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Recently I tossed out my ice cream maker. I've tried for years to make great ice cream; but it was never as good as what I could buy. So, I took a look at how ice cream is manufactured. I learned it's a very tricky business.
To the food engineer it's just air bubbles, oil globs and ice crystals suspended in water, but the key to engineering ice cream is getting all these bubbles, globs and crystals to be the right size. The oil comes from milk fat, which, of course, doesn't mix readily with the water. So the first step is a device that shatters the fat globules so they'll mix with the water, otherwise the cream will float to the top. Next, air is pumped in.
Ice cream can be up to fifty percent by weight air, although by law a half gallon must weight at least two pounds, two ounces. Adding in the right amount of air can make the difference between mediocre and excellent ice cream.
Too much air insulates the ice cream, making it melt slowly in our mouths and ruining its flavor. As it melts the chemicals containing the flavor are actually boiled on our tongues. The tropical orchard vanilla, for example, contains dozens of flavors. Each has a different boiling point that makes the vanilla play out in a certain time sequence on our taste buds. The more air then, the slower the melting and the less rich the flavor.
So, when you're in the supermarket checking out ice cream what should you look for? Find the highest density ice cream; that is, the heaviest half gallon. Most ice creams weigh close to the legal limit of two pounds, but premium brands can be nearly twice as heavy.
After you buy it I suggest you rush home. It is imperative to keep the ice cream at a constant temperature, otherwise it loses texture. If the ice crystals are bigger than one-thousandth of an inch, the touch receptors in the roofs of our mouths detect them. So, when you get that ice cream home, toss it in the freezer, and keep it closed. Opening the door makes the freezer heat up only slightly, but enough to melt the ice crystals. Then when the door is closed the water freezes, but this time freezing into larger crystals that make the ice cream crunchy.
One more ice cream tip for you: If you want excellent ice cream, go to New Zealand. They rank number one, per capita, in ice cream consumption. Each person eats about seven gallons a year. Their snow-fed rivers, clean air, sunshine and year-round grazing on rolling pastures lets their cows make milk that produces some of the best ice cream you'll ever taste.
Copyright 2003 William S. Hammack Enterprises