Straw of Oilseed Rape Joins the Biofuel Sources Team

Researchers at the Institute of Food Research are looking at how to turn oilseed rape straw into biofuel.

Straw contains a combination of sugars that is a potential source of biofuels that would not compete with food production and will also be a profitable way of utilizing waste. However, pre-treatments are needed since the sugars are in an inaccessible form for conversion into biofuels.

Using the facilities at the Biorefinery Centre on the Norwich Research Park, Professor Keith Waldron and his team have been looking to unlock the sugars in the tough straw, particularly, at the pre-treatment stage. Their main focus is on steam explosion, which involves 'pressure-cooking' the biomass, to catalyze a number of chemical reactions. A rapid pressure-release then causes the material to be ripped open, to further improve accessibility. A set of combinations of temperatures and durations of steam explosion were then used and the effect of each combination is evaluated. It was found that the amount of cellulose converted to glucose increased with the severity of the pretreatment. 

In another study, scientists discovered key factors that determine the efficiency of saccharification, one of which is the uronic acid. This compound limited the effect of enzymes. The final sugar yield was found related to the removal of xylan, a component of cell walls. These findings will help improve the efficiency by which straw can be converted to biofuels.