisfy their customer in order to gain more profit and competitive advantages in the market. The investigation of customer satisfaction helps the researchers know the requirement of customer. Purpose: The purpose of the paper is to explain what factors affect customer satisfaction towards organic food. Methodology: The quantitative approach had been applied in this study. All the data was collected through self-completion questionnaire while SPSS has been used to analyze the data. Findings: The results indicated that price, taste and freshness can affect the customer satisfaction towards organic food while the food safety will not lead to the influence of customer satisfaction in this research
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Rastreabilidade de soja Roundup Ready® em produtos agrícolas e derivados: produção de materiais de referência e uso de marcadores AFLP / Roundup Ready® transgenic soybean traceability in agrifood products and derivatives: reference materials production and the use of AFLP markersOthon Silva Abrahão 18 March 2008 (has links)
A introdução de variedades transgênicas de soja provocou grandes alterações no mercado mundial e na legislação de países produtores e compradores, principalmente no que se refere à certificação, rastreabilidade, biossegurança e rotulagem. A soja é responsável por quase metade das receitas com exportação do Brasil, estando presente na forma de matéria-prima ou ingrediente em parte significativa dos alimentos no mercado brasileiro. O limite estabelecido de 1,0 % para presença de transgênicos em alimentos, acima do qual a rotulagem passa a ser obrigatória, gerou a demanda por materiais de referência para controle e quantificação em matérias-primas e alimentos, para harmonização e uniformização dos resultados obtidos em diferentes equipamentos e laboratórios, atualmente produzidos com exclusividade pelo Instituto de Materiais de Referência e Medidas - IRMM, na Bélgica. Diante do alto custo e da dificuldade de obtenção destes produtos, foram elaborados, utilizando-se técnica de moagem e mistura criogênica, com verificação por PCR em tempo real, candidatos a materiais de referência para soja transgênica Roundup Ready® (soja RR) em pó nas concentrações de 0%, 0,1%, 0,5%, 1,0%, 2,0% e 5% de material transgênico. Para rastrear a origem da soja transgênica, aplicou-se o método de marcadores AFLP sobre 29 variedades de soja RR, sendo 21 argentinas e 8 brasileiras, encontrando-se 6 bandas polimórficas, produtos de 4 pares de primers, selecionados de um total de 67 reações usando diferentes combinações de primers seletivos. Por este método, foram caracterizadas 15 das variedades argentinas e todas as variedades brasileiras. Para alimentos processados em análise de PCR, adotou-se a estratégia de detecção de fragmentos curtos (cerca de 100 pb) de soja RR, com desenho de primers usando programas computacionais de livre acesso na Internet (Primer3, NetPrimer, Rebase) e validação por digestão com endonucleases e sequenciamento. Foram estabelecidos dois novos conjuntos de primers para detecção e quantificação de fragmentos dos genes da lectina e CP4 EPSPS de soja RR, testados nas 29 variedades de soja RR e três matrizes de alimentos à base de soja / The introduction of soybean transgenic cultivars brought several changes in both world trade and regulation rules for producers and consumers, mainly in relation to certification, traceability, biosafety and labeling. Soybean is one of the largest commodities in the world trade and responsible for half of the Brazilian export incomings, present as raw material or ingredient in significant part of foods in the local market. The adoption of the threshold of 1,0 % for nonintentional presence of GMO in food, requiring obligatory labeling for contents above this level, demands reference materials for the control and quantification of transgenics in raw material and processed food, allowing the harmonization of results from different methods and laboratories, currently being produced exclusively by the Institute for Reference Materials and Measurements - IRMM, in Belgium. Due to the high costs and difficulty to obtain these products, candidate reference materials of Roundup Ready® transgenic soybean (RR soybean) were produced at levels of 0 %, 0,1 %, 0,5 %, 1,0 %, 2,0 % and 5,0 % of transgenic material, using cryogenic milling and mixing techniques, with subsequent verification by real time PCR. Tracing of Roundup Ready cultivars by origin was done through AFLP molecular markers in a total of 29 RR soybean cultivars: 21 Argentinean and 8 Brazilian cultivars. Fingerprinting was possible in 15 Argentinean and all Brazilian cultivars through 6 bands obtained from 4 selective pairs of primers, singled out from 67 different combinations of selective primers. For PCR analysis of processed food, primers were designed using freeware sources over the Internet (Primer3, NetPrimer, Rebase) for short fragments amplification (around 100 bp). Primers sets for the amplification of lectin and CP4 EPSPS gene fragments from RR soybean were designed for the detection of these genes in the 29 RR soybean cultivars and three soybean based food matrices, with the results validated by endonucleases digestion and sequencing
