Abstract: Alum addition can improve quality of jellyfish products , but cause aluminum residue, so it is necessary to guarantee their safety by mornitoring relevant products. The alum content in the jellyfish was detected by titration method with ethylene diamine tetracetic acid (EDTA). Acid solutions were adopted in pretreatment instead of aqueous sdution ; and effects of acid variety, concentration of acid, and boiling time on determination results and filtration efficiency were analyzed. The results showed that, after being treated by 0.6 mol/L HClO4 and boiled for 6 min, the filtration speed of sample is accelerated, and the determination result is higher than that of standard method. identical with that by ICP-OES method. The average recovery rate of this method is 98.91%, the relative standard deviation is 1.69%, and the detection limit is 0.05%.By boiling treatment with HClO4, and the accuracy and precision are improved. This method can be used more suitably for the alum determination in jellyfish products.

Key words: jellyfish products, alum, titration, determination