Possibility and prospects of preservation of minor components in technology of fruit raw materials conservation

According to modern research, traditional methods of preserving fruits and vegetablesdo not allow obtaining products identical to natural products for biological value. At the sametime, there is a need to provide the population with minor components of food, includingconcentrated form. The aim of the study was to preserve the minor components in canned fruitraw materials for a long time. The study was carried out comparing the data of bioflavonoids andvitamin C in fresh oranges and dehydrated oranges (immediately after dehydration and storagefor 12 months). The analysis was performed by reversed-phase HPLC on Dionex Ultimate 3,000chromatograph (‘Thermo Scientific’, USA) using Luna 5U C18(2) 100A, 5 µm 4.6 mm ×150 mm column (‘Phenomenex’, USA), system number 125617-12. The identification ofcomponents was performed by comparison of retention times of standard flavonoid samples.Dehydration was done by means of resonant IR drying, gradually lowering the temperature fromintense (67–75 °C) to soft (32–35 °C) temperature regimes. Analysis of chromatograms of freshand dehydrated oranges shows that they all have a similar profile, but differ significantly in thecontent of certain components. The presence of vitamin C 1,926.9 mg per 1 g of dehydratedoranges was noted, which is identical to the content of 10 g of fresh orange. The followingflavonoids have been found: prunus and a component related to the polymer form of naringin, thecontent in 1 g of dehydrated oranges is approximately seven times more than that for 1 g of freshorange. The loss of vitamin C by 8% during storage of dehydrated orange for 12 months wasnoted, the amount of flavonoids varies insignificantly by 2–3%.Studies have shown that thetechnology of dehydration with the help of resonance IR drying allows to keep the minorcomponents in the native state for a long time.