Short-term germination of faba bean (Vicia faba L.) and the effect on selected chemical constituents
Xinyi Wei, Janitha P.D. Wanasundara, P.J. Shand
Abstract
Selected chemical compounds of five faba bean (FB) cultivars; Snowdrop (low tannin), Taboar (high tannin), Snowbird (low tannin), Fabelle (low vicine & convicine), and Malik (high tannin) that were grown in North America (3 production years) were determined. The effect of short-term germination (24 h, 48 h, and 72 h) on the levels of phytic acid, vicine/convicine (v/cv), oligosaccharides, and total phenolics were evaluated. On average, FB contained 2% phytic acid and there was no difference between the 5 cultivars. Fabelle presented the lowest level of v/cv of 1 and 0.4 mg/g, respectively while the others had 7.27–10.82 and 3.53–3.93 mg/g, respectively. No significant difference was found among cultivars for oligosaccharides content. Content of total phenolics differed significantly (p ≤ 0.05) between FB cultivars. Snowdrop and Snowbird had the highest total phenolic content of 48.4 and 48.3 mg/g, respectively, while Fabelle had the lowest level of 10.8 mg/g. All cultivars showed significantly (p ≤ 0.05) reduced contents of raffinose (100%), stachyose (60%), verbascose (80%) at 72 h. Germination had no significant effect on phytic acid, vicine (except Snowbird), and convicine levels. At 48-h, Snowdrop and Snowbird seeds only showed 17-18% reduction (p ≤ 0.05) in total phenolic content. Germination between 48 to 72 h is an option to produce FB seeds with very low levels of oligosaccharides.