Effect of packing media on the oxidation of canned tuna lipids. Antioxidant effectiveness of extra virgin olive oil

8 páginas, 4 tablas, 2 figuras

The effectiveness of packing media differing in the content of natural antioxidants has been tested on lipid oxidation occurring during tuna canning. Extra virgin olive oil, having a high content in natural polyphenols, and other filling media lacking phenols (refined olive oil, refined soybean oil, and brine) were selected. The three oils also showed different quantities of tocopherols, the highest amount being detected in refined soybean oil. Different rates of oxidation were observed among the four media after thermal processing and storage of tuna cans; extra virgin olive oil showed a potential antioxidant activity on fish lipids. The verified antioxidant ability may be attributed to the solubilization of hydrophilic phenols into the water−muscle interface. The phenolic composition from extra virgin olive oil studied by reversed-phase HPLC showed a marked change after fish processing, thus suggesting phenol decompositions and strong interactions between oil phenols and fish muscle components. The aqueous environment built by brine made fish lipids more prone to oxidation, presumably due to the accumulation of unsaturated fatty acids at the oil−water interface.

We acknowledge financial support for Research Project XUGA 402 01B93 provided by Xunta de Galicia and Integrated Action HI94-074 provided by the Ministerio de Educacion y Ciencia (Spain) and Ministero dell’Universita e della Ricerca Scientifica (Italy).

Peer reviewed