Dietary fiber and fermentability characteristics of different pili (Canarium ovatum, engl.) varieties in the Philippines

Abstract

Pili nut (Canarium ovatum Engl.) is an indigenous fruit-bearing tropical tree nut in the Philippines. This study determined the dietary fiber and in vitro fiber fermentability characteristics of the pulp and kernel of seven approved Pili nut varieties that are cultivated in single soil conditions. The Pili nut pulp is an excellent source of dietary fiber (4.18–14.5 g/ 100 g soluble fiber; 34.0–43.2 g/ 100 g insoluble fiber), while kernel contributes a considerable amount. Short-chain fatty acid (SCFA) acetic acid (0.46–0.93 mmol/g) was the organic acid detected in the Pili nut kernel, while the pulp’s major organic acids were acetic (0.59–2.49 mmol/g), butyric (0.31–1.68 mmol/g), and propionic (0.22–1.04 mmol/g) after simulating human colonic fermentation. Significant difference in SCFA concentration was observed among varieties (p < 0.05). Pili pulp total anthocyanidin ranged from 197–305 mg catechin/ 100 g. Aside from the commonly consumed Pili nut kernel, the nut pulp is a readily available source of low-cost dietary fiber and health-promoting SCFA.