Acetylated pectic polysaccharides of sugar beet

Acetylated pectin has been isolated from whole sugar beet tissue and from sugar beet pulp. A variety of extraction sequences and fractionation procedures were employed; all the extracts were of the pectin polysaccharide type containing 44-60% uronate, 12-22% neutral sugars, 4-6% methoxyl and 2-9% acetyl groups. The neutral sugars rhamnose, arabinose and galactose were present in all the extracts. and were covalently linked to the acidic polymer. Many of the extracts were surface active, and possessed foaming and emulsifying properties. Typically, foam volumes of 20-50% with t(1/2) of 120-180 min were obtained. The extracts were used to emulsify a model oil-in-water system containing 10%(v/v) groundnut oil. Oil droplet sizes of similar to 1 mu m were obtained, considerably less than those obtained with commercial pectins, and the emulsions were stable for at least 36 h at 4 degrees C. No correlations could be found between the foaming/emulsifying properties of the acetylated pectin fractions and their chemical structure.