Chemical composition and phyto-chemical factors of sorrel seeds (<i>Hibiscus sabdariffa </i>L.) boiled at varying durations

Abstract

This study was carried out to determine the chemical composition of sorrel seeds boiled at varying durations. Cleaned sorrel seeds were poured into three (3) litres of boiled water (at 100 C) per batch of 1kg (i.e. in ratio of 3:1) at different boiling durations of 0, 15, 30 and 45 minutes, respectively. The boiled sorrel seeds were sun dried by spreading on trays until well dried. Samples of the boiled sorrel seeds were analysed for chemical composition and phyto-chemical factors. The results showed that the duration of boiling significantly (p< 0.05) affected the crude protein, crude fibre and ether extract contents. Crude protein and ether extract values increased as the duration of boiling increased from 0 to 45 minutes. The lowest crude protein (28.00%) and crude fibre (12.80%) was obtained at 30 minutes duration of boiling while their respective values 29.22% and 14.50% were obtained from 45 minutes duration. Ether extract decreased with increased boiling duration. The values of anti – nutritional factor declined with increase in the duration boiling. There was also significant differences (p<0.05) in phytic acid and tannin levels. The 45 minutes duration of boiling had the lowest value for phytic acid (0.19%), tannin (1.1%) and saponin (7.65%). It is concluded that processing of sorrel seed by boiling enhanced nutrient availability of crude protein, crude fibre and ether extract, and reduced anti-nutrients (phytic acid, tannin and saponin) to a tolerable level.

Keywords: Phyto-chemical factors; Boiling durations; Chemical composition; Sorrel seeds