There seem to be lots of misconceptions about the ingredients used in making gelato and how they differ from those used for ice cream. Let’s jump right in and clear up the whole situation!
The most common ingredients used in making gelato are milk, cream, sugars, powdered non-fat milk, water, thickeners, and flavoring ingredients.
Milk: In general, milk is the most abundant ingredient in gelato on a weight basis, sometimes accounting for more than 50% of the mix. Milk provides important components to gelato: water, fat (in modest amounts), and nonfat milk solids, which consist of protein and lactose and trace minerals.
Cream: The main purpose of adding cream to gelato is to regulate fat content. Fat impacts mouth feel, traps air bubbles to make gelato soft, and contributes flavor both from the fat itself and because fat is a vehicle for many flavor molecules that do not dissolve well in water.
Sugars: In addition to adding sweetness, sugars are the major determinant of the serving temperature of gelato. Sugars, as the main solid ingredient in most gelati, largely control texture. The predominant sugar in gelato is sucrose, that is, common table sugar. Next in importance are dextrose and fructose. Dextrose is less sweet than sucrose while fructose is much sweeter than sucrose. Both dextrose and fructose lower the serving temperature of gelato. In most instances, sucrose combined with dextrose and/or fructose achieves the desired sweetness and serving temperature.
Powdered Non-Fat Milk: Except for gelato that contains eggs, milk proteins are the predominant emulsifying agent in gelato. An emulsifier helps to keep two ingredients that would otherwise separate mixed together. In the case of gelato those two ingredients are fat and water. Milk does not contain enough milk protein to reach the percentage needed to make gelato. The most common source for the additional protein is powdered nonfat milk.
Water: Comprising 58% to 68% of a gelato mix, most of the water in gelato comes from milk, cream, and fruit. Some gelato formulas call for the addition of plain water to achieve balance or as the base for an infusion or decoction of flavor ingredients.
Stabilizers (Thickeners): Stabilizers thicken the gelato mix, limiting the movement of water. Thickeners are what turn milk and sugar into custard, for example. A thickened mixture is less likely to form large ice crystals. Although eggs were used historically to stabilize gelato, they are no longer commonly used for that purpose. Exceptions include some northern Italian gelato traditions that still include eggs for richness, especially in the city of Bologna, and gelato flavors that benefit from the flavor of eggs. Gelatin and cornstarch have a place in the history of gelato and in some regional styles but are not widely used nowadays. Locust bean (carob) gum and guar gum are now the most common stabilizers used in gelato. Locust bean gum is derived from seeds of the carob tree native to the Mediterranean region. It has been used as a thickener for almost 2,000 years. Guar gum is made by milling the large endosperm of the guar bean, which has been used as food in Southeast Asia for hundreds of years.
Flavoring Ingredients: Ingredients used to flavor gelato should be minimally processed and natural. Common flavoring ingredients include cocoa and chocolate, fresh and dried fruit, nuts and nut pastes, coffee, alcoholic beverages, vanilla beans and extract, herbs, spices, and flowers.
This list of ingredients is not exhaustive but it covers the ingredients used in the vast majority of gelato flavors. Examples of other ingredients used occasionally in making gelato include butter, maple syrup, condensed milk, dulce de leche, honey, mascarpone, ricotta, and some sugars such as glucose syrup and trehalose.
What's NOT Used
Ingredients that are not typically used in artisan Italian gelato include: xanthan gum (E415), carrageenans (E407), sodium alginate (E401), carboxymethylcellulose (E466), and pectin (E440). None of these products qualifies under a strict interpretation of the requirements for artisan Italian gelato because the methods of producing or extracting them render them not natural.
Minimal Processing
As you can see, true artisan Italian gelato is made from just a few ingredients all of which should be minimally processed. Ingredients that are produced or extracted chemically, including those used for flavoring, coloring, stabilizing, and emulsifying, should not be used in a gelato that purports to be artisan. But beware, there are no Gelato Police. If you are uncertain, ask what went into any gelato you didn’t make yourself!