Identification and quantification of soluble sugars in green beans by HPLC

An HPLC method has been performed and validated for soluble sugar analysis in green bean samples (Phaseolus vulgaris cv. Perona), with good linearity, accuracy and precision. Monosaccharides (fructose and glucose), disaccharide (sucrose) and the polyalcohol (myo-inositol) were identified in green beans samples, as well as two unknown compounds, whose content was less than 16% of total soluble sugars. Enzymatic assays using !-glucosidases were performed in order to clarify the identity of one of the components of this fraction (identified as myo-inositol). In all the batches of green beans analysed, fructose was the major sugar (0.88-1.44%), while sucrose (0.10-0.39%) and myo-inositol (0.08-0.66%) presented higher variability on the analysed samples.