Mix the egg yolk and the wine vinegar and add salt and pepper. Pastis mayonnaise pastis, breaded chicken sticks with Curly® peanut. On the contrary, a cooling (but not freezing) can stabilize the emulsion. They are very delicate structures and their stability can be affected by the pH, the temperature, the dissolved salts, the agitation and many other factors.īy increasing the temperature, the fats become more fluid and the elements within the emulsion will separate. The stability of emulsionsĪs we said before, the emulsions are very unstable. Lastly, also the gelatin, the common “fish glue” is a good emulsifier.
The proteins (in addition to separating the droplets from the continuous phase) stabilize the emulsion by forming a layer that separates the droplets, preventing their aggregation. They orient the hydrophobic areas towards the fat and hydrophilic areas towards the water. Proteins are excellent emulsifiers and since they are edible, they are widely used in cooking. It is very important not only to obtain the emulsion stability, but also and above all make it last for a long time (a very important aspect in the food industry, in which the stability must be guaranteed for many months). They go between the fat molecules and water, preventing their separation.įor example lecithins, contained in egg yolk and in other foods, even if they do not form very stable emulsions. Therefore, we must prevent the separation of fat and water in order to use the emulsion.įor this reason, an emulsion is produced with the help of molecules with surfactant properties which stabilize the compound. However the main problem of the emulsions is to not be stable for a long time. On the contrary, if the oil molecules are dispersed in water, it is called “ oil in water” emulsion, which are also the most common in the food industry. If the water is dispersed in fat, as in the butter or margarine, it is called “ water in oil” emulsion. However, the molecules of an ingredient ( dispersed phase) are able to go inside the other ingredient ( continuous phase) if they are subjected to a strong stirring.
Obviously, not all substances can mix with each other, in fact some of them remain completely separate.įor example, alcohol and water are mixed in any proportion, while fat and water form two different layers. If the fat is liquid at room temperature, it is commonly called oil. The emulsions contain a fat and water, and of course many other molecules. An emulsion is a dispersion of two liquids that do not mix with each other and there is plenty of these preparations in restaurants.
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