When chitooligosaccharide (COS) is added to fruit juice as a functional ingredient, citrate in the juice causes undesirable precipitation of a COS-pectin is complex. We assessed the interaction of COS, pectin, and citrate in fruit juice to provide a reference for the use of chitooligosaccharide in fruit juices. A high COS concentration and a small amount of citrate caused formation of a precipitate
at 10 mM citrate, the turbidity of the solution was highest, 59.96% (