0000000000754818
AUTHOR
Tian Jiang
From ‘green’ technologies to ‘red’ antioxidant compounds extraction of purple corn: a combined ultrasound-ultrafiltration-purification approach
A pilot scale process consisting of ultrasound-assisted extraction, ammonium sulfate precipitation, cross-flow ultrafiltration and AB-8 macroporous resins purification aiming to recover anthocyanins and zein from purple corn (PC) was optimized and scaled-up. The effects of five independent variables (ethanol concentration, liquid to solid ratio, ultrasound temperature, time and power) were discussed and the most influential factors were optimized.; Results: The highest total anthocyanin (0.45 ± 0.01 g kg-1 ) and zein (17.14 ± 1.73 g kg-1 ) contents from purple corn were obtained using an ultrasound power of 105 W, an extraction time of 90 min, an ethanol concentration of 74% and a liquid to…
Ultrasound-Assisted Extraction, Centrifugation and Ultrafiltration: Multistage Process for Polyphenol Recovery from Purple Sweet Potatoes
This work provides an evaluation of an ultrasound-assisted, combined extraction, centrifugation and ultrafiltration process for the optimal recovery of polyphenols. A purple sweet potato (PSP) extract has been obtained using ultrasonic circulating extraction equipment at a power of 840 W, a frequency of 59 kHz and using water as solvent. Extract ultrafiltration, using polyethersulfone (PES), was carried out for the recovery of polyphenol, protein and anthocyanin. Pre-treatment, via the centrifugation of purple sweet potato extract at 2500 rpm over 6 min, led to better polyphenol recovery, with satisfactory protein removal (reused for future purposes), than PSP extract filtration without cen…