Determination of total volatile basic nitrogen in aquatic products by nitrogen auto analyzer

Four species of aquatic products as Tilapia niloticus, Decapterus maruadsi, Litopenaeus vannamei and Crassostrea rivularis were pretreated by perchloric acid(HClO₄)solution to extract the total volatile basic nitrogen(TVBN), which was determined by nitrogen auto analyzer.The influence of different concentration of HClO₄ solution, extracting time and keeping time of the extract before distillation on determination was studied. The results showed that the recovery was between 98.42% and 101.18%, RSD was below 1.40%, by determinating the TVBN in aquatic products after the samples had been homogenized for 2 minutes at 0.6 mol · L^-1 HClO₄ solution.The result of this method had no significant difference compared with the distillation in GB/T 5009.44, and the operation was easy and rapid.