Premium
Thiamin Stability in Solids as Affected by the Glass Transition
Author(s) -
Bell L.N.,
White K.L.
Publication year - 2000
Publication title -
journal of food science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.772
H-Index - 150
eISSN - 1750-3841
pISSN - 0022-1147
DOI - 10.1111/j.1365-2621.2000.tb16035.x
Subject(s) - glass transition , polyvinylpyrrolidone , thermodynamics , reaction rate constant , chemistry , degradation (telecommunications) , materials science , mineralogy , kinetics , polymer chemistry , organic chemistry , polymer , physics , telecommunications , quantum mechanics , computer science
The stability of thiamin was evaluated in solid polyvinylpyrrolidone model systems as a function of water activity (a w ) and the glass transition. In the glassy state, thiamin degradation rate constants correlated with the glass transition temperature (T g ), decreasing as T g increased. Above a w 0.4, rate constants correlated better with a w rather than T g . However, rate constants decreased in the rubbery state above a w 0.4, which could be attributed to glass transition‐induced structural collapse. Glass transition effects (mobility considerations, collapse) have a larger effect on thiamin stability than a w , which should be recognized during the development of fortified food products.