Microbial aspects on short-time osmotic treatment of kiwifruit

In order to study the influence of solution concentration on the microbiolo gical quality of fruit after osmotic dehydration, Kiwifruit slices have bee n immersed for three hours into osmotic solutions, inoculated with Metschni kowia pulcherrima, at different concentrations (from 40 degrees to 65 degre es Brix) to obtain high moisture fruit products. Microbial adhesion kinetic to the fruit surface was studied: the number of adhering cells was affecte d by the sucrose concentration of the osmotic solution and the microbial ad hesion was strongly reduced at high sugar concentration (65 degrees Brix). Samples were packed in LDPE bags under air atmosphere and preserved at refr igeration temperature. Microbial load of inoculated and osmotically treated kiwifruit slices was determined during eighteen days of storage time. A ma thematical model based on the Zwietering modified Gompertz equation, was us ed to obtain growth parameters of the yeast and to outline the microbial ev olution of osmodehydrated Kiwifruit slices during storage. Storage data sho wed that, the microbial load was the lower, when higher the solution concen tration used for the osmotic dehydration. (C) 2001 Elsevier Science Ltd. Al l rights reserved.