Functionality and yield of pectin extracted from Palmyra palm (Borassus aethiopum Mart) fruit

- Pectin yields from Palmyra palm range from 682 to 880 g kg−1 and are comparable to citrus and apple pectin yields.
- Pectin extraction is influenced by temperature, pH and time.
- Palmyra palm pectin has high degree of esterification and strong gelling potential.
- Palmyra palm pectin has about 41 g kg−1 protein and emulsifying activity.

Large numbers of fruits from Palmyra palm (Borassus aethiopum Mart), a common, native tree of tropical regions, are underutilized and left to spoil. This work was conducted to assess pectin content of Palmyra palm fruit, and to develop a reliable protocol for pectin extraction. Yield and galacturonic acid content of Palmyra palm fruit soluble solids were investigated at various pH (natural pH of 5.2-5.5, 2.5, 7), time (30-120 min) and temperature (70 °C, 80 °C, 90 °C). Yield and galacturonic acid content of extracted soluble solids were strongly dependent (p < 0.0001) on temperature, time and pH of extraction and ranged from 47 to 149 g kg−1 and 682 to 880 g kg−1 dry weight, respectively. High galacturonic acid (808-852 g kg−1) were obtained at 70 °C and 90 °C under natural pH; at 70 °C pH 7 and pH 2.5 at all temperatures studied. Analysis of pectin extracted at natural pH (30 min, 90 °C) revealed highly esterified pectin with good gelling and emulsifying properties. Production of galacturonic acid of more than 650 g kg−1 dry weight indicates that Palmyra palm fruit could serve as an excellent raw material for industrial pectin production.