scholarly journals Effect of Temperature and Used Ingredients on Rheological Parameters of Pancake Dough

2013 ◽  
Vol 16 (3) ◽  
pp. 63-66
Author(s):  
Peter Hlaváč ◽  
Monika Božiková
Keyword(s):  
Rheological Properties ◽  
Dynamic Viscosity ◽  
Kinematic Viscosity ◽  
Fat Content ◽  
Effect Of Temperature ◽  
Rheological Parameters ◽  
Rotational Viscometer ◽  
Two Samples ◽  
Dynamic And Kinematic Viscosity ◽  
Temperature Dynamic

Abstract This paper presents the selected rheological properties of pancake dough such as dynamic and kinematic viscosity and fluidity. The effect of used ingredients and temperature on rheological properties is investigated. Measurements were performed on three pancake dough samples. In two samples, there was used milk with a different fat content, and in the third sample, all ingredients were in a powder state. A digital rotational viscometer Anton Paar DV-3P was used for measuring the rheological properties. The principle of viscometer measurement is based on the dependence of sample resistance to probe rotation. Results of measurements are shown as graphical dependencies of rheological parameters on temperature. Exponential functions were used to express the dependencies of all rheological parameters on temperature. Dynamic and kinematic viscosity decreased, and fluidity increased with temperature. The highest values of dynamic viscosity were obtained for pancake dough from powder ingredients. A higher fat content of used milk caused higher values of dynamic viscosity.

scholarly journals Influence of Temperature and Storing Time on Selected Red Wine Physical Properties

2016 ◽  
Vol 64 (2) ◽  
pp. 433-439
Author(s):  
Peter Hlaváč ◽  
Monika Božiková ◽  
Zuzana Hlaváčová ◽  
Ľubomír Kubík
Keyword(s):  
Thermal Conductivity ◽  
Kinematic Viscosity ◽  
Red Wine ◽  
Thermal Parameters ◽  
Rheological Parameters ◽  
Short Term ◽  
Rotational Viscometer ◽  
Linear Character ◽  
Different Temperatures ◽  
Dynamic And Kinematic Viscosity

Presented article is focused on red wine rheological and thermal properties. Effects of temperature and short term storage on density, rheological parameters and thermal parameters were investigated. First measurement was done at the beginning of storage and then the same sample was measured again after one week of storing. Density was measured by densimeter Mettler Toledo DM 40 at different temperatures. For dynamic viscosity measurement was used rotational viscometer Anton Paar DV-3P. The kinematic viscosity and fluidity were determined according to the definitions. Thermal parameters were measured by instrument Isomet 2104. Temperature dependencies of wine dynamic and kinematic viscosity had decreasing exponential shape and temperature dependencies of fluidity had an increasing exponential shape. Temperature dependencies of red wine thermal conductivity and diffusivity had increasing linear character. Decreasing polynomial functions were obtained for temperature dependencies of red wine density. The values of dynamic and kinematic viscosity, thermal conductivity and diffusivity, and density of red wine were a little bit higher after short term storing, which can be expressed by changed amount of water caused by evaporation. Due to the same reasons were values of fluidity little bit lower after storage.

scholarly journals Selected Physical Properties Assessment of Sunflower and Olive Oils

2019 ◽  
Vol 22 (3) ◽  
pp. 86-91
Author(s):  
Peter Hlaváč ◽  
Monika Božiková ◽  
Ana Petrović
Keyword(s):  
Physical Properties ◽  
Vegetable Oils ◽  
Dynamic Viscosity ◽  
Kinematic Viscosity ◽  
Rheological Parameters ◽  
Measured Temperature ◽  
Oil Viscosity ◽  
Temperature Range ◽  
Olive Oils ◽  
Two Samples

Abstract Presented paper is focused on comparison of certain physical properties of selected vegetable oils. Physical properties, such as density, dynamic, kinematic viscosity and fluidity, were experimentally determined. All experiments were conducted on two samples of vegetable oils: sunflower and extra virgin olive oils with approximate temperature range of 5–32 °C. Density of oils was determined by oscillation method utilizing digital densimeter Anton Paar DMA 4500M at different temperatures. Dynamic viscosity was measured by means of rotational viscometer Anton Paar DV-3P. The rest of rheological parameters were determined on the basis of their definitions. Obtained results are depicted as graphical dependencies of rheological parameters and density on temperature. These dependencies of vegetable oils on dynamic