SMMART Science: Pectin

We received a lovely bunch of sweet plums this fall!  After eating and eating and eating these lovely purple little plums, we could eat no more...so we made a few batches of plum jam!

Instead of dropping the plums in boiling water to remove the skins, we just pitted them and blended the whole plums.  The girls enjoyed measuring and pouring in the pectin and sugar.  After observing the puree and then seeing it set up into jam, even I was marveling at the miracle of pectin.

"In cooking, pectin is used as a thickening agent, and could be considered one of the most natural types around. The first pectin available for purchase was derived from apples, which have a high amount of it. There are other fruits that naturally contain this gelling agent, including many plums and pears. The properties of pectin were discovered and identified by the French chemist and pharmacist, Henri Braconnot, and his discovery soon led to many manufacturers making deals with makers of apple juice to obtain the remains of pressed apples (pomace) that were then produced in a liquid form.

Pectin is a complex carbohydrate, which is found both in the cell walls of plants, and between the cell walls, helping to regulate the flow of water in between cells and keeping them rigid. You’ll note some plants begin to lose part of this complex carbohydrate as they age. Apples left out too long get soft and mushy as pectin diminishes. When apples are just ripe, they have a firm and crisp texture, mainly due to the presence of pectin." http://www.wisegeek.org/what-is-pectin.htm

"Pectin is commonly used as the active ingredient in cough drops because it coats the upper trachea and prevents the spasms which precede coughing. Under acidic conditions, pectin forms a gel. This effect is used for making jams and jellies." (http://www.all-science-fair-projects.com/science_fair_projects_encyclopedia/Pectin)