Abstract
Infrared spectrometry by the KBr-pellet method was applied to the analysis of functional groups in 8 types of fruit pectic substances prepared in our laboratary and in 4 commercial types of pectic substances.
At the same time, the quantities of free and ester-type carboxyl groups were determined by neutralizing titration, and calcium and magnesium contents were determined by atomic absorption spectrometry.
The results obtained from the infrared absorption spectra of these pectic substances agreed with those from titration and atomic absorption spectrnmetry, especially in the degree of esterification and the contents of inorganic ions.
