| || || Natasha, Janice|
| || || Post-harvest processing of farmed tilapia (Oreochromis niloticus) for potential commercialisation in Fiji|
Institution: University of the South Pacific.
Award: M.Sc. Marine Science
Subject: Tilapia -- Processing -- Fiji , Tilapia -- Economic aspects -- Fiji
Call No.: pac SH 167 .T54 N38 2014
Copyright:40-60% of this thesis may be copied without the authors written permission
Abstract: This study examines the post-harvest processing and development of value-added products from tilapia for potential commercialization of tilapia aquaculture sector in Fiji. Four prototypes of tilapia products, cold-smoked tilapia, fish fingers, surimi and fish pâté, were developed from a preceding brief market survey. The acceptances of these prototypes were evaluated by means of a Consumer Acceptance Test involving a sample population of 150 consumer panelists. Cold-smoked tilapia, fish fingers and fish pâté received very high acceptance scores (>7, like moderately). Out of the four prototypes tested, cold-smoked tilapia was the most preferred product, followed by fish fingers, fish pâté and surimi. Ninety-three percent of the sample population indicated their willingness-to-pay for these products. The acceptance, preference and willingnessto- pay for the prototypes tested were not governed by the socio-demographic characteristics of the sample population (P > 0.05). Shelf-lives of these prototypes were evaluated at two storage temperatures; 5°C (refrigerated storage) and -18°C (frozen storage); using microbiological, sensory and chemical analyses. By combining the results of microbial, sensory and chemical analyses, the recommended shelf-life for each of these products were (i) 6 weeks for vacuum-packed cold-smoked tilapia stored at 5°C and 20 weeks at -18°C (ii)15 weeks for vacuum-packed surimi at -18°C, (iii) 12 weeks for pâté in air-tight jars stored at 5°C and 20 weeks at -18°C and (iv) 20 weeks for vacuum-packed fish fingers stored at - 18°C. Storage of surimi in refrigerated condition is not recommended due its low shelflife and consumer preference. A set of preliminary work was undertaken prior to post-harvest processing of tilapia to determine the fillet yield of tilapia and bacterial load of tilapia and its respective harvest pond. Fillet yield of GIFT tilapia was 34%. Filleting generated a large amount of wastes and often considerable amount of meat was retained in the carcass, ribs and skin which could cause economic problems for potential processors. Production of tilapia with a body weight up to 700g and utilization of filleting wastes in production of tilapia feeds iv is recommended to avoid financial loss. The microbial load and presence of Enterobacteriacea of fish was significantly higher (P > 0.05) in tilapia reared at Naduruloulou Aquaculture Research Station than at Navua Prawn Farm. The high number of Enterobacteriacea in pond water and fish tissues was attributed to the use of poultry faeces for fertilization of ponds. This has implication for post-harvest quality of tilapia as contamination would lead to shorter shelf-life and production of toxins by certain pathogens. Development of good manufacturing practices (GMP) guidelines for aquaculture is recommended to minimize the likelihood of pathogens being introduced to fish and fishery production. The findings of the current study reveal that development and marketing of value-added products from tilapia may be possible given the high acceptance of these products by consumers and stable shelf-life. However, further research is recommended to determine if such value-added tilapia products can be produced in a commercial setting with the application of seafood HACCP regulations and other industry standards, accompanied by a cost-benefit analysis to determine financial feasibility.