Logo image
The Oxidative stability of chilled and frozen pilchards used as feed for captive Southern Bluefin Tuna
Journal article   Peer reviewed

The Oxidative stability of chilled and frozen pilchards used as feed for captive Southern Bluefin Tuna

C H Fitzgerald and H A Bremner
Journal of Aquatic Food Product Technology, Vol.7(1), pp.27-44
1998
url
https://doi.org/10.1300/J030v07n01_03View
Published Version

Abstract

Food Sciences pilchards bluefin tuna oxidation fish feeds
Freshly caught pilchards (Sardinops neopilchardus) were obtained from South Australia and subjected to chilled and frozen storage trials in order to determine their stability. The stability was gauged by visual and sensory asscssment of the raw pilchards, by sensory assessment of the odour and flavour of cooked samples and by the chemical measures of peroxide value and levels of free fatty acids. There was considerable variability in fat content between individual fish with average content over all samples analysed in the trial being about 4 to 5%. In chilled storage, the pilchards exhibited obvious deterioration within two days. Substantial peroxide values were found and oxidised odours and flavours were clearly evident after 4 days’ chilled storage. In frozen storage, oxidation occurred after only one month at a temperature of -20°C. This could bcdelayed if thc fish were glazed with water. Vacuum packaging in a film of low permeability to oxygen was less effective than glazing and is not recommended due to cost. Pilchards in which oxidation had commenced before freezing continued to oxidise in frozen storage irrespective of whether they were glazcd or vacuum packed. It was thus thoroughly demonstrated that the oil in the pilchards is very readily oxidised and careful handling, chilling, freezing and storage procedures need to be adopted to provide a product which is a nutritionally sound feed material for captive tuna. The demerit point scoring system was found to be a rapid evaluative technique useful for estimating the statc of the pilchards.

Details

Metrics

4 File views/ downloads
712 Record Views
Logo image