Describing dewatering during mushroom blanching with Flory Rehner’s theory

1. Describing dewatering during mushroom blanching with Flory Rehner’s theory PhD. Student: Ekaraj Paudel Phone: +31 6 4676 4946 Thesis advisor: Prof. Dr. ir. RM Boom E-mail: ekaraj.paudel@wur.nl Supervisor: Dr. ir. RGM van der Sman URL:www.fpe.wur.nl Research group: Food Process Engineering Research school:VLAG Supported by:C4C holding Period: Sept 2011-Sept 2015 • The water holding capacity (WHC) in food science is widely used but often an ill defined and less understood term. In this study, we have quantified the WHC change of white button mushroom (Agaricusbisporus) during its blanching. The WHC change is expressed as the change in the interaction of water with the mushroom polymers and polyols, as expressed in Flory Rehner’stheory. The loss has been accounted for by the change of the Flory-Huggins interaction parameter with temperature. Method: A magnitude of centrifugal force were applied to the heat treated sample. The osmotic pressure was computed from the composition of the material. The elastic pressure was calculated from the difference of osmotic pressure and external pressure applied to the sample. Parameters in Flory Rehner’s theory were computed with the curve fitting of elastic pressure against the polymer volume fraction Theory: Swelling pressure equals to sum of osmotic pressure and elastic pressure. Under equilibrium, the swelling pressure is equal to the external pressure applied to the material. An illustration of application of centrifugal force in the mushroom sample. The bigger circle shows the external pressure gradient within the mushroom sample. Fig: The change in Flory-Huggin’sinteraction parameter of mushroom protein with the temperature Project title: ConceptualProcess Design of Mushroom Processing.