Gels, sugar acid-pectin

Gels known as low water activity gels or sugar-acid-pectin gels, formed from highly methoxylated (esterified) pectins that contain more than 50% carboxyl groups esterified with methanol... 

Pectin, the substance that makes jellies and jams so jelly-like, can help lower blood cholesterol levels by forcing the body to make more bile acids. Pectin is a type of fiber, and like most fiber, pectin cannot be digested by the human body. Instead, the fiber moves slowly through the small intestines. When pectin encounters sugar and acid, its molecules trap water within its long chains, turning into a gel-like mass. This gel traps and eventually eliminates bile acids from the gut. When this happens, the body must make more bile acids, reducing the amount of cholesterol in the blood. 

Pectin.—This general term has been retained to designate pectinic acids which will form the customary pectin-sugar-acid gels. 

Fig. 3 Gel-permeation chromatogram of acid-soluble sugar-beet pectin degraded with endopolygalacturonase after pec-tinesterase demethoxylation.

Fig. 6 Gels from acid-soluble sugar-beet pectin, obtained by crosslinking with hydrogen peroxide and peroxidase. The gels are 22 ml each and contain 0.9%, 1.8% and 2.7% pectin, from left to right. No sugar, acid or calcium salts were used.

Pectins are readily soluble in water to give viscous stable solutions. However, the importance of pectin to industry, in particular the food industry, is the abihty of its solutions to form gels with sugar (ca 65% soHds) and acid or calcium ion under suitable conditions (51). 

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