Development of identification criteria for fruit vodkas (Part 1. Sample preparation ways)

The development of reliable identification criteria for various types of foods, including fruit vodkas, is one of the top-priority directions of scientific research in the field of quality control. The review examines different approaches to solution to a problem of searching identification criteria for fruit vodkas that will allow differentiating products by a type of fruit raw materials, their grade and region of origin. To this end, instrumental methods of analysis were used, including spectral, high performance liquid chromatography (HPLC) and gas chromatography coupled to mass spectrometry (GC–MS) as the main method. When detecting minor aroma-forming substances using the latter method, it is necessary, first of all, to carry out the special sample preparation that includes extraction and concentration of target substances. The present review examines three main types of sample preparation (liquid extraction, solid-phase extraction, supercritical fluid extraction) and modifications of these methods. Their comparative analysis was carried out with respect to labor intensity, extraction effectiveness, volatile aroma-forming compounds significantly different by polarity, reproducibility and sustainability. It has been shown that a type of sample preparation affects reproducibility and sensitivity of an instrumental analytic method, which is especially important for identification of some minor compounds, which concentration can be regarded as indicators for identification of fruit raw materials. It has been concluded that among the examined methods of sample preparation, the most promising for the development of identification criteria for fruit vodkas is headspace solid-phase microextraction (HS-SPME) as this method is highly effective in terms of extraction of target components including minor.