Pectin

Normal Pectin

Gels in the presence of high acid and sugar Liquid or powdered Lemon and lime peel

Pectic Acid

Overripe plant material Forms insoluble calcium pectate - firming effect Seen in canned tomatoes

Low Methoxyl Pectin formation

pH 3.2-4.0 because only carboxylate groups can participate No sugar needed - dietetic products A small amount of sugar is left to act as a tenderizer/texturizer - not as brittle

Jelly Making

0.5-1.0% pectin Acid - contributes flavor, 3.2 pH Sugar - Preservative (65%) final cooking temperature = 104.5 degrees C Some sugar is hydrolyzed to invert sugar

Low Methoxyl Pectin

Doesn't need sugar but does need calcium ion pH range = 2.5-6.5

Protopectin

Immature plant material 100% esterfication 16% methoxylation

Pectin

Mature plant material

Pectinic acid

Mature plant material

Gel strength

Measured by ridgelimeter, penetrometer, Instron or texture analyzer

Where does pectin occur?

Middle lamella "Cements" cells together

Pectin grade

Number of pounds of sugar that one pound of pectin can carry in a jelly influenced by MW and DE