A NEW LABORATORY DRYER FOR ANALYZING THE DETERIORATION KINETICS OF BIOMATERIALS

Convective drying is a cost saving preservation technique for the prod uction of bulk products. However, heat sensitive bioproducts may be da maged by convective dying. This paper presents the conception of a con vective laboratory dyer with particular features for a simple and rapi d examination of deterioration processes during the crying of biomater ials. The dryer is described and results are given concerning the pres ervation of microorganisms for environmental applications. The results show that deterioration of the gram-negative bacteria Pseodomonas put ida during drying is mainly caused by dehydration. Membrane damage is one of the dehydration deterioration mechanisms. Drying temperatures b elow 40 degrees C ensure that thermal death of P. putida is neglegible .