AQUACULTURE STUDENT

KATHERINE TOZER

What They Did Back Then

* Master of Science completed 2001, University of Guelph

Advisor: Professor Y. Kakuda

Co-Advisor: Professor Richard D. Moccia

Quality improvement and shelf-life extension of fish fillets from three aquaculture species.

ABSTRACT

This thesis is an investigation of the rate of lipid oxidation in three aquaculture species. As fresh fish products are stored on ice in display counters, off-odours and flavours arise. These changes occur, in part, from the oxidation of lipids and contribute to a decrease in product palatability. By studying oxidation reactions in fresh fish, it may be possible to inhibit or slow down this degradative process thereby extending the shelf life of fish products and increase the competitiveness of the industry. The rate of oxidation was investigated using 2-thiobarbituric acid test and fluorescence. Three species of fish, rainbow trout (Oncorhynchus mykiss) , arctic charr ( Salvellnus alpinus) and tilapia (Oreochromis niloticus) were stored at three temperatures ( 10° C, 5° C and 0° C). Results showed a significant difference between species. Trout oxidize the most while tilapia did not oxidize at an appreciable rate.