Potentiometric flow injection determination of glycerol in distilled spirits.
A single-line flow injection system including a tubular periodate-selective electrode without inner reference solution is proposed for glycerol determination in distilled spirits, based on oxidation of this polyol by periodate. Interferences due to 5.0 mg L(-1) Cu, 5000 mg L(-1) sucrose, and 3000 mg L(-1) fructose plus glucose were investigated. The procedure is characterized by a linear response for 20-500 mg L(-1) glycerol (r > 0.9999, n = 7), a relative standard deviation of results of <0.03, and an analytical throughput of 30 determinations per hour. Accuracy was assessed by applying the procedure to distilled spirits of sugarcane and grape already analyzed by HPLC; in addition, recoveries within 96 and 120% were obtained.
Gervasio
Ana Paula G
AP
Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Box 96, Piracicaba SP 13400-970, Brazil.
Borges
Eduardo P
EP
Zagatto
Elias A G
EA
Reis
Boaventura F
BF
Lapa
Rui A S
RA
Lima
José L F C
JL
D000434:Alcoholic Beverages / Q000032:analysis*; D000431:Ethanol / Q000737:chemistry*; D017022:Flow Injection Analysis / Q000379:methods*; D005506:Food Contamination / Q000032:analysis; D005990:Glycerol / Q000032:analysis*; D011199:Potentiometry; D012680:Sensitivity and Specificity
D000431:Ethanol; D005990:Glycerol