Research on the rheological behavior of honey is important, as rheological behavior is related to sensorial properties and is essential for product quality control. This research provides important information on how honey is properly produced, packaged, stored, and handled. The rheological properties of honey are influenced by many factors, such as composition and temperature. The composition and properties of honey depend on the type of plants from which bees collect nectar or honeydew, from the geographical origin of the honey and the climatic conditions in which it matures. Viscosity is one of the most important rheological properties of honey, as it affects its quality.
The flow behaviour of honey is most often measured by controlled stress rheometers. Most types of honey exhibit Newtonian behaviour, while some of them are non-Newtonian with shear thinning flow behaviour. The viscosity of these types is usually also time-dependent, i.e.; thixotropic. The reason for such flow behavior is attributed to high molecular weight colloidal substances such as dextran and proteins. Non-Newtonian behaviour can be described by the Herschel-Bulkley model, and thixotropy by the Weltmann model. In addition to colloidal substances, crystals and water content in honey, the viscosity is also affected by temperature. With the Arrhenius model, we can accurately and simply describe the effect of temperature on the viscosity of honey and determine the activation energy, which gives us the information on how sensitive the viscosity of a particular type of honey is to changes in temperature.
With the help of reported studies in the literature, I studied the production and composition of honey, models to describe Newtonian and non-Newtonian behaviour, and models to describe the effect of temperature on the viscosity of honey. Using measurements from published research, I studied what influences flow behaviour and how the viscosity of different types of honey of different geographical origins depends on temperature.
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