Open AccessPHYTOCHEMICAL CONTENT, PHYSICOCHEMICAL AND MICROSTRUCTURAL PROPERTIES OF APPLE POWDER AS AFFECTED BY DRYING METHOD
Author(s) -
Seyed‑Ahmad Shahidi,
Shiva Roshani,
Azade GhorbaniHasanSaraei,
Shahram Naghizadeh Raeisi
Publication year - 2020
Publication title -
latin american applied research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.123
H-Index - 23
eISSN - 1851-8796
pISSN - 0327-0793
DOI - 10.52292/j.laar.2021.205
Subject(s) - food science , porosity , phytochemical , materials science , bulk density , chemistry , composite material , biochemistry , biology , ecology , soil water
Apple in forms of slice and juice dried through methods of freeze drying (FZD), microwave drying (MWD), oven drying (OVN), spray drying (SPD) and foam mat drying (FMD) and the resulted powders were characterized in terms of water activity, vitamin C (Vc), phenolic compounds (TP), anthocyanin (TA), density, porosity, color, glass transition temperature and microstructure. The nutritional quality of apple powders expressed by the amount of Vc, TP and TA was found to be in the highest level in samples obtained after FZD followed by SPD. The minimum shift of color indexes from fresh apple observed for FZD followed by MWD. The highest and lowest bulk and true density were noted after OVD and FMD, and FZD and SPD, respectively. DSC analysis showed the powders obtained from apple slice through FZD, MWD and OVD have significantly lower Tg than those of produced from apple juice, by SPD and FMD. Scanning electron micrograph confirmed the porous structure of FMD and FZD and the dense structure of OVD.