Titre :
|
Osmodehydrofreezing of apples: Structural and textural effects
|
Auteurs :
|
N. Tregunno ;
H. Goff
|
Type de document :
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article/chapitre/communication
|
Année de publication :
|
1996
|
Format :
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p. 471-479
|
Langues:
|
= Anglais
|
Catégories :
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INDUSTRIE AGRO-ALIMENTAIRE
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Mots-clés:
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POMME
;
DESHYDRATATION
;
CONGELATION
;
TEXTURE
;
RHEOLOGIE
|
Résumé :
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Osmodehydrofreezing refers to the combined process of partial drying in a concentrated solution (osmotic dehydration) followed by freezing. The physical properties of osmodehydrofrozen apple slices were determined. Granny Smith apples slices were dehydrated to the point of a 50% weight reduction using concentrated sugar solutions (sucrose, sorbitol, or 42 DE corn syrup solids [CSS]) and were frozen at -35 degrees C. Rheological testing (force deformation and small scale oscillatory deformation) indicated that the presence of sugars increased firmness of thawed/rehydrated tissue compared with apples treated in the same manner without sugar, however, untreated frozen controls were firmer than osmodehydrofrozen samples after thawing/rehydration, indicating that conditions used during osmotic dehydration (50 degrees C for 40 min) were too severe. Cryo-scanning electron microscopy revealed a smoothness of the middle lamella of cryoprotected cells and cracking in that of untreated, frozen cells.
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Source :
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Food research international, vol.29, n°5-6
|