xmlui.ArtifactBrowser.SimpleSearch.filter.source:Scientific papers of the University of Pardubice. Series A, Faculty of Chemical Technology. 16 (2010)
ISSN:1211-5541
Abstract:
Sorption isotherms of comfrey (Symphytum officinale L.) root samples with
different particle size were obtained at 25 °C. The shape of isotherm was similar
to those of high-sugar-content foods and the particle size did not affect adsorption
process in the aw range used in this study. Blahovec–Yanniotis model was
considered to give the best fit over the whole range of aw tested. Various
parameters describing the properties of sorbed water derived from GAB and
Blahovec–Yanniotis models have been discussed. DSC method was used to
measure the glass transition temperatures (Tg) of root samples in relation to water
activity. The safe moisture content was determined in 13.39 g/100g in dried basis
at 25 °C. Combining of the Tg line with sorption isotherm in one plot showed that
6 Červenka L. et al./Sci. Pap. Univ. Pardubice Ser. A 16 (2010) 5–18
the glass transition temperature concept overestimated the temperature stability
for both root samples.
