Evaluation of Viscosity of Liquid Foods Using Flow Channel Instrument Modified with an Obstruction to the Flow

Abstract

A flow channel instrument as a structurally simple and easy-to-use viscometer which is used for evaluation of the viscosity of liquid foods was structurally modified with a circularly-cylindrical obstruction to the flow being fixed to the channel path. In the modified instrument, Newtonian and non-Newtonian test liquids were employed for flow experiments. The former liquid was purely viscous and the latter liquids were both of elasticities higher and lower relative to viscosity. The related flows were examined to assess the effect of the circular cylinder on the flow in consideration of the process swallowing liquid foods. The obstructed channel instrument revealed that the flow behavior differed depending on the relative elasticity of the liquid.