No abstract

Liquid food production often involves continuous processing. This leads to problems in traceability systems due to mixing zones and therefore indistinct batch identities causing difficulties with regard to withdrawals or recalls. This article outlines the possible use of the concept of dynamic simulation to improve the handling of batch identities in continuous production of liquid food, a concept we call fuzzy traceability. The concept is illustrated with a realistic example from a real dairy process line.

No abstract

Object-oriented heat-exchanger models were developed to simulate the dynamic thermal effects of dynamic changes in fluid composition and thus of fluid properties in a type of liquid typical for food products. The models were written in the object-oriented language Modelica as objects in a library structure being developed to simulate complex liquid food process lines and their control systems. The models were based on moderate discretization of the heat exchanger into control volumes, and the fluid dispersion was modelled either as ideal mixing or as transport delay in each control volume. The transport delay model exhibited the best computational performance as well as affording flexibility in fluid dispersion modelling. KeywordsAxial spatial coordinate (along the fluid channel), m or exponent in Equation (2) y Spatial coordinate perpendicular to x and z, m or exponent in Equation (2) z Vertical spatial coordinate, m or exponent in Equation (2) Greek lettersDispersive thermal conductivity due to flow dispersion defined by