BIAMPEROMETRIC TITRATION AND FLOW-INJECTION DETERMINATION OF CYCLAMATE IN LOW-CALORIE PRODUCTS

Titration and flow injection (FI) methods with biamperometric detection at 0.7 V are proposed for determining cyclamate and are tested for various diet products. The titrant-reagent system was sodium nitrite in 1.0 mol 1(-1) phosphoric acid and there was no interference from glucose, fructose, sucrose, lactose, sorbitol, saccharin, benzoic acid, salicylic acid, fumaric acid, Sunset Yellow and Bordeaux-S. For the biamperometric titration method, the detection limit was 1.3 x 10(-3) mol 1(-1) and the relative standard deviation (s(r)) was 1.0% for a solution containing 5.0 x 10(-3) mol 1(-1) cyclamate (n = 9). The recovery of the sweetener from four low-calorie products ranged from 97.6 to 102.5% of the labelled amount, For the FI method there was a direct relation between cyclamate concentration and current decrease over 5.0 x 10(-3) to 4.0 x 10(-2) mol 1(-1) cyclamate with a detection limit of 2.5, x 10(-3) mol 1(-1) and an s(r) of 1.7% for a solution containing 2.5 x 10(-2) mol 1(-1) cyclamate (n = 10). Ninety results can be obtained per hour, and these, for various low-calorie products, are in good agreement with those obtained by a spectrophotometric FI method (r = 0.9993) and/or the labelled amount (r = 0.9937).