Bubble-containing food structures

Methods for Creating Bubble-Containing Food Structures... 

A typical characteristic of many food products is that these are multi-phase products. The arrangement of the different phases leads to a microstructure that determines the properties of the product. Mayonnaise, for example, is an emulsion of about 80% oil in water, stabilized by egg yolk protein. The size of the oil droplets determines the rheology of the mayonnaise, and hence, the mouthfeel and the consumer liking. Ice cream is a product that consists of four phases. Figure 1 shows this structure schematically. Air bubbles are dispersed in a water matrix containing sugar molecules and ice crystals. The air bubbles are stabilized by partial coalesced fat droplets. The mouthfeel of ice cream is determined by a combination of the air bubble size, the fat droplet size and the ice crystal size. 

As mentioned above, food systems are complex multiphase products that may contain dispersed components such as sohd particles, hquid droplets or gas bubbles. The continuous phase may also contain colloidally dispersed macromolecules such as polysaccharides, protein and lipids. These systems are non-Newtonian, showing complex rheology, usually plastic or pseudo-plastic (shear thinning). Complex structural units are produced as a result of the interaction between the particles of the disperse phase as well as by interaction with polymers that are added to control the properties of the system, such as its creaming or sedimentation as well as the flow characteristics. The control of rheology is important not only during processing but also for control of texture and sensory perception. 

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