REFRACTOMETRY METHOD IN STUDY OF FATTY OILS AND THEIR BLENDS AS EXTRACTANTS OF PLANT RAW MATERIALS

Abstract

The paper presents the study of refraction index, iodine number and relative percentage of fat content of a series of industrial vegetable oils, their two- and three-component blends and oil extracts of dry crushed medicinal plant raw materials (St. John's wort, celandine and dandelion root) by refractometry method. Oil extracts of plant raw materials were obtained in a water bath at 90° C within an hour followed by exposure for five months at room temperature. Before measurement, extracts were cleared by centrifuge process. We showed the influence of nature, ratio and mixing order of components on the optical properties of the simulated two- and three-component oil compositions due to structural and chemical transformations of triglyceride associates of individual oils in blends. The marked selectivity of individual oils-extractors was represented, regardless of their belonging to a certain classification group, as well as the increase in the extractive capacity of blended compositions in respect of plant raw materials of different nature and its anatomical parts. It was shown that the selectivity of the extractants is influenced by the presence of parallel running contra-directional and also the selective adsorption processes of lipophilic components of the oils and their blends by plant raw materials in the studied heterogeneous systems.

Keywords

• vegetable oils
• oil blends
• oil extracts
• plant raw materials
• refractometry method