INVESTIGADORES
GARCIA Maria Alejandra
artículos
Título:
Effect of controlled storage on thermal, mechanical and barrier properties of plasticized films from different starch sources.
Autor/es:
MALI, S.; GROSSMAN, M.V.; GARCIA, M. A.; MARTINO, M.N.; ZARITZKY, N.E.
Revista:
JOURNAL OF FOOD ENGINEERING
Referencias:
Año: 2006 vol. 75 p. 453 - 460
ISSN:
0260-8774
Resumen:
Thermal, mechanical and barrier properties of corn, cassava and yam starch films were determined and the behavior of these
three starches films under a controlled storage (64% RH and 20 C) was compared. Glass transition (Tg) in all unplasticized films
was higher than in plasticized, and during storage, Tg decreased, except for samples with 40 g glycerol/100 g starch. Crystallinity was
affected by plasticizer concentration and storage time; in unplasticized samples the increase in crystallinity was higher than in plasticized
ones during storage, thus, unplasticized stored samples become more brittle and less permeable during storage. Unplasticized
films showed water vapor permeability (WVP) values ranged from 6.75 to 8.33 · 1010 g m1 s1 Pa1. These values decrease when
glycerol content reached at 20 g/100 g starch because a more compact structure was formed and, then, at 40 g glycerol/100 g starch,
WVP increased because film matrixes became less dense.C) was compared. Glass transition (Tg) in all unplasticized films
was higher than in plasticized, and during storage, Tg decreased, except for samples with 40 g glycerol/100 g starch. Crystallinity was
affected by plasticizer concentration and storage time; in unplasticized samples the increase in crystallinity was higher than in plasticized
ones during storage, thus, unplasticized stored samples become more brittle and less permeable during storage. Unplasticized
films showed water vapor permeability (WVP) values ranged from 6.75 to 8.33 · 1010 g m1 s1 Pa1. These values decrease when
glycerol content reached at 20 g/100 g starch because a more compact structure was formed and, then, at 40 g glycerol/100 g starch,
WVP increased because film matrixes became less dense.Tg decreased, except for samples with 40 g glycerol/100 g starch. Crystallinity was
affected by plasticizer concentration and storage time; in unplasticized samples the increase in crystallinity was higher than in plasticized
ones during storage, thus, unplasticized stored samples become more brittle and less permeable during storage. Unplasticized
films showed water vapor permeability (WVP) values ranged from 6.75 to 8.33 · 1010 g m1 s1 Pa1. These values decrease when
glycerol content reached at 20 g/100 g starch because a more compact structure was formed and, then, at 40 g glycerol/100 g starch,
WVP increased because film matrixes became less dense.· 1010 g m1 s1 Pa1. These values decrease when
glycerol content reached at 20 g/100 g starch because a more compact structure was formed and, then, at 40 g glycerol/100 g starch,
WVP increased because film matrixes became less dense.