Studies on Pectolytic Enzymes of Molds

Part XIV. Properties of Pectin in Apple Juice

Abstract

Suspended particles in apple juice were successfully precipitated by ultracentrifugation. The particles were found to have a small amount of insoluble pectin as their component. Most of the pectin in apple juice was soluble type and remained in the supernatant. Both soluble and insoluble pectin contents of apple juice strongly affected the enzymatic clarifi-cation.
Purified endo-PGs of Coniothyrium diplodiella could decrease the viscosity of a solution of commercial citrus pectin (esterification degree 64%). However, they could not decrease the viscosity of native soluble pectin in apple juice, since carboxyl groups of the soluble pectin in apple juice were highly esterified (esterification degree ca. 90%).