Title: Transfer of sensory methodology to artisanal fisheries by development and application of quality index method (QIM)

Author(s): Ritha John Mlingi
Final project
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Supervisors: Kolbrun Sveinsdottir
Redfish; Herring; Sensory evaluation; Quality Index Method; Shelf life.


The aim of this project was to learn how sensory evaluation may be applied in Tanzanian fisheries through the development and application of quality index method (QIM) scheme for thawed red fish fillets and pre-observation of sensory changes in whole thawed herring. After thawing, both redfish fillets and whole herring were stored in cold room at 1.7±1.5 °C up to 14 and 18 days respectively. A QIM scheme for thawed redfish fillets to evaluate shelf life was proposed. A strong correlation between the Quality Index (QI) and storage time was found. The calculated QI increased linearly with storage time at 1.7±1.5 °C (QI= 0.5444 x (days in cold storage) + 2.907, R² = 0.8156). Generic descriptive analysis (GDA), total viable counts (TVC) and counts of H2S-producing bacteria were done on redfish fillets only. The maximum storage time of thawed redfish fillets stored at 1.7±1.5 °C was estimated 9 days based on GDA, TVC H2S-producing bacteria counts. A draft QIM scheme for thawed whole herring was proposed. The knowledge and experience obtained from the project would be implemented in Tanzanian fisheries as QIM methodology is a good basis for the training of fisheries professionals.

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