Identification and Quantitation of the Main Constituents of Sour Cherries: Simultaneously, as their Trimethylsilyl Derivatives, by Gas Chromatography-Mass Spectrometry

A GC-MS method - developed for the simultaneous quantitation of mono-, di- and trisaccharides, sugar alcohols and acids, as their trimethylsilyl (oxime) ether/ester derivatives prepared in the presence of the fruit matrix has been extended. The reproducible determination of derivatized sour cherry constituents was performed both on the basis of total ion current (TIC) and selective ion values; ensuring their identification and quantitation over a wide concentration range (∼1 × 10−2 to ≥ 41%, calculated on dry matter basis of the samples). The GC-MS procedure was utilized to prove the advantage of the direct derivatization process, in the presence of the fruit matrix, and to determine the changes in the sugar/sugar alcohol/carboxylic acid/flavonoid hydrolysis products of three sour cherry cultivars, as a function of their harvesting dates and storage conditions. Reproducibility of quantitations in the case of the main constituents, calculated on the basis of their TIC values provided an average reproducibility of 2.3 and 3.6 RSD%, for components present in concentrations of ≥1% and ≤1%, respectively.