Alteraciones reológicas debidas a la congelación de sistemas a base de espesantes, fase grasa y estabilizante

NAVARRO A.S.; MARTINO M.N.; ZARITZKY N.E.

REVISTA INFORMACION TECNOLOGICA DEL CHILE

Centro de Información Tecnológica

Lugar: La Serena; Año: 1996 vol. 7 p. 21 - 25

0716-8756

Freezing rate effect was analyzed, together with the addition of triglycerides to model suspensions of commercial corn starch (7 and 10%, w/w) with and without xanthan gum (0.3%, w/w). Transient curves of shear stress of samples thawed under controlled conditions were recorded with a concentric cylinders viscometer. The Bird-Leider model was used to obtain the viscoelasticity and structural breakdown parameters for the different systems, obtaining satisfactory fitting. The lipid phase modified the viscoelastic properties of the model systems. In all cases, the ultra-rapidly frozen systems maintained the textural characteristics of the unfrozen samples. The addition of only 0.3% of xanthan gum protected the suspensions from the negative effect attributed to low freezing rates.