Green Ultrasound-Assisted Extraction of Antioxidant Phenolic Compounds Determined by High Performance Liquid Chromatography from Bilberry (Vaccinium Myrtillus L.) Juice By-products

In this paper, the effect of ultrasound assisted extraction (UAE) combined with stirring and conventional technique of maceration of wild bilberry juice by-products has been studied. Juice by-products were subjected to conventional maceration by stirring, and ultrasound probe using four different ultrasonic intensities (4.4, 9.4, 13.4 and 16.7 W cm − 2 ). The anthocyanins and flavonol profile of the obtained extracts were studied by HPLC-DAD. UAE resulted in a decrease of monomeric anthocyanins. However, the total phenolic compounds was higher when ultrasound was used and the extracts obtained with this “green” technology were more antioxidants than the extracts obtained by conventional maceration. Lab parameters and absorbances at 420 and 520 nm showed greater recovery of yellow and red compounds when the ultrasonic intensity was higher. Graphical Abstract