EXTRACTION OF CALCIUM, OXALATE CRYSTALS F ROM SESAME SEEDS

Sesame seeds were pulverized in a food blender and the free calcium an d oxalic acid were extracted from pulverized sesame seeds into boiling water. The total oxalic acid was extracted into 0.1 M hydrochloric ac id. Contents of calcium and oxalate were determined by AAS and ion chr omatography. On the other hand the sesame seeds pulverized in water po ured into a beaker. The calcium oxalate crystals which sank in the mix ture were carefully gathered by decanting the supernatant liquid. Seve nty milligrams and 800 mg of calcium were extracted into boiling water and 0.1 M hydrochloric acid, respectively from 100 g of sesame seeds. The total and free oxalic acids were found to be 1750 mg and 350 mg, respectively, per 100 g of sesame seeds. As the total calcium content in 100 g of sesame seeds was 800 mg, the nutrient calcium content was estimated to be 165 mg from the difference between the content of calc ium in calcium oxalate and the total calcium.