Regardless of your frozen preference, the process and science of making your own list of favorites is quite similar.  The target is a great taste and a perfect texture.  The ice cream should be sweet and flavorful; the texture should be smooth, semi-firm, and melt in the mouth without any waxy feel.  To accomplish this, the ingredients must be fresh, first quality, and in the right proportions.  The freezing process must produce a consistent, fine, icy crystal.

The Ingredient Mix - In its simplest form, ice cream is made from milk, sugar, cream, and flavorings.  A good ice cream needs some of each of these ingredients to freeze well and taste good.  The milk provides proteins essential for creating a structure that captures air bubbles and separates fat globules.  The sugar provides sweetness and a lower freezing temperature that keeps the ice cream from freezing rock hard.  The cream supplies the characteristic richness.  Butterfat, the type of fat found in cream and all dairy products, is a complex fat whose components melt at different temperatures producing a cascading effect as it passes through the mouth.  If the ice cream contains eggs, it is known as a French custard-style; without eggs it is termed Philadelphia-style.  With the sweet cream mixtures as a canvas, imaginative flavorings provide the unique tastes we've come to love. 

The Freezing Process - After the ingredients are mixed, the freezing process will determine the final result.  A cold mixture that has been refrigerated for at least two hours will facilitate freezing.  Regardless of the machine used for freezing the ice cream, cold temperatures are transferred indirectly to the mixture through some type of metal container.  (See types of ice cream machines below).  Continuous movement of the mixture while in contact with the freezing metal is pivotal to the process.  Known as churning, or spinning, a paddle or dasher stands in the center of the mixture and connects to a crank.  Turning the crank moves the dasher's blade along the insides of the metal container forcing newly formed ice crystals back into the mixture.  The ice cream's temperature is lowered evenly and efficiently while allowing only the smallest of ice crystals to form.  Within 20-30 minutes, the mixture grows more difficult to crank as it freezes and solidifies.  The ice cream may be enjoyed at this point with its soft texture, or the container may be placed in the freezer for a few hours to harden or ripen to a firmer texture.

The Other Stuff - The ingredients list on commercial ice creams sport words like monoglyceride glycerol monosterate, guar gum, carageenan, methylcellulose, xanthan gum, etc.,etc.  These additions are food chemists' attempt to imitate a natural texture and mimic the butterfat feel in our mouths.  "Economy ice creams" can be up to half air and as little as 10% butterfat.  This strategy forces the use of stabilizers and emulsifiers to create a desirable product.  With homemade ice cream, we get to skip all these additives.

Making homemade ice cream is easier and less expensive than you might think, and today's machine options facilitate a nearly foolproof result:

Ice Cream Makers - There are three basic types of freezing mechanisms: (1)  ice and salt, (2) pre-frozen inserts, and (3) compressor units.

Ice and Salt - This method may be the most familiar to the old pros among us.  A specialized bucket is outfitted with an internal, metal, cylindrical container designed to seal the ice cream mixture and set in the center of the bucket.  The cylinder is surrounded by alternating layers of ice and rock salt.  The salt melts the ice to an efficient liquid that has a temperature below the freezing point.  A hand or electric-powered crank fits on top of the cylinder and bucket, and turns the internal paddle.  The coldness of the ice slurry transfers through the metal container to freeze the ice cream mixture.

Prefrozen Inserts - Several designs of ice cream makers utilize a pre-frozen insert.  These reusable inserts are sealed, double-walled, metal containers with liquid inside.  The insert is frozen ahead of time, then assembled with a hand or electrical cranking system.  The cold transfers from the frozen liner similarly to the old-fashioned ice and salt method.  One insert will make one batch of ice cream, then will need to be refrozen.  Many fans choose to have an extra insert available, and at least one in the freezer at all times.

Compressor Units - Serious ice cream aficionados may wish to consider free-standing freezing units.  These machines generate the cold, freezing temperatures with a compressor-based system similar to a refrigerator's freezing system.  The machine has a container for the ice cream mixture, an internal paddle, and a continuous freezing element.  Batch after batch of ice cream may be made without any refreezing of an insert, or replacement of ice and salt.

Scoops, Spades, and Spoons - Whatever your frozen pleasure, dishing it up has bent more than one spoon at some point in time.  Great scoops and spades in all colors and shapes are available to easily handle the task.  Personalize your choice by finding a scoop that fits your hand, leverages your arm muscles, and thermally resists sticking to the ice cream.  Show off your talents by serving up your homemade delight in new ice cream dishes!

A:   Legend has it that the ice cream cone was an invention of convenience at the 1904 St. Louis World's Fair.  The ice cream vendor ran out of ice cream dishes when a nearby waffle vendor came to the rescue with a waffle rolled into a cone shape.  Flat-bottomed cake cones were designed and manufactured in the 1940's for the Dairy Queen chain.
 

Q:   My ice cream has a lot of ice crystals on the surface and an off taste.  What's wrong?

A:   Ice cream's freshness depends on good storage techniques throughout production, shipping, and while at home.  Ice crystals form on the top surface when the ice cream has been exposed to warmer temperatures, and then has been refrozen.  The slightly melted surface separates into water, milk fat and solids.  This situation occurs more quickly for ice creams without stabilizers.  Ice cream easily picks up freezer odors.  If the storage container no longer provides a tight seal, top the ice cream with freezer-grade plastic wrap to decrease odor absorption.

Q:   Is there gelatin in gelato?

A:   No.  Despite the seemingly common word form, the word "gelato" derives from the Italian word for "frozen."  However, gelatin is sometimes found in lesser ice creams as a texture enhancer.  The gelatin absorbs extra water and prevents the formation of large ice crystals.  Most gelatins used in ice cream-making are plant-based rather than traditional animal-based gelatins.

Q:  Can I freeze a container of yogurt and make frozen yogurt?

A:  Not exactly.  A typical yogurt contains too much water and not enough sugar; the result would be rock hard.  You can make frozen yogurt with a combination of plain, whole milk yogurt that has been drained for several hours to remove excess water.  (If you live near a Middle Eastern market, lebane is this thick, drained yogurt).  Add sugar, any desired flavors, and freeze.

Q:  What causes an ice cream headache?

A:   An ice cream headache occurs when intense coldness contacts the roof of your mouth.  That area has nerve endings that signal the brain that it needs to warm up.  Blood vessels in the area dilate immediately in response to the situation.  The dilation creates pressure, or the headache.  Slowing down and taking smaller bites will prevent an ice cream headache.