Preliminary Evaluation of an Optical Method for Modeling the Dilution of Fat Globules in Whey During Syneresis of Cheese Curd

An optical sensor designed to measure whey fat concentration was tested on whey samples from a cheeseprocessing plant. Whey samples were collected to determine syneresis kinetics at different times after gel cutting. Normalizedspectral sidescatter intensity was measured by mean of a fiber optic spectrometer (300-1100 nm). A sidescatter wavebandratio (S875/425) was calculated by dividing intensity at 875 by that at 425 nm. Whey fat concentrations were predicted by usingthe power low type equation previously developed by the above authors, [Fat] = .0 ln (.1 S875/425 + .2). Predicted whey fatconcentrations were compared to actual concentrations measured by the Gerber method. The change in whey fatconcentration with time after gel cutting was used to estimate the syneresis reaction rate. Results confirmed that fat dilutionin whey followed a first order response. The light sidescatter technology for determining syneresis kinetics was consideredto have potential but requires additional work to improve measurement accuracy.