14A-17

C. I. MORARU, Department of Food Science, Rutgers University, 65 Dudley Road, New Brunswick, NJ 08901 and G. M. Costin, Faculty of Food Industry, University "Dunarea de Jos" Galati, Str.Domneasca 47, Galati, 6200, Romania.

JUSTIFICATION: Crossflow microfiltration is the newest stabilisation technique used in brewing, and its main advantage over the classical stabilisation techniques is that it is more environmentally friendly. The use of CMF for beer stabilisation is not very wide spread at the moment, because of the dramatic decline of the flux after the first moments, caused by membrane fouling.

OBJECTIVES: For the commercial use of this operation, one should be able to estimate the flux value when designing the process. This paper aimed to estimate the flux values by studying the influence of the work parameters (crossflow velocity, transmembrane pressure and temperature) on the permeate flux.

METHODS: Beer microfiltration experiments were performed under a various combination of process parameters (cross-flow velocity, transmembrane pressure, temperature) and the experimental values of the transmembrane flux were determined. The influence of the process parameters on these values was analyzed, and these correlations were expressed in a mathematical form.

RESULTS: From the experiments performed, it was concluded that crossflow velocity is the parameter with the strongest influence on the flux value, while transmembrane pressure has a positive influence only in the initial moments and a negative influence in the steady state phase. Temperature has just a very little influence on the flux value.

SIGNIFICANCE: There have been identified some equations that can be successfully used for the prediction of the flux value in crossflow microfiltration of beer.