Physicochemical characterisation of the hydrocolloid from Brea

BERTUZZI, MARÍA A.; SLAVUTSKY, ANIBAL M.; ARMADA, MARGARITA

INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2012 vol. 47 p. 776 - 782

0950-5423

The Brea Gum (BG) is a hydrocolloid obtained as phloematic exudate from Cercidium praecox. The exudate was purified by solution and subsequent drying.. BG showed high solubility in water 28.3% at 25ºC that increased as temperature was raised. Viscosity of BG solutions increased with BG concentration increase and temperature decrease. Addition of acid or alkali produced changes in solution viscosity as the electrostatic charges on the macromolecule were altered. Solution density at 25°C increased linearly with the hydrocolloid concentration up to saturation. BG lowered the surface tension of water from 72 to 52 dynes/cm when BG concentration was lower than 3%. No further decrease in surface tension was detected at higher concentrations,. Diameter of emulsified oil droplets in water decreased exponentially with increasing gum concentration used as emulsifier. Stability and durability of foams improved with hydrocolloid concentration. BG has adequate functional characteristics for use as emulsifier, thickener and stabilizer.