TY - JOUR
T1 - Application of WLF and arrhenius kinetics to rheology of selected dark-colored honey
AU - Al-Malah, Kamal I.M.
AU - Abu-Jdayil, Basim
AU - Zaitoun, Shahera
AU - Ghzawi, Abd Al Majeed
PY - 2001/11
Y1 - 2001/11
N2 - The rheological properties of Common Black Horehound, Globe Thistle, and Squill types of dark-colored Jordanian honey were examined. The types of honey used were identified via assessing the source of nectar using pollen analysis (Melissopalynology). The apparent viscosity, η, was measured as a function of the shear rate, γ̇. In addition, the apparent viscosity was measured, at constant shear rate (6.12 s-1), as a function of shearing time. Newton's law of viscosity (i.e., τ = ηγ̇) was found to adequately (R2 ∼ 0.99) describe the flow behavior of honey samples. The apparent viscosity was found to decrease with temperature, and the temperature dependence of viscosity was contrasted versus both Arrhenius model (η = ηoeEa/RT) and WLF model (η/ηG = 10 ((C1(T-TG)/C2+(T-TG)))). Although Arrhenius kinetics may fit the viscosity versus temperature data for the examined types of honey, nevertheless, it gives a relatively high value of activation energy that is quite comparable with, if not even larger than, that of a typical chemical reaction. On the other hand, WLF-model was found to adequately describe the data while at the same time it gives quite reasonable values of both TG and ηG, which are in agreement with those cited in literature.
AB - The rheological properties of Common Black Horehound, Globe Thistle, and Squill types of dark-colored Jordanian honey were examined. The types of honey used were identified via assessing the source of nectar using pollen analysis (Melissopalynology). The apparent viscosity, η, was measured as a function of the shear rate, γ̇. In addition, the apparent viscosity was measured, at constant shear rate (6.12 s-1), as a function of shearing time. Newton's law of viscosity (i.e., τ = ηγ̇) was found to adequately (R2 ∼ 0.99) describe the flow behavior of honey samples. The apparent viscosity was found to decrease with temperature, and the temperature dependence of viscosity was contrasted versus both Arrhenius model (η = ηoeEa/RT) and WLF model (η/ηG = 10 ((C1(T-TG)/C2+(T-TG)))). Although Arrhenius kinetics may fit the viscosity versus temperature data for the examined types of honey, nevertheless, it gives a relatively high value of activation energy that is quite comparable with, if not even larger than, that of a typical chemical reaction. On the other hand, WLF-model was found to adequately describe the data while at the same time it gives quite reasonable values of both TG and ηG, which are in agreement with those cited in literature.
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U2 - 10.1111/j.1745-4530.2001.tb00548.x
DO - 10.1111/j.1745-4530.2001.tb00548.x
M3 - Article
AN - SCOPUS:0035521468
SN - 0145-8876
VL - 24
SP - 341
EP - 357
JO - Journal of Food Process Engineering
JF - Journal of Food Process Engineering
IS - 5
ER -