Effect of microfiltration inorganic membranes on pear juice clarification and segregating microorganisms

A study was carried out about effect of microfiltration inorganic membranes(0.8 μm, 0.2 μm, 50 nm) on pear juice clarification and segregating microorganisms. The experiments were carried out by using a home-made microfiltration device. Results showed that: the impact of filtration through the three kinds of membranes was not noticeable on the physical and chemical properties (soluble solids, Vitamin C, glucose content and pH value); the efficiency of clarification through membranes of 50 nm and 0.2 μm was better than through membranes of 0.8 μm; the flavour and aroma of pear were retained more in clear pear juice clarified by 0.2 μm and 0.8 μm membranes than by 50 nm membrane. The pear juice temperature was 20～30℃ during clarification with the three kinds of membranes. The minimal permeate flux was 9.0 L/hm² during clarification with 0.2 μm membrane. 50 nm membrane was more effective to segregate microorganisms than 0.2 μm and 0.8 μm ones during clarification. General indexes of the pear juice clarified by microfiltrating through 0.2 μm membrane were better after comparing with other membranes concerning clarification quality, flavor(or aroma), permeate flux, segregating effect and so on.