a comparative study on antioxidative properties of carameled reducing sugars; inhibitory effect on lipid oxidative and sensory improvement of glucose carameled products in shrimp flesh

the aim of the present study was to compare three reducing sugars (d-glucose, d-arabinose, d-mannose) with respect to the antioxidative activity characteristics of their caramelisation products (cps) prepared by monitoring uv-absorbance, browning intensity, ferric ion reducing capacity, fe2+ ion chelating activity as well as dpph radical scavenging activity. moreover, the effect of cps from d-glucose on prevention of lipid oxidation and improvement of sensory characteristics were examined in indian shrimp flesh (penaeus indicus) during its frozen storage for a duration of 6 months. the reducing sugars were heated at 100°c at ph 10 for 100 minutes to generate cps. results revealed greater antioxidant activity of the hexoses, d-glucose and d-mannose, than that of the pentose sugar, d-arabinose, as evidenced by the higher uv-absorbance, browning development, reducing power, chelating as well as dpph radical scavenging activity. results of the chemical analysis including tbars and ffa proved that the addition of cps from glucose (g-cps) could retard the formation of compounds produced over lipid oxidation in g-cps-added shrimps (p< 0.05). more desirability in sensory attributes of the shrimps treated with g-cps was expressed than in the untreated samples during the 6 months of storage. these results reflect that g-cps can be utilized as additives in seafood with appropriate antioxidative and techno-functional properties.