CHANGES IN HARDNESS AND CELL-WALL POLYSAC CHARIDES OF SMALL-SIZE UME-KOSHU-KOUME FRUIT DURING MATURATION AND ITS BRINING

The changes in cell wall polysaccharides constituents in relation to h ardness in small size ume fruit and Koumezuke (brined small size ume f ruit) were investigated. While small size ume fruit softened in textur e during maturation, the cell wall polysaccharides contents reduced to half from 2937 mg/100 g to 1460 mg/100 g. At the same time, the conte nt of the pectin fraction was increased 44.3 approximately 50.1%, and that of hemicellulose II and cellulose fractions were decreased, 17.4 approximately 11.9% and 25.9 approximately 21.9%, respectively. Koumez uke, brined in the solution calcium hydroxide was added and had a hard texture, had a constantly larger content of the cell wall polysacchar ides than the fruit brined only with NaCl. The decrease was observed i n pectin and hemicellulose I fractions components, on the other hand, hemicellulose II and cellulose fractions components were increased. Fu rthermore, ash and Ca bound to crude cell wall were remarkably larger in Koumezuke, and in the pectin fraction of Koumezuke, AGA content was small and neutral sugar content was large. From these results, the ma intenance of hardness of ume were only performed in case of brining wi th calcium hydroxide. This phenomena was supposed to be caused by the fortified cell wall with calcium hydroxide, and it was caused by the i ncreasing of hemicellulose II and cellulose fractions tightly bound to the cell wall which was formed through an obstruction of resolve of H SP and its combining with other cell wall constituents.