EFFECTS OF AXIAL COMPRESSION ON DRY ACTIVE SACCHAROMYCES CEREVISIAE STRUCTURE
Special Symposium - Innovations in Food Technology (LMC Congress)
White BioTech & Related Processes (Food-2b)
Keywords: yeast, texturometry, scanning electron microscopy
In this work, an experimental strain of dry live yeast Saccharomyces cerevisiae agglomerated in spheres with diameters between 1000 and 2000µm was considered. The mechanical resistance of these spheres was studied with uniaxial compression tests (from 0 to 4000N) by using a texturometer. Effects of mechanical constraints on the structure of yeast spheres were described using binocular and electron scanning microscopy.
It was shown that the mechanical resistance of the spheres depended on their diameter and bulk density. Indeed, a clear fracture of the spheres with a diameter higher than 1600µm and a low bulk density (749g/l in average) was observed at 1000N. In contrast, no clear structural modification of the spheres with a lower diameter was seen with compression forces from 0 to 4000N. The observation of the structure of the different spheres using scanning electron microscopy showed an air-filled area in the spheres with a diameter higher than 1600µm. This empty space was responsible for the collapse of their structure. A decrease in spheres diameter (<1600µm) related to an increase in bulk density could improve the mechanical resistance of such yeast spheres.
Presented Wednesday 19, 17:20 to 17:25, in session White BioTech & Related Processes (Food-2b).
