The Difference Between Pectin And Gelatin
Pectin and gelatin have many uses in and out of the kitchen, but the two are most often used to thicken foods and liquids. They provide firmness, chew, and a gelling texture that helps set different foods to a desired consistency. They can also help extend the shelf-life of foods by preventing moisture loss. Both pectin and gelatin are colorless and flavorless and come in various forms, from powder to sheets to liquid.
While their culinary function is the same, the main difference between pectin and gelatin comes down to what they're made from. Pectin comes from fruit, and gelatin comes from animals. Pectin's most common form — HM — can be extracted from citrus peels. It's a water-soluble fiber found in plants, meaning it will dissolve in liquid. Gelatin is made from sources of collagen in animals, mainly pigs, and cows. It's pulled from connective tissues such as tendons and ligaments, as well as the bones and skin. The distinction between the two really comes down to a vegan-based thickener versus an animal-based one.
The best uses for each
Generally, the two are not interchangeable in recipes, though it really depends on what you're making. If you do swap one in for another, you will probably need to modify the technique you use. Pectin's most popular application is in jams, jellies, and marmalades. It firms and sets the fruit and creates that easy, spreadable texture. It is also used to provide the luscious mouthfeel in mousses and fruit fillings (think cherry pie).
Gelatin's most popular use is arguably Jell-O. It provides the jiggle that makes Jell-O, Jell-O. It is also often used to thicken gravies and sauces as it provides a smoothness to the finished product. Gelatin is what makes gummy candies chewy and marshmallows squishy. It is also used in dairy products and frozen foods because it serves as a stabilizer. Ice cream, yogurt, and whipped cream benefit from its abilities.
One difference to keep in mind if you're thinking about substituting one for the other is that pectin will dissolve in both hot and cold liquids, while gelatin only works in hot.