What makes ice cream melt? If you answered “the hot summer air,” you are only partly correct.
Other factors like fat content and additives dictate the speed at which the ice cream will liquefy. And researchers at Dundee and Edinburgh Universities in Scotland have discovered a new protein that could slow the melting, letting you enjoy your entire cone without any of it dripping onto your fingers.
A homemade or artisanal ice cream contains fat and water (as cream or milk), sugar, and maybe some eggs. And while the water content affects the rate of melting (more water means slower melting, if you don’t keep it in the freezer, it’s going to soften up and melt pretty fast.
The Dundee and Edinburgh team, led by researcher Cait MacPhee, have discovered a naturally-occurring protein called BslA, which binds to the fat and air in the ice cream to stop it liquefying as the temperature rises. It’s similar to how an emulsifier like egg yolk keeps fat and water in a stable emulsion in regular ice cream, or mustard helps keep your French dressing from splitting into a messy sludge.
BslA is a water-repelling protein grown from bacteria and can be used to make biofilms. When added to your ice cream mix, BslA binds with the air and fat in the mix, but repels the water. This keeps it in a nice creamy gel even at higher temperatures. It also stops ice-crystals from forming, which means that you can keep taking it out of the freezer for a quick spoonful without it getting all icy. The retardation of ice crystal growth makes manufacture easier too. “We’re excited by the potential this new ingredient has for improving ice cream, both for consumers and for manufacturers,” says MacPhee.
Because this magic ice cream is stable at relatively high (for ice cream) temperatures, it doesn’t need a deep-freeze–you only need to keep it cold enough to ensure it’s safe and pleasant to eat. No more waiting for dessert to soften up before you can eat it.