Preparation of calcium powder from cooking skipjack tuna bone and its characteristics

Abstract

As a part of investigation for utilizing of canned tuna processing by-products as a food resource, we examined the processing conditions and characteristics (extraction methods and ashing condition) of a calcium powder from skipjack tuna bone. Among ashing, autoclaving, and shaking methods for extraction of calcium powder from skipjack tuna bone, ashing method was superior to other methods on the aspect of fish odor, white index, and calcium recovery of calcium powder. Based on the results of white index and soluble calcium ratio, the optimal ashing temperature and time for preparation of a calcium powder from skipjack tuna bone was at . Cohesive ratio of calcium powder by shaking at pH 7.0 was increased up to 16 hrs, but after that almost unchanged. Cohesive ratio of calcium powder by shaking for 24 hrs was increased at neutral and alkaline conditions (pH 6-8 and pH 9-11), but almost unchanged at acidic conditions (pH 2-5). For the effective utilization of the calcium powder from skipjack tuna bone, a suitable treatment is needed for improvement of calcium solubility at neutral condition.