Diet rich in fruits and vegetables has been proven to exert a positive effect on preventing the development of a considerable number of chronic diseases such as cancer and cardiovascular diseases.This protective effect has been attributed to the high concentrations of functional compounds [1]. For the effective utilization of ingredients present in consumed foods, gut microflora plays an important role [2]. In this context, prebiotic oligosaccharides are
considered to be key compounds. Since the late 1990s and the birth of the prebiotic concept, many scientists have started studying the health properties of prebiotic compounds which resulted in a number of scientific publications describing them in relation to human
health [3,4]. The major prebiotic oligosaccharides in the market are fructo-oligosaccharides and galacto-oligosaccharides whose bioactive properties have been evaluated using a range of in vitro and in vivo methods [5–8]. The oligosaccharides are obtained by extraction from natural
sources or by chemical or enzymatic synthesis [9–12]. For extraction of low-molecular weight carbohydrates such as oligosaccharides from plant material, the optimal solvent is water [13].