365: Chemistry for Life
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  • June 10
  • Category: Materials
DAY 161

Ice Cream

What makes ice cream taste so good? Studies on physical chemistry and flavor release have benefited this sweet treat.

I scream; you scream; we all scream for ice cream. The reason is simple: Ice cream is an excellent example of the whole tasting better than the sum of its parts.By weight, ice cream is composed primarily of water (from milk and cream) with sweeteners such as corn syrup or sugar, flavorings, emulsifiers, stabilizers, milk solids, and milk fat. Milk fat gives ice cream its distinctive richness and characteristic smooth texture. Federal law mandates that anything labeled ice cream must contain at least 10% milk fat by weight. Some premium brands have as much as 20% of this high-calorie component.

These ingredients account for only part of what you find in a carton of ice cream, however. That’s because by volume, 20 to 50% of ice cream is air whipped into the mix during the early stages of the freezing process.

“There are no real chemical reactions that take place when you make ice cream,” says H. Douglas Goff, an ice-cream expert and professor in the department of food science at the University of Guelph, in Ontario, “but that doesn’t mean there isn’t plenty of chemistry.”

From a physical chemistry perspective, Goff says, ice cream has a colloidal structure. Tiny air bubbles and ice crystals are dispersed among liquid water and a network of destabilized fat globules. The structure contributes to the taste. “When you bite into ice cream, how the flavor is released into the mouth probably is a function of structure,” says Richard W. Hartel, professor of food engineering at the University of Wisconsin, Madison.

Visit “What’s That Stuff” to read more about ice cream.

Excerpted with permission, Chemical & Engineering News
Copyright © 2004 American Chemical Society