Removal of Stone Cells From Guava Nectar

Abstract

Several methods have been investigated for reducing the grittiness of guava nectar caused by the presence of stone cells. Of the several methods tried, which included nitration, centrifugation, cyclone separation, and particle-size reduction using a colloid mill and a stone mill, centrifugation and treatment in the stone mill proved to be the best. When the nectars are centrifuged in a solid-basket centrifugal, the grittiness was completely eliminated, since the stone cells responsible for this grittiness are separated during the process. Nectars of similar quality were prepared by size reduction of the stone-cell particles in a stone or mustard mill. A comparison of both methods showed that higher yields of nectar are obtained when the stone mill is used to disintegrate the stone cell, but some discoloration results when pink-colored fruit is treated thus. Treatment in the stone mill also results in a higher loss of vitamin C when compared to the loss that results when the nectars are centrifuged.