Page 142 - Analytical method for food addtives

E220–8: Sulphites 89

Reference 10,11 17
21 22

cm –1 for a time of 1.5 mins Detection Electrochemical (amperometric) v at +0.6 Fluorescence g 40 % aqueous nm ex 400 tetrabutylammonium nm em 470 g acetic acid in 700 mL
gas infrared cell. The flow injection (FI) recordings were
registered and the analytical variable was the area of the
The SO 2 evolved was swept by a stream of nitrogen to a

1300 cm –1 , at a resolution of 16 co-added spectra obtained, in wave number range 1429 and from the first SO 2 spectrum. External calibration with Na 2 S 2 O 5 solutions in 10 % ethanol, treated in the same way, was employed Total SO 2 was measured by EC1108/82 and EC2676/90 distillation methods, the modified Monier–Williams

To 1 mL sample, previously treated M KOH at 30 ºC, with 0.5 mL 1 M H 2 SO 4 was added 0.5 mL 3.4 Attention focused on total SO 2 legal limit of 10 mg/L fixed in Europe for grape juice Column Sample preparation/extraction Diluted portions of liquid samples or diluted filtrates of solid samples Blended with buffered formaldehyde solu

Musts and wines Grape juice Matrix Foods and beverages Foods columns

Comparison of 5 methods including distillation, iodimetric and enzyme-based chromatographic

FTIR (b) Method Ion exclusion IEC–EC HPLC