Influence of ultrasound and extraction conditions on the intensity of extraction of anthocyanin pigment from berry raw materials

Abstract

The effect of ultrasound and extraction conditions on the degree of anthocyanin pigment extraction from berry raw materials has been studied. It has been shown that the use of ultrasound for extraction allows increasing the anthocyanin pigment yield. The ultrasound-assisted water extraction at 25°C for 30 minutes increases the yield of pigment in aqueous solution by 22 %. The increase in the ultrasound-assisted extraction temperature to 65°C reduces the extraction time down to 15 minutes. It has been shown that the use of ultrasound reduces the extraction degree in 96 % ethanol and in the ethanol/water/hydrochloric acid system and increases the amount of anthocyanin pigment into the solution containing water as an extraction agent. In this case, the use of the ultrasound-assisted extraction reduces the anthocyanin pigment extraction time to 20 minutes with the use of the 96 % ethanol as an extraction agent, and to 15 minutes in an aqueous solution. The study of the ultrasound-assisted extraction effect, as well as the frequency and power of ultrasonic vibrations on the anthocyanin pigment extraction intensity has shown that the indirect ultrasound-assisted extraction (ultrasonic bath) with the ultrasound exposure frequency of 35 kHz and the power of 80 W allows allocating the anthocyanin pigment to the fullest extent possible within 30 minutes. With the direct ultrasound exposure (ultrasonic homogenizer) with the frequency of 20 kHz and the power of 75 W, the extraction time with an aqueous solution is reduced to 15 minutes, and with 96 % ethanol - to 20 minutes.