Main content area

Changes in the cell wall polysaccharides during storage and hardening of beans

Shiga, Tânia M., Lajolo, Franco M., Filisetti, Tullia M.C.C.
Food chemistry 2004 v.84 no.1 pp. 53-64
arabinans, arabinose, beans, cell walls, cooking, cotyledons, glucose, methylation, polymers, rhamnose, sodium hydroxide, viability, water solubility, xyloglucans, xylose
Experiments were carried out to study the changes induced by HTC development in the cell wall polymer sugar composition of beans stored under three different conditions. The cotyledon cell wall polysaccharide was composed, to a large extent, of Ara-rich polymers, released by hot-water, CDTA and NaOH. Cell wall polymers contained medium amounts of GalA, Xyl, Glc and minor amounts of rhamnose. The methylation analysis showed the presence of high amounts of terminal arabinose and 5-linked arabinose, and intermediate amounts of 2,5- and 3,5-linked arabinose probably derived from branched arabinans. Small amounts of terminal xylose, 2-linked xylose and 4,6-linked glucose indicated the presence of xyloglucan. There was an inverse relationship between loss of seed viability and increase in cooking time. Hard beans showed reduction of cell wall polysaccharide water-solubility. Beans stored under accelerated condition, mainly showed loss of uronic acid in the water-soluble polymer fractions. Mild storage condition, mainly induced increase of Ara-rich polysaccharide contents in the water-insoluble polymer fractions. Storage at 4 °C proved to be the best condition, since it prevents HTC development.