Abstract
A coherent light scattering experiment on aqueous suspension of Saccharomyces cerevisia yeast with a concentration that covers five orders of magnitude was performed. The average scattered light far field was recorded using a CCD. A computer code for image processing was written for this purpose and used for providing the first order statistics of the far interference field. The variation of the average speckle size with the particle concentration was analyzed and a very fast procedure for monitoring the yeast concentration is suggested. The possibility of monitoring the fermentation process by a fast assessment of the yeast concentration is suggested, as well.