Polymorphism and growth behavior of low-trans fat blends formulated with and without emulsifiers

MARINA CERDEIRA, SILVANA MARTINI, ROBERTO J CANDAL, MARIA L HERRERA

JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY (JAOCS)

AOCS Press

Lugar: Champaign, USA; Año: 2006 vol. 83 p. 489 - 496

0003-021X

Polymorphism and growth behavior of blends of a high melting fraction of milk fat (HMF) and sunflower oil (SFO) formulated with and without addition of the sucrose esters (SE) P-170, P-1670, and S-170 were studied by pulse nuclear magnetic resonance (1H p-NMR), X-Ray diffraction (XRD), and polarized light microscopy (PLM). The effect of SE on maximum solid content (Smax) or crystallization rate was observed only at low supercoolings (values of DT below 15°C). Avrami kn decreased while n values increased indicating that SE inhibited growth and impeded nucleation. Addition of SFO modified the polymorphic behavior of milk fat most likely due to increase of the C54 fraction (mostly 18:1 cis) in crystals composition. The sucrose esters (SE) P-170 and S-170 modified the polymorphic behavior of HMF when it crystallized in the a-form or of its blends with SFO at all crystallization temperatures (Tc) selected up to 40% SFO addition. Crystallization in the b’- form was favored and the appearance of the b- form was delayed. P-1670 had no effect on polymorphism. When HMF and the blends were crystallized in dynamic conditions, addition of P-170 and S-170 markedly decreased crystal size. P-1670 however, showed no effect on microstructure.