High amylose starch (Gelose 80) (100 g), glycerol (30 g) and
water (35 g) were thoroughly mixed together before addition of 0,
5, 10 and 15 wt% alcohol (based on starch wt) combinations in the
feed mixture. The starch mixture was stored overnight allowing
diffusion of glycerol,water and alcohol into the starch granules. The
mixture was fed into the thermal extruder at the rate of 35 g/min.
Safety concerns for any flammable or toxic alcohol fumes present
were addressed by keeping alcohol concentrations minimal and by
continuously extracting the laboratory air. Specially designed purpose
built strong air ventilation fans were used that continuously
refreshed/replaced the lab atmosphere with clean fresh air.