title: Microwave-assisted drying of blueberry (Vaccinium corymbosum L.) fruits: Drying kinetics, polyphenols, anthocyanins, antioxidant capacity, colour and texture.
abstract: The aim of the study was to evaluate the effect of hot air convective drying (HACD), microwave vacuum drying (MWVD) and their combination (HACD+MWVD) on the drying kinetics, colour, total polyphenols, anthocyanins antioxidant capacity and texture of frozen/thawed blueberries. Drying resulted in reduction of total polyphenols content and antioxidant capacity (69 and 77%, respectively). The highest content of total polyphenols was noted after HACD at 90°C. Lower air temperature and prolonged exposure to oxygen resulted in greater degradation of polyphenols and antioxidant capacity. Drying processes caused a significant decrease (from 70 to 95%) in the content of anthocyanins. The highest content of anthocyanins and the strongest antioxidant capacity was found in blueberries dried using HACD at 90°C+MWVD. Among drying methods, HACD at 90°C+MWVD satisfied significant requirements for dried fruits i.e. short drying time and improved product quality.
authors.affiliation: Department of Systems Engineering, University of Warmia and Mazury in Olsztyn, Heweliusza 14, 10-718 Olsztyn, Poland. Electronic address: m.zielinska@uwm.edu.pl.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Zielinska
authors.affiliation: Institute of Animal Reproduction and Food Research of the Polish Academy of Sciences, Division of Food Science, Tuwima 10, 10-748 Olsztyn, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Michalska
mesh_terms: D000872:Anthocyanins / Q000737:chemistry*; D000975:Antioxidants / Q000737:chemistry*; D029798:Blueberry Plants / Q000737:chemistry*; D003116:Color; D003890:Desiccation / Q000379:methods*; D005638:Fruit / Q000737:chemistry*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008872:Microwaves; D059808:Polyphenols / Q000032:analysis* / Q000737:chemistry; D013696:Temperature; D014618:Vacuum
chemical_list: D000872:Anthocyanins; D000975:Antioxidants; D059808:Polyphenols
keywords: Antioxidant capacity; Colour; Microwave-assisted drying kinetics; Texture; Total monomeric anthocyanins; Total polyphenols; Vaccinium corymbosum