AbstractThe recovery of bioactive compounds from agro‐industrial residues with green solvents in ultrasound‐assisted extraction (UAE) processes represents an interesting alternative from environmental and economical perspectives. Here we investigated optimal conditions to improve the extraction of anthocyanins from blackberry pomace. The experimental data were fitted to the second‐order polynomial model to obtain the regression coefficients, and three‐dimensional (3‐D) response surface plots were considered to represent the relationships between each variable on the response of total monomeric anthocyanin (TMA) content. The ultrasound‐assisted process at an ultrasound amplitude of 40% for 10 min and a concentration of 25 mg/L resulted in the maximum TMA concentration of 1.39 ± 0.02 mgCy3GlE/g. At these extraction conditions, the extract presented total polyphenol and flavonoid contents of 44.12 ± 0.17 mgGAE/g and 63.25 ± 0.53 mgQE/g, respectively. A total of 31 individual compounds, including anthocyanins, flavonols, and phenolic acids, were identified in the extract. Concentrations of cyanidin‐3‐glucoside and caffeic, gallic, and ellagic acids were 2.38 ± 0.09, 0.47 ± 0.01, 0.55 ± 0.01, and 0.48 ± 0.01 mg/g, respectively. Compared to the conventional extraction, the UAE represented an increase of 20.87% in total anthocyanins. Thus, the UAE at suitable conditions is suggested to recover bioactive compounds from blackberry pomace.Practical ApplicationsThe use of blackberry pomace to extract bioactive compounds is promising because it uses a by‐product from the fruit processing industry. This study presents an innovative proposal of optimal process conditions to recover anthocyanins from blackberry pomace under ultrasound irradiation. The use of green solvents, as water, in ultrasound‐assisted extraction (UAE) processes, represents an interesting alternative from environmental and economical perspectives, UAE process is a favorable, fast, efficient, and environmentally friendly method. The obtained blackberry pomace powder is an interesting ingredient to food and pharmaceutical industries, mainly due to the elevated concentration of added‐value compounds. Besides the high amount of anthocyanins content, which could be used as a dye and as antioxidant compounds in several types of food.
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