Evaluation of new methods and measuring systems for characterisation of flow behaviour of complex foods
(2006) In Applied Rheology 16(1). p.19-25- Abstract
- Conventional methods often impose difficulties when measuring the viscosity of fluids containing particles or fibres, e.g. tomato paste or fruit preparations, mainly due to the narrow gaps of the viscometer. In order to solve these problems different geometries have been developed, e.g. different mixer systems and wide gap double concentric cylinders. However, these can not be evaluated assuming a constant shear rate throughout the fluid. In this study, three different kinds of mixer systems have been studied; a small and a large paddle and a helix. For the mixer systems an average shear rate must be determined and a quotient between torque and shear stress must be found. in addition, a wide gap double concentric cylinder (DCC) was... (More)
- Conventional methods often impose difficulties when measuring the viscosity of fluids containing particles or fibres, e.g. tomato paste or fruit preparations, mainly due to the narrow gaps of the viscometer. In order to solve these problems different geometries have been developed, e.g. different mixer systems and wide gap double concentric cylinders. However, these can not be evaluated assuming a constant shear rate throughout the fluid. In this study, three different kinds of mixer systems have been studied; a small and a large paddle and a helix. For the mixer systems an average shear rate must be determined and a quotient between torque and shear stress must be found. in addition, a wide gap double concentric cylinder (DCC) was examined and evaluated using two different methods. When evaluating the mixer systems a method based on the Couette analogy has been used successfully for a number of complex fluids, including prepared sauces and fruit samples containing particles of different size. The DCC has been evaluated using a numerical as well as an approximate method, both giving results of good accuracy. All systems had the limitation that no consistent results were obtained for tomato paste. However, when starch was added to the diluted tomato paste dispersion, satisfying results were once again obtained. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/409818
- author
- Roos, H ; Bolmstedt, Ulf LU and Axelsson, Anders LU
- organization
- publishing date
- 2006
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- food dispersions, tomato paste, rheology, food, double concentric cylinder, Couette analogy, mixer viscometer
- in
- Applied Rheology
- volume
- 16
- issue
- 1
- pages
- 19 - 25
- publisher
- De Gruyter
- external identifiers
-
- wos:000237487600007
- scopus:33645817523
- ISSN
- 1430-6395
- language
- English
- LU publication?
- yes
- id
- 2256762e-10f9-402d-910c-5c43ef8bd2ef (old id 409818)
- alternative location
- http://www.ar.ethz.ch/
- date added to LUP
- 2016-04-01 11:34:10
- date last changed
- 2023-08-31 23:08:57
@article{2256762e-10f9-402d-910c-5c43ef8bd2ef, abstract = {{Conventional methods often impose difficulties when measuring the viscosity of fluids containing particles or fibres, e.g. tomato paste or fruit preparations, mainly due to the narrow gaps of the viscometer. In order to solve these problems different geometries have been developed, e.g. different mixer systems and wide gap double concentric cylinders. However, these can not be evaluated assuming a constant shear rate throughout the fluid. In this study, three different kinds of mixer systems have been studied; a small and a large paddle and a helix. For the mixer systems an average shear rate must be determined and a quotient between torque and shear stress must be found. in addition, a wide gap double concentric cylinder (DCC) was examined and evaluated using two different methods. When evaluating the mixer systems a method based on the Couette analogy has been used successfully for a number of complex fluids, including prepared sauces and fruit samples containing particles of different size. The DCC has been evaluated using a numerical as well as an approximate method, both giving results of good accuracy. All systems had the limitation that no consistent results were obtained for tomato paste. However, when starch was added to the diluted tomato paste dispersion, satisfying results were once again obtained.}}, author = {{Roos, H and Bolmstedt, Ulf and Axelsson, Anders}}, issn = {{1430-6395}}, keywords = {{food dispersions; tomato paste; rheology; food; double concentric cylinder; Couette analogy; mixer viscometer}}, language = {{eng}}, number = {{1}}, pages = {{19--25}}, publisher = {{De Gruyter}}, series = {{Applied Rheology}}, title = {{Evaluation of new methods and measuring systems for characterisation of flow behaviour of complex foods}}, url = {{http://www.ar.ethz.ch/}}, volume = {{16}}, year = {{2006}}, }