Freeze fracture electron microscopy of an aqueous solution of glycerol (10%) frozen in a straw (0.25ml capacity). Ice was nucleated within the straw at -7°C. The sample was then cooled at 10°C per minute to -100°C and then transferred to liquid nitrogen. Longitudinal fracture of the straw following by deep etching reveals the structure of ice (etched areas) and of the freeze concentrated material (non-etched material). The structure of the ice along the straw shows evidence of the longitudinal growth of ice following nucleation. Detail from a longitudinal fracture of a whole straw.