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Estudo da qualidade e comercialização da banana nos diferentes mercados públicos e feiras livres do Recife-PE.SILVA, Irislânia Barbosa da 24 May 2013 (has links)
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Previous issue date: 2013-05-24 / The study refers to the quality and marketing he fruits of banana in different Public Markets and Free Trade in Recife / PE. With the aim of characterizing the fruits of banana and identify their marketing in the research environment. The methodologies used in the research were: questionnaires for traders banana Check lists and environment observation regarding safety, hygiene and quality of the fruit. Collecting data with bibliographic research and photographic record. The research found problems of safety, hygiene and quality in the Markets and Fairs study has characterized the fruit marketed in the research environment over the appearance of the fruit, but also described the process of marketing the fruit. It turned out that the Free Markets and Fairs surveyed do not meet most of the time demands of the Health Surveillance in prérequesitos as, buildings, waste treatment, environmental disinfection and hygiene of food handlers. It was concluded from this study need to be able to turn to public need to supervise, organize, train, en order to improve all the demands that are required for those amnipula food. Regarding the marketing of banana was found that the origin of most fruits are marketed from the Forest Zone of Pernambuco. / O estudo refere-se a qualidade e comercialização de banana em diferentes Mercados Públicos e Feiras Livres em Recife/ PE. Seu objetivo é caracterizar os frutos de banana e identificar sua comercialização no ambiente de pesquisa. As metodologias empregadas na pesquisa foram: aplicação de questionários para comerciantes de banana e Check lists de observação do ambiente referente a segurança, higiene e qualidade do fruto. Coleta de dados com a pesquisa bibliografica e registro fotográfico. A pesquisa detectou problemas de segurança, higiene e qualidade nos Mercados e Feiras estudadas; foi caracterizado o fruto comercializado no ambiente de pesquisa em relação a aparencia do fruto, como também, descreveu o processo de comercialização do fruto. Detectou-se que os Mercados e Feiras Livres pesquisados não atendem na maioria das vezes as exigencias da Vigilância Sanitária em pré requesitos como, edificações, tratamento do lixo, desinfecção do ambiente, e higiene dos manipuladores. Concluiu-se com essa pesquisa a necessidade do poder publico se voltar para necessidade de fiscalizar, organizar, capacitar, en fim melhorar todas as exigências que se requer para quem manipula alimentos. Em relação a comercialização da banana detectou-se que a origem da maioria dos frutos comercializados são provenientes da Zona da Mata de Pernambuco.
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Métodos de extração e qualidade da fração lipídica. / Extraction methods and quality of the lipid fraction.Aelson Aloir Santana Brum 10 January 2005 (has links)
Um estudo crítico foi realizado utilizando quatro métodos clássicos de extração de lipídios em aveia em flocos e peito de frango. Foram comparados os rendimentos, o tempo de extração, a repetibilidade de cada método e a qualidade oxidativa da fração lipídica obtida. As metodologias utilizadas foram as de Soxhlet, com n-hexano como solvente, nos períodos de quatro e oito horas de extração; Folch et al., com clorofórmio e metanol na proporção de 2:1 (v/v); Bligh & Dyer, com clorofórmio, metanol e água na proporção de 1:2:0,8 (v/v) e Hara & Radin, com n-hexano e isopropanol, na proporção de 3:2 (v/v). Os resultados obtidos indicaram que para a aveia em flocos, os métodos de Soxhlet e Bligh & Dyer apresentaram um rendimento superior (7,71 % e 7,66 %, respectivamente) em relação ao método de Hara & Radin e Folch et al. (6,61 % e 6,93 %, respectivamente). No estudo do peito de frango, os métodos de Soxhlet, Folch et al. e Bligh & Dyer apresentaram um rendimento satisfatório de lipídios totais, sendo, respectivamente, de 1,56 %, 1,56 % e 1,65 %. Apesar do bom rendimento em lipídios totais, o método de Soxhlet afetou a qualidade da fração lipídica em ambas amostras, demonstrada pela presença de peróxidos (4,39 e 4,19 meq O2/kg no peito de frango; 3,71 e 3,70 meq O2/kg na aveia em flocos) e pela acidez oléica (2,58 % de ácidos graxos livres (AGL) no peito de frango; 2,25 e 2,24 % AGL na aveia em flocos), em ambos os períodos de tempo da extração. Com base nos resultados deste trabalho, indica-se a metodologia de Bligh & Dyer para os casos em que haja interesse em uso posterior das frações lipídicas, em detrimento da de