Physicochemical properties and antioxidant activity of spray-dry broccoli (Brassica oleracea var Italica) stalk and floret juice powders Article uri icon


  • This research presents the microencapsulation and conservation of antioxidants of broccoli juice processed by spray drying, and proposes the use of a by-product as a technological application. Broccoli juice (BJ) extracted from two sources, stalks and florets, was spray-dried employing mal-todextrin (MX) as a carrier agent at concentrations of 5, 7.5, and 10%25, and inlet temperatures of 150 and 220◦C. The total phenolic content (TPC), and antioxidant activity (AA) of the BJ-MX powders were determined together with the physicochemical characteristics, including particle morphology, microstructure, and thermal properties. Based on the TPC and AA, the optimal processing conditions found were 5%25 of MX and a drying temperature of 220◦C. However, the florets showed higher TPC, while stalks presented higher AA under those processing conditions. The particles exhibited micrometric sizes and a mixture of spherical-shape particles and pseudo-spherical particles. The diffractograms indicated an amorphous microstructure in all samples. The glass transition temperature (Tg) was determined in the range of 50◦C for the samples dried at 150◦C and 55◦C for those dried at 220◦C. This suggested that powders might be stored at temperatures below the Tg without presenting any loss of antioxidants. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

publication date

  • 2021-01-01