Ice, Cream... and Chemistry - American Chemical Society (2024)

FAQs

What is doubling the amount of air in ice cream? ›

The amount of air added to ice cream is known as overrun. If the volume of ice cream is doubled by adding air, then the overrun is 100%, which is the maximum allowable amount of air that can be added to commercial ice cream. The less expensive brands usually contain more air than the premium brands.

To ensure mixing of fat and non-fat ingredients, emulsifiers are added if they are not already in the ice cream in the form of milk proteins called casein and whey. These emulsifiers connect the fat molecules to the water-based ingredients which normally don't mix.

Ice cream is a type of emulsion, a combination of fat and water that usually wouldn't mix together without separating. However, in an emulsion, the very small droplets of fat are dispersed through the water, avoiding this separation.

Ice cream is a heterogeneous mixture of a liquid and finely dispersed solids. That is why it is called a complex colloidal system. Each part in this system has an important function. Air bubbles typically make up about 30 to 50 percent of the mixture's final volume.

High-quality ice creams have about 25 percent air, while cheaper commercial versions contain between 50 and 90 percent air. Gelato, on the other hand, is churned at a much slower speed, resulting in little air and, consequently, a denser, softer texture.

The amount of air in ice cream is measured as the percentage by which the air increases the volume of the mixture. And this measurement is called the "overrun". So if 1 quart of ice cream mixture becomes 1.5 quarts of ice cream once the machine has finished churning, we say that the ice cream has an overrun of 50%.

Sugar affects the texture by enhancing creaminess and controlling hardness levels. Too much sugar in a recipe can prevent your ice cream from freezing, and too little sugar in ice cream can make it hard. Air keeps ice cream soft and scoopable.

Have you ever bought something with vanilla ice cream in it (like an ice cream sandwich) and found that its edges are tinged yellow. That is because the ice cream at one point was not kept at the proper temperature.

Fat reducing ice cream with inulin

Orafti inulin is an excellent fat replacer in ice cream. Owing to the long chains of inulin, which have low solubility, this ingredient has unique texturising properties. Inulin ensures a smooth texture, mouthfeel, and creaminess comparable to fat.

As the ice cream mixture is cooled down, some of the water freezes and forms ice crystals. The concentration of sugar increases in the rest of the water, lowering the freezing point of the sugar-water solution – just like the salt in the example above. As a result, the ice cream stays soft.

What type of chemical reaction is ice cream? ›

An exothermic reaction is a chemical reaction that releases light or heat, otherwise known as energy . In this case, heat is released from molecules moving around, freezing cream into ice cream! More exothermic reactions include the burning of materials and explosions.

Melting of ice cream is a physical change. Liquid ice-cream solidifies again on freezing without change in chemical properties.

Similar to sugar, salt affects how water freezes and effectively lowers the freezing/melting point of water. Creating a saltwater slush and packing this around our ice cream base allows us to cool the base enough so that it starts to thicken and freeze before the ice melts completely.

Ice cream is considered a mixture. But it is a special type called an emulsion. A mixture, by definition, is a combination of different substances mixed together. Ice cream fits this description since it is made up of milk, cream, sugar, and ice.

Icecream is a heterogeneous mixture because here solid ice (small crystals) are dispersed in a liquid (cream) medium. A heterogeneous mixture is made up of two or more than two substances that remain physically separate.

It makes ice cream softer and creamier. The tiny air cells whipped into the base mix are largely responsible for the general consistency of ice cream, and greatly affect texture and volume of ice cream. The more air bubbles there are and the smaller they are, the smoother the ice cream will be.

Snack foods, ice cream, breakfast cereals

Ben & Jerry's and Häagen-Dazs vanilla ice creams weigh more than 100 grams per half cup (120 grams), so they contain roughly 20% air. Breyers vanilla ice cream weighs 67 grams per half cup, with about 45% of the volume being air.

Overrun is the percentage of air in the ice cream. Around 40% will give you a smooth creamy and heavy enough texture to work best for soft serve. If there is too much air the ice cream becomes pock marked and yellowish and doesn't feel right. Not solid enough.

Air is an essential ingredient for ice creams and more particularly for milk-based ice creams. Without air, our ice creams would look more like ice cubes and would not have this creamy consistency. In pastry world, incorporating air into a preparation is called overrun.