Development of New Type Clarified Apple Juice Containing Partially Enzymatic Degraded Pectin through Ceramic MF Membrane

We developed a new type apple juice containing partially enzymatic degraded pectin which is clarified through ceramic MF membrane, since the apple pectin is considered as a functional material being good for human health. The molecular weight of water soluble pectin (WSP) in original apple juice was approximately distributed in 20000 to 3000000. The higher molecular weight WSP in original juice showed the lower permeability through the MF membrane. It was considered that higher molecular weight WSP formed a fouling layer of a self-rejection type dynamic membrane on the MF membrane and inhibited the permeation of WSP. Permeability of WSP on filtrating to volume reduction factor (VRF) 2.5was only 5.7% on a basis of concentration. Therefore, higher molecular weight WSP was partially degraded by a pectic enzyme, of which molecularweight over 1000000 disappeared by the treatment at 20℃ for 5 min. The permeability of WSP on filtrationg to VRF 2.5 was largely improved to 55% on a basis of concentration by this treatment. The procipitation of pectin in the new type apple juice was not observed during 100 days storage at room temperature. It was demonstrated that the enzymatic partial degradation of pectin was a useful method to produce clarified WSP containing apple juice containing WSP treated with ceramic membrane