Uso De Um Detector Potenciométrico De Sensibilidade Aumentada Para a Determinação De Cloretos Em Leite E Produtos Lácteos Por Fia Potentiometric Flow Titration With Increased Sensitive Detector for Determination of Chlorides in Milk and Dairy Products Uso De Un Detector Potenciométrico De Sensibilidad Aumentada Por Fia Para La Determinación De Cloruros en Leche Y Productos Lacteos

Abstract

This paper describes the development of a flow injection analysis (FIA) system for the determination of chlorides in dairy products by potentiometric flow titration with increased sensitive detector. The potentiometric detection system used consisted of a silver ion-selective detector electrode based on a homogeneous crystalline double membrane and its potential difference was measured against a common reference electrode by an external electronic device. Milk samples were straight injected into the automatic system whereas cheese, butter and yoghurt samples were prepared according to reference methods and the solution produced was inserted without further treatment. The results obtained for chloride determinations using FIA titration are in agreement with those provided by the reference methods (R.D. < 4%). The sampling rate accomplished with the automatic system varied from 130 to 250 samples per hour, depending on the samples chloride concentration.