Premium
‘Collapse’, a structural transition in freeze dried carbohydrates
Author(s) -
TO EDDIE C.,
FLINK JAMES M.
Publication year - 1978
Publication title -
international journal of food science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.831
H-Index - 96
eISSN - 1365-2621
pISSN - 0950-5423
DOI - 10.1111/j.1365-2621.1978.tb00838.x
Subject(s) - recrystallization (geology) , sucrose , freeze drying , acetone , maltodextrin , amorphous solid , chemistry , glass transition , chromatography , chemical engineering , materials science , crystallography , spray drying , food science , organic chemistry , geology , polymer , paleontology , engineering
Summary A quantitative correlation between loss of entrapped volatiles and ‘collapse’ was established using methods which permitted the degree of ‘collapse’ to be measured. The chronological relationship between ‘collapse’, recrystallization and volatile loss was studied in sucrose–acetone systems using DTA. The structure of sucrose–acetone systems after freeze drying (i.e. a crystalline or amorphous matrix) depended on the composition of the starting solution rather than on conditions during freeze drying. Oxidation behaviour of freeze dried linoleic acid–maltodextrin–glucose emulsions with different ‘collapse’ temperatures was explained based on recrystallization of the matrices. In the absence of deliberate rehumidification, recrystallization of some freeze dried carbohydrates was found to occur by heating past ‘collapse’ and holding at these elevated temperatures. There were indications that loss of volatiles and oxidation of entrapped fat is more rapid after the structure turned crystalline than when it was merely in the ‘collapsed’ condition.