PHYTOCHEMICAL CONTENT, PHYSICOCHEMICAL AND MICROSTRUCTURAL PROPERTIES OF APPLE POWDER AS AFFECTED BY DRYING METHOD
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.
Copyright (c) 2020 Latin American Applied Research - An international journal
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Once a paper is accepted for publication, the author is assumed to have transferred its copyright to the Publisher. The Publisher will not, however, put any limitation on the personal freedom of the author to use material from the paper in other publications. From September 2019 it is required that authors explicitly sign a copyright release form before their paper gets published. The Author Copyright Release form can be found here