Physical characteristics of sunflower wax-pectin aqueous solutions

BAÜMLER, ERICA; KERR, REBEKAH; CARELLI, AMALIA; MARTINI, SILVANA

Cincinnati, Ohio

Congreso; 102st AOCS Annual Meeting & Expo; 2011

AOCS

The aim of this study is to investigate some physical properties of emulsion pectin solutions containing sunflower wax, which are used as a basis for producing edible films. These films have long been used as an alternative to synthetic packing to prevent moisture migration between food and their environment. Rheological and optical characteristics of pectin aqueous solutions containing sunflower waxes were considered. The presence of wax crystals in the pectin solutions was observed using a polarized light microscope. The size of these crystals decreased as pectin concentration increased. This may be due to the emulsion stabilizing properties of pectin. The use of different rheological models to describe the viscoelastic behavior of pectin emulsion solutions was examined. Samples exhibited a non-Newtonian liquid behavior, which was best described by means of Herschel-Buckley model. Apparent viscosities were determined using this model, which increased with pectin content in the emulsion. When sunflower waxes were added the apparent viscosity in the emulsions decreased. The characterization of these solutions are useful to optimize the production of pectin-wax-based emulsion coatings to prolong the shelf-life of food products.