Rheology and food processing

Whilst the rheology of finished food products is crucial for a successful brand, there are as many rheology problems encountered in manufacturing. These include mixing, pumping, as well as flow in heat exchangers and even atomisation of powder precursors in spray dryers. 

The kind of mixing that can cause a problem is due to severe shear thinning that resembles a yield stress. It is then possible to use the cavern theory approach described in chapter 10. Then we can be assured that the well-mixed zone fills the whole mixer. 

Shear thickening in food systems is found for concentrated starch dispersions. Often in the early parts of the production of a food product, this particular situation is encoimtered, and problems can arise. By following the shear thickening map shown in chapter 15, these difficult areas can be avoided. 

Exercise Using whatever rheometers you have at your disposal, measure the rheological properties of tinned custard. 

There are a number of journals that are primarily concerned with rheology, which you should seriously consider subscribing to  

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