A Glucotest for the Quality Control of Food Raw Materials and Products

Ready-to-use indicatory forms shaped as tablets, e.g., glucotests, are proposed for the rapid semi-quantitative determination of glucose in foodstuffs. Their function is based on the classical Fehling's reaction with the selection of reagents aimed to eliminate the influence of proteins, reduce sample pretreatment to a minimum, and perform the test within 10 min. The glucotests are economical, simple to manufacture, and have no limits for shelf life and storage conditions. If necessary, the glucotests can be applied for the quantitative determination of glucose as well. To do this, a photometric procedure is proposed based on the quantification of unreacted copper acetate in the composition of the glucotest by its intrinsic absorbance. To analyze colorful products, sample pretreatment using an anion-exchange resin in the acetate form is recommended.