Abstract:

In this work, arecanut seeds were used for the raw material to extract a natural red pigment by organic solvent extraction, and the stability of the pigment obtained was evaluated. Results showed that the optimum extraction process of arecanut pigment was achieved by using 70% ethanol to extract arecanut seeds for 4 h at pH 7.0 and 80 ℃ with a solid/liquid ratio of 1: 40 (g/mL). The pigment had good stability under light illumination or acidic pH value, strong reduction resistance, but poor antioxidant capacity. A hyperchromic effect of alkaline pH value and some food additives including citric acid, glucose, sodium benzoate, potassium sorbate and sodium bicarbonate on the pigment was observed. The pigment exhibited a percent loss of 13.41% when exposed to 4.0% H2O2. Some metal ions such as Na+, K+, Ca2+ and Mg2+ had little effects on the pigment and others such as Fe3+, Cu2+ and Zn2+ also had no obvious destructive effects. Characteristic color reactions preliminarily demonstrated that the pigment was one kind of anthocyanins or even flavonoids.

Key words: arecanut, pigment, extraction, stability