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 vegetables do not allow obtaining products identical to natural products for biological value. At the same time, there is a need to provide the population with minor components of food, including concentrated form. The aim of the study was to preserve the minor components in canned fruit raw materials for a long time. The study was carried out comparing the data of bioflavonoids and vitamin C in fresh oranges and dehydrated oranges (immediately after dehydration and storage for 12 months). The analysis was performed by reversed-phase HPLC on Dionex Ultimate 3,000 chromatograph (‘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 of components was performed by comparison of retention times of standard flavonoid samples. Dehydration was done by means of resonant IR drying, gradually lowering the temperature from intense (67–75 °C) to soft (32–35 °C) temperature regimes. Analysis of chromatograms of fresh and dehydrated oranges shows that they all have a similar profile, but differ significantly in the content of certain components. The presence of vitamin C 1,926.9 mg per 1 g of dehydrated oranges was noted, which is identical to the content of 10 g of fresh orange. The following flavonoids have been found: prunus and a component related to the polymer form of naringin, the content in 1 g of dehydrated oranges is approximately seven times more than that for 1 g of fresh orange. The loss of vitamin C by 8% during storage of dehydrated orange for 12 months was noted, the amount of flavonoids varies insignificantly by 2–3%.Studies have shown that the technology of dehydration with the help of resonance IR drying allows to keep the minor components in the native state for a long time.