Effect of Light on the Lipid Oxidation in Fish Sausage

Abstract

Effects of light on the lipid oxidation and changes in NO-heme and flavor of fish sausage were studied under various storage temperatures with two packaging films having different physical properties. Measurements of TBA value, NO-heme pigment contents, and olfactory evaluation were made with the surface portion of the sausage. The results were as follows.
1. The effect of light on the TBA value appeared more clearly at the high storage temperature of 37 °C than at 15 °C or 5 °C. It was assumed that the light itself had no direct oxidizing effect, but accelerated the oxidation when oxygen penetrated through the film at the higher temperature.
2. The effect of light on the NO-heme degradation developed earlier than on the increase in TBA value. Some possibility of an antioxidant effect of NO-heme was also suggested.
3. The effect on the lipid oxidation and NO-heme degradation was about the same for the sunlight and the fluorescent light.
4. Oxygen permeability of packaging films had more effect than light transmissivity on the NO-heme degradation and the lipid oxidation.
5. Off-odor of the sausage, apparently caused by lipid oxidation, appeared at (15 °C, 15 days) and (5 °C, 45 days) storage in light, whereas no off-odor was detected even after 60 days storage at 15 °C and 5 °C in the dark.
6. Higher correlations were observed between flavor score of sausage and NO-heme contents than between flavor score and the TBA values.