Gli Ingredienti del Gelato Artigianale
Ice cream is a mixture of ingredients taken from a liquid state to a paste thanks
to a simultaneous process of freezing and whipping (this process is carried out
in ice cream machines).
Freezing crystallizes the watery part of the mixture, whereas whipping incorporates air
and gives the mixture the typical characteristics of ice cream, in other words,
lightness, creaminess and homogeneity of the ingredients used.
Ice cream has three basic ingredients:
This is the only ingredient that freezes during the freezing process (which is performed by ice cream machines). It also acts as a solvent for the solid substances present in the mixture. The smaller the water crystals, the finer the texture of the ice cream.
Sugar is extremely important because it does not freeze and therefore, by mixing it with water, it is possible to obtain a mixture that even at low temperatures (frozen) maintains its creamy consistency. Therefore, sugar has two functions.
- lowering the freezing point of the mixture. Two water and sugar mixtures, each with a different percentage of sugar, will give different creaminess if placed at a specific negative temperature (for example -10°). The mixture with more sugar will be softer.
Air is not an ingredient of ice cream but is incorporated in the mixture during the freezing process. In technical jargon, this increase in volume is called "overrun". Incorporating air makes ice cream "warmer" to the palate, softer and creamier.
The percentage of air present in ice cream varies depending on the composition of the mixture and the type of machine used to make it. For now, suffice to say that homemade ice cream has a percentage of air of around 30-40%, whereas industrially produced ice cream often reaches 100%. Two different systems can be used to check overrun.
A practical one is to leave a small bowl of ice cream on a table, wait for it to melt and see how much the volume has decreased (if it has halved then the overrun was 100%). Another more technical system involves taking two containers (low and wide) that are the same, filling one with the mixture (not frozen) and the other with ice cream (taking care to fill the containers to the top).
The two quantities (which have the same volume) should be weighed net of the container. The percentage difference represents the overrun. For example, if the mixture weighs 140g and the ice cream weighs 100g, the overrun is 140/100=1.4 or 40%.
To obtain a good product, other ingredients are needed. In fact, by blending the water and sugar mixture and incorporating air we obtain a sweet, fairly creamy product that could already be termed as ice cream. However, by adding other ingredients, it is possible to achieve a superior quality product.
- Fats: favour the incorporation of air that is trapped within the fat molecules. Fat therefore, adds a creamier consistency and leaves a warmer sensation on the palate
- Proteins: create a protective barrier around the fat molecules, trapping air and therefore making the product even creamier. They also absorb a large amount of water.
- Stabilizers: are like sponges that swell up by absorbing the small particles of sugar and water dissolved in them. They therefore, trap water and hinder the phenomenon of the crystallization of free water. They also ensure the mixture remains homogenous because in the absence of stabilizers the mixture would "break up" and lose its creaminess after just a couple of hours.
- Emulsifiers: make it possible to combine the watery part and fatty part, so that the mixture is even more pleasant and homogenous.
- Flavours: these give the mixture a variety of flavours and can derive from fruit, cocoa, natural flavours, semi-finished products, flavouring and lots more besides.
All these ingredients, as well as water and sugar, are present in the ingredients normally used to produce ice cream and they will be listed in chapter 7 below.