Imagine a delicious matrix of fat globules, sugar, ice crystals and air bubbles suspended in a liquid serum. This unique soft and sweet structure of frozen foam is loved for its silky texture and rich creamy flavor. The process of making ice cream is simple enough, though it certainly produces a complex substance in the end.
First, a mix is prepared by combining milk fat (generally provided by cream), non-fat milk solids (just like how it sounds??-powdered non-fat milk), sugar, flavors and emulsifiers. Emulsifiers are interesting molecules which bind ingredients that otherwise do not mix. In ice cream, emulsifiers are extremely important in blending the ingredients into a smooth, creamy texture.
Ice cream, by U.S. standards, must contain at least ten percent milk fat, though premium ice creams contain up to 16 percent (let's face it, more fat is tastier). Ice cream must also weigh at least 4.5 pounds per gallon.
Before the mix is frozen, it must be homogenized (a process that breaks up the fat globules into small equal parts), pasteurized to kill any harmful bacteria and aged at a cool temperature. Air is then simultaneously whipped into the mix as it is frozen. This decreases the weight-volume of the mix by a percentage referred to as the \overrun"" of the ice cream. Higher overrun equates to more air.
Once the ice cream is drawn from the freezer, it's still not quite time to dig in. The ice cream is fairly soft at this stage (think Dairy Queen's soft-serve ice-cream) and must be hardened at an extremely cold temperature, -30 degrees Celsius. After a couple days of hardening, the delicious emulsion is ready to be consumed.
For the last two years, Laura has worked as a research assistant for UW-Madison food science professor, Rich Hartel, the campus' unofficial candy man.
