Characterisation of Colourant Extracted from Riped Cashew Fruits

Abstract

This study reports the extraction of colourant from ripe cashew fruits (Anacardium occidentale) using ethanol, methanol and water as solvents. The research is also to determine the constituents of the ripe cashew fruits, as well as the functional groups of the constituents. Distilled water was found to be the most suitable solvent for the extraction of the dye from the cashew fruits. Characterization of Anacardium occidentale was done using infrared and ultraviolet spectrophotoscopy. . The result reveals the type of chromophores in the active dye compound. The observed absorbance revealed the highest values at the 533.0nm for methanol, 740.0nm for ethanol and 731.5nm for distilled water. The greater volume of compounds present in the different extracts from methanol, ethanol and distilled water is derivatives of benzene and naphthalene. However, derivatives of ketone was also observed from the ethanol and methanol extract. The maximum wave length 533nm, 740.00nm and 731.50nm reveal the chromophoric groups necessary for the formation of colours {mixtures of yellowish and reddish brown}.From the spectroscopic results of the extract derivatives of ketone, benzenes and naphthalenes were evident. Other groups present include C-H, C=0, C=C, N-H, 0-H, C=C, =C-0-C, C=N, and CH_3- . It is therefore concluded from the results that anthraquinone, naphthaquinone and indigoid dyes could be present in the extract of the cashew fruit.