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Flavored gelatin desserts have been made since the early 19th century, but required a great deal of work to clarify the gelatin and prepare it for use. The advent of Jell-o in the early 20th century made gelatin desserts quick and easy enough for any home cook to undertake. Jell-o makes approximately a 3 percent gelatin solution, enough to keep it firm in refrigeration or for a shorter time at room temperature. However, gelatin softens and melts at 95 degrees Fahrenheit, so you have to take care on hot days.

Keep Jell-o in the refrigerator until serving time. This is also advisable from a food-safety standpoint, since gelatin desserts are prone to spoilage, like other forms of protein.

Serve the Jell-o in frosted or refrigerated dishes or on a chilled platter to slow the warming process.

Cool the Jell-o to room temperature before placing it in the refrigerator. Slow cooling allows the gelatin molecules to form a stronger bond, which inhibits melting.

Add a teaspoon of unflavored gelatin to the recipe. Reinforcing the Jell-o with a small quantity of unflavored gelatin makes a stronger gel that resists melting.

Replace a portion of the water with alcohol when you make the Jell-o. Replacing 1 tablespoon of water in each cup with vodka or white rum helps the Jell-o form stronger molecular bonds, which help slow melting.

Store the Jell-o in a picnic cooler with several frozen gel packs if you don't have access to a refrigerator.

About the Author

Fred Decker

Fred Decker is a trained chef, former restaurateur and prolific freelance writer, with a special interest in all things related to food and nutrition. His work has appeared online on major sites including Livestrong.com, WorkingMother.com and the websites of the Houston Chronicle and San Francisco Chronicle; and offline in Canada's Foodservice & Hospitality magazine and his local daily newspaper. He was educated at Memorial University of Newfoundland and the Northern Alberta Institute of Technology.