Textures

With gelatin, unique and tailored textures can be created. Just think of those clear gummy candies made from gelatin: the gum-like elastic texture, its characteristic bite and that typical melting behavior can only be achieved with gelatin. Foamed textures can also be formed with gelatin: marshmallows and chewy candies just wouldn’t be possible without it. Even in fat-reduced products and spreadable sausages, gelatin can create a smooth, creamy texture and a rich mouthfeel. In dairy products, gelatin enables a variety of consistencies to be created – from creamy to firm – and, at the same time, prevents syneresis. In cakes and pastries, powdered gelatin and leaf gelatin are used to texturize fillings. It creates a wonderfully creamy mouthfeel and also improves the stability and sliceability of whipped fillings.

Gel

Gel formation, viscosity and texture are closely related properties, determined mainly by the structure, molecular size and temperature of the gelatin. Being a mixture of polymer chains of different lengths, gelatin forms colloidal solutions or sols. On cooling, these sols convert to gels; on warming, they revert to sols. This unlimited reversibility of the gelling process is an extremely important technological property of gelatin.

Foam

With its excellent foam building properties, gelatin can also be used to incorporate air into multi-phase emulsions through whipping or gas injection – from marshmallows and mousse desserts to cheese preparations. Gelatin decreases the surface tension of the water, facilitating foaming. Within the foam, the gelatin binds the water during the gelling process and surrounds the fat globules with a thin film. As such, it also stabilizes the foam. Large amounts of air are retained in the product, and different bubble sizes mean that a range of textures can be produced, from creamy to fluffy. Thanks to gelatin’s gelling and stabilizing properties, product texture is maintained, even during lengthy periods of storage.

In the case of marshmallows or aerated chews, gelatine prevents the recrystallization of sucrose. The ability to form and stabilize foams comes from the surface properties of gelatine: they are based on the fact that the gelatine side chains have charged groups and that certain parts of the collagen sequence contain either hydrophilic or hydrophobic amino acids. Both tend to migrate towards surfaces reducing the surface tension of aqueous solutions.