Investigation of selective arabinose release from corn fibre by acid hydrolysis under mild conditions

BACKGROUND The high cost of pure arabinose has resulted in a growing demand to develop new cost‐effective methods of arabinose production from lignocellulosic and pectin‐rich materials. Corn fibre is an inexpensive by‐product of the corn wet‐milling process, and is a promising raw material for producing arabinose and other value‐added products. In this study fast dilute sulphuric acid hydrolysis of corn fibre was investigated for selective arabinose solubilization. Acid concentration and reaction time of hydrolysis of destarched ground corn fibre and raw corn fibre were 0.25–5 w/w% at 5–15 min and 0.25–1.25 w/w% at 25–75 min, respectively. Results were evaluated statistically and model equations were developed to predict the yields of sugars. RESULTS In the case of raw corn fibre the most favourable conditions were 1.1 w/w% sulphuric acid concentration and 51 min reaction time at 90°C, where a total arabinose yield of 75.9% was achieved with satisfactory selectivity. In the case of destarched ground corn fibre at a sulphuric acid concentration of 4.6 w/w%, a reaction time of 5 min and a temperature of 90°C, a total arabinose yield of 80.5% could be achieved with satisfactory selectivity, according to the model equations. CONCLUSION Arabinose‐rich liquid fractions were produced by mild sulphuric acid treatments of corn fibre. Based on the models developed the mono‐ and oligosaccharide contents of the hydrolysates can be controlled under the conditions investigated. © 2014 Society of Chemical Industry