Tea extracts antioxidative potential in emulsified lipid systems

Abstract

Tea leaves ( Camelia sinensis L.) extracts are source of polyphenols, i.e. anti- oxidant components. Research showed possible tea extracts use in food technology, influ- encing contained lipids stability improvement. The aim of the research was comparison of different teas extracts activity in emulsified lipid system. The present research examined different teas: white, green, yellow, oolong and black aqueous and ethanol extracts. To evaluate the most potent addition level different tea extracts concentrations were chosen. Linoleic acid oxidative stability was measured by linoleic acid conjugated dienes produc- tion monitoring. Emulsions with additives were incubated 19 hours at 37°C in darkness. Results showed different tea extracts antioxidant activity, dependent on its concentration in examined system. Highest antioxidant activity, comparable to BHT and rosemary ex- tract was found in lipid sample with addition of yellow tea ethanol extract.