PREDICTION OF MASS OF RESIDUES ON FOOD-CONTACT SURFACES FROM EDIBLE OILS AND THEIR EMULSIONS

The aim of this study was to predict the mass of fluid food residues r emaining adhered to a solid food-contact surface after drainage flow. The measurement method used simulated the drainage occurring on equipm ent surfaces in the industry, or the flow from a food package when the consumer empties it. Using Newtonian edible oils and power-law food e mulsions, and solely fluid mechanical equation derived from the fluid film flow rate expression did not predict residual mass accurately. Th erefore, correcting factors were introduced, based on experimental obs ervations, taking into account solid surface properties (surface energ y, hydrophilicity, roughness). Edible oils and food emulsions led to t wo different surface energetic correcting factors, based on the same p henomena, which improved greatly the fit between prediction and experi mental measurements. The conclusion was that, for these types of food products, surface hydrophilic character and surface tension were more important than surface roughness in governing adhered mass. (C) 1998 E lsevier Science Limited. All rights reserved.