Soxhlet, não recomendável para o fim mencionado. / A critical study was carried through with four clasical methods of extraction of lipids from chicken breast and oat flakes. The yield, the extraction time, the repeatability of each method and the oxidative quality of the lipid fraction were evaluated and compared. The methodologies evaluated were Soxhlet, with n-hexane as the solvent, in periods of four and eight hours of extraction; Folch et al., with chloroform and methanol in the ratio of 2:1 (v/v); Bligh & Dyer, with chloroform, water and methanol, in the ratio of 1:2:0.8 (v/v), and Hara & Radin, with n-hexane and isopropanol, in the ratio of 3:2 (v/v). The results indicated that for oat flakes, the methods Soxhlet and Bligh & Dyer presented higher yields in total lipids (7.71 % and 7.66 %, respectively) than the methods Hara & Radin and Folch et al. (6.61 % and 6.93 %, respectively). In the study with chicken breast, the methods Soxhlet, Folch et al. and Bligh & Dyer presented the highest yields, being respectively 1.56 %, 1.56 % and 1.65 %.Despite the good yields in total lipids, the Soxhlet method affected the quality of the lipid fraction in both samples, demonstrated by the presence of peroxides (4.39 and 4.19 meq O2/kg in chicken breast; 3.71 and 3.70 meq O2/kg in oat flakes) and by the acid values (2.58 % FFA [free fatty acids] in chicken breast for both extractions; 2.25 and 2.24 % FFA in oat flakes,) for both periods of time evaluated. Based on the results obtained in this research, the authors recommend Bligh & Dyer methodology whenever there is interest in further use of the lipid fraction and strongly disencourage Soxhlet method for the purpose mentioned.
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Spatiotemporal variability in fatty acid profiles of the copepod Calanus marshallae off the west coast of Vancouver IslandBevan, Daniel 21 April 2015 (has links)
Factors affecting energy transfer to higher trophic levels can determine the survival and
production of commercially important species and thus the success of fisheries
management regimes. Juvenile salmon experience particularly high mortality during
their early marine residence, but the root causes of this mortality remain uncertain. One
potential contributing factor is the food quality encountered at this critical time. The
nutritionally vital essential fatty acids (EFA) docosahexaenoic acid (DHA, 22:6n-3) and
eicosapentaenoic acid (EPA, 20:5n-3) are essential to all marine heterotrophs, and their
availability has the potential to affect energy transfer through a limitation-driven food
quality effect. Assessing variability in DHA and EPA in an ecologically important prey
species of juvenile salmon could give insight into the prevalence and severity of food
quality effects. On the west coast of Vancouver Island (WCVI), one such species is the
calanoid copepod Calanus marshallae. This omnivorous species possesses a high
grazing capacity and the ability to store large amounts of lipids. As it is also an important
prey item for a diverse array of predators, including juvenile Pacific salmon, C.
marshallae plays a key role in energy transfer from phytoplankton to high-trophic
iv
consumers. This study quantified spatiotemporal variability in the quality of C.
marshallae as prey for higher trophic levels using three polyunsaturated fatty acid
indicators: DHA:EPA, %EFA and PUFA:SFA (polyunsaturated fatty acids to saturated
fatty acids). Samples were collected on the WCVI in May and September of 2010 and
May 2011. The environmental parameters included in the analysis were the phase of the
Pacific Decadal Oscillation (PDO), sea surface temperature (SST), latitude, station depth,
and season (spring versus late summer). Despite a phase shift in the PDO from positive
to negative, overall means of the fatty acid indicators did not vary between May 2010 and
May 2011. Same-station %EFA values rarely fluctuated more than 5%. DHA:EPA
ratios were more variable but without a discernable pattern, while PUFA:SFA ratios
decreased in shelf stations and increased offshore. Contrary to expectations, fatty acid
indicators showed a weak positive correlation or no relationship with SST, nor was there
a relationship with latitude. The narrow temperature range observed across all stations
suggests that temperature may not play a significant role in PUFA availability off the
WCVI. There were, however, significant relationships between the fatty acid indicators
and bottom depth and season. Shelf and slope stations showed significantly higher
%EFA and PUFA:SFA than did offshore stations (depth >800 m), with this gradient
appearing stronger in May than September. While the food quality represented by C.
marshallae was consistent across all shelf stations, the lower food quality observed
offshore could potentially affect juvenile salmon growth along the WCVI where the shelf
narrows to less than 5 km. / Graduate / dpbevan@uvic.ca
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