Resumo

GALLO, A.; MAZZOBRE, M. F.; BUERA, M. P.  e  HERRERA, M. L.. Low resolution 1H-Pulsed NMR for sugar cristallization studies. Lat. Am. appl. res. [online]. 2003, vol.33, n.2, pp.97-102. ISSN 0327-0793.

The stability of food and other labile biological systems containing sugars has been related to the amorphous characteristics of the matrices which they formed, being inversely related to the degree of crystallization. It is thus necessary to explore the applicability of simple, non-destructive and reliable methods to analyze sugar crystallization. Solid fat content is a well-stablished AOCS method to study solid content in lipid systems. However, there are no literature reports on the use of this method to analyze sugar crystallization. Crystallization kinetics of concentrated trehalose and trehalose/salts solutions was followed by proton pulse nuclear magnetic resonance (¹Hp -NMR). Three different concen-trations (X_T= 0.60, 0.63 and 0.66) of trehalose solutions were crystallized to 25, 20, 15, 10 and 5°C and the degree of crystallization was investigated by following the index of solids with time. Crystallization rate was determined by a combined effect of supercooling and molecular diffusion. By analyzing trehalose systems by ¹H p-NMR, it was possible to confirm the effect of divalent cations on retarding sugar crystallization.

Palavras-chave : NMR; Crystallization; Trehalose Solutions; Divalent Cations.

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