The levels of invert sugar (glucose/fructose mixture resulting from inversion) were determined in different brands of orange, grapefruit, lemon, apricot and raspberry products. Samples of fresh juice, soft drink, syrup, nectar and compote were representative of the Romanian market. The invert sugar was quantified by Ofner’s method (a titrimetric method) and the refractive and Brix indices were measured for the quantification of sucrose in studied samples. International Commission for Uniform Methods of Sugar Analysis accepts reading of sugar content based on the refractive properties of sucrose despite the fact that the sugar in analyzed juice sample is fructose, not sucrose. This usually does not result in significant error. There were significant differences among orange, grapefruit, lemon, apricot and raspberry products brands, in the levels of sugars.
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