Tincture Preparation from Northern High Bush Blueberries and a Study of Their Influence on the Cosmetic Emulsion Properties

Abstract

We have studied the effect from maceration duration (1-7 days) and extraction solvent concentration (ethanol - 30, 40, 70 %) on the content of flavonoids and anthocyanins in Bluecrop blueberry tincture. The ratio between raw material and extraction solvent for the berry tincture preparation was 1: 10. It was determined that extraction must be done by 70 % ethanol for 5 days in order to ensure a larger volume of analyzed bioactive components in the tincture. Under these extraction conditions the content of flavonoids and anthocyanins in the extract was about 2810.0 +/- 121.3 and 313.8 +/- 8.3 mg/100 g of raw material consequently. We have studied the effect from northern blueberry tincture consumption on the properties of cosmetic emulsion containing vegetable oil. Emulsion samples were received according "hot/hot" procedure. The tincture was introduced into the emulsion after its cooling to 4045 degrees C and additionally dispersed. The samples were exposed to the accelerated aging (thermostat incubation at a temperature of 40-42 degrees C) in order to study emulsion stability to oxidation on addition of the northern blueberry tincture. Stability was evaluated on the basis of change of emulsion peroxide and acid numbers. It was shown that the tincture of 1-5 % wt does not effect on colloidal stability of emulsion which retains homogeneity after centrifuging for 5 min at 6000 min(-1). With introduction of berry tincture the emulsion gets a pinky colour and slight berry aroma, which become stronger with increase of the added component amount. The northern blueberry tincture of 3-5 % wt increases resistance of cosmetic emulsion to oxidation due to presence of natural antioxidants.