Food processing rheology

J. F. Steffe 1996, Rheological methods in food process engineering 2nd edn, Freeman Press, East Lansing, MI, USA. 

Steffe, J.F. 1996. Rheological Methods in Food Process Engineering, 2nd ed. Freeman Press. East Lansing. Mich. 

J.F. Steffe Rheological Methods in Food Processing, 2nd edition, Freeman Press, 1996... 

Measurement of linear viscolelastic properties is a useful way of gaining information about a food s micro structure and how this influences the food s rheological character (Narine and Marangoni, 1999 Gunsekaran and Ak, 2002). However, many processing operations, and mastication, involve large, rapid deformations during which viscoelastic behavior is nonlinear. 

Rao, M.A. (1999). Rheological behavior of processed fluid and semisolid foods, in Rheology of Fluid and Semisolid Foods Principles and Applications, M.A. Rao (ed.). Chapman Hall, Gaithersburgh, Maryland USA. 

Richmond, P., and Smith, A.C. (1987). Rheology stmeture and food processing. In J. Blanshard and P.J. Lillford (Eds.), Food Structure and Behaviour, Academic Press, New York, pp. 259-283. 

Al-Malah, K.-I.-M., Abu-Jdayil, B., Zaitoun, S., and Al-Majeed-Ghzawi, A. 2001. Application of WLF and Arrhenius kinetics to rheology of selected dark-colored honey. J. Food Process Eng. 24(5) 341-357. 

In addition to relationships between apparent viscosity and dynamic or complex viscosity, those between first normal stress coefficient versus dynamic viscosity or apparent viscosity are also of interest to predict one from another for food processing or product development applications. Such relationships were derived for the quasilinear co-rotational Goddard-Miller model (Abdel-Khalik et al., 1974 Bird et al., 1974, 1977). It should be noted that a first normal stress coefficient in a flow field, V i(y), and another in an oscillatory field, fri(ct>), can be determined. Further, as discussed below, (y) can be estimated from steady shear and dynamic rheological data. 

Rao, M. A, Cooley, H. J., and Liao, H.-J. 1999. High temperature rheology of tomato puree and starch dispersion with a direct-drive viscometer. J. Food Process Eng. 22 29-40. 

Stanley. D. W., Aguilera, J. M., Baker, K. W., and Jackman, R. L. 1998. Structure/propeny relationships of foods as affected by processing and storage, in Phase/State Transitions in Foods Chemical. Rheological and Structural Changes, eds. M. A. Rao and R. W. Hartel, pp. 1-56, Marcel Dekker, Inc., NY. 

Because minerals are an integral part of many enzymes, they play an important role in food processing, e.g., in alcoholic and lactic fermentation, meat aging, and dairy food production. Many compounds used as food additives or for rheological modification of some foods contain metallic cations in their structure. A number of these compounds function as antimicrobials, sequestrants, antioxidants, flavor enhancers, and buffering agents, and sometimes even as dietary supplements (Table 4.4). 

Steffe JF (1996), Rheological methods in food processing engineering. Freeman, East... 

The rheological properties of foodstuffe are important in food process engineering since they are the essential parameters in plant design (pumping requirements, pipe and valve dimensions, and mixing operations, etc.) and in the calculation of basic heat, mass, and momentum transfer (Szczesniak, 1977). 

Most of the studies on heat transfer, with fluids have been done with Newtonian fluids. However, a wide variety of non-Newtonian fluids are encountered in the industrial chemical, biological, and food processing industries. To design equipment to handle these fluids, the flow property constants (rheological constants) must be available or must be measured experimentally. Section 3.5 gave a detailed discussion of rheological constants for non-Newtonian fluids. Since many non-Newtonian fluids have high effective viscosities, they are often in laminar flow. Since the majority of non-Newtonian fluids are pseudoplastic fluids, which can usually be represented by the power law, Eq. (3.5-2), the discussion will be concerned with such fluids. For other fluids, the reader is referred to Skelland (S3). 

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