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Titre :
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Control of impregnation phenomena during quick immersion chilling and freezing
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Auteurs :
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T. Lucas ;
A. Raoult-Wack ;
A. Sereno ;
CIRAD MONTPELLIER ;
19th international congress of refrigeration, The Hague NLD, 20-25 august 1995, vol II (1995; NLD) ;
UNIVERSIDADE PORTO POR
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Type de document :
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article/chapitre/communication
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Année de publication :
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1995
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Format :
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p.242-248
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Note générale :
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Sigle : CIRAD
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Langues:
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= Anglais
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Mots-clés:
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REFRIGERATION PAR IMMERSION
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CONGELATION PAR IMMERSION
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PRODUIT ALIMENTAIRE
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TRANSFERT DE MASSE
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TRANSFERT DE CHALEUR
;
CHLORURE DE SODIUM
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Résumé :
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Immersion chilling and freezing consists in dipping a food product to be chilled and freezed into a concentrated aqueous solution (salt, sugar, ethanol...) at low temperature. This process is still empirical and its full economical development has been hindered by undesirable uptakes of solute in the product. A preliminary study of heat and mass transfer was carried out on gel cylinders dipped into NaCl solution. The effects of the phase contacting modes and the concentration/temperature in the solution on water loss, salt gain and freezing phenomena was observed. This work revealed that mass transfer could be controlled by modifying process variables and that in freezing conditions, the quick formation of a continuous ice barrier would limit mass transfer (water and solute). The main mechanisms take place in the surface layer of the product, whether the concentrated salt uptake or the formation of the ice barrier.
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