To most of us, ice cream is merely delicious. But to a food engineering professor like the College’s Rich Hartel, who has studied the creamy treat for fifteen years, it’s a phenomenon of physics.
“Half of ice cream is air in the form of air cells,” Hartel says in an online report by ScienceCentral reporter Karen Lurie. “About two thirds of it is in the form of ice crystals. So it’s a foam, it’s a dispersion, [and] it’s an emulsion — about twelve percent of ice cream is in the form of fat that’s spread out in small globules. It’s a very complex multi-phase system.”
A multi-phase system that needs to be creamy. “There are a lot of factors that affect creaminess,” Hartel explains. “The fat content is one, the ice crystals is another. If we have very large ice crystals, then it’s a coarse ice cream, not a smooth ice cream, and not a satisfactory eating experience. The smaller the crystals are, for the most part, the creamier the taste, the smoother the taste.”
Hartel offers his insights on what makes ice cream cream on an online video report from ScienceCentral news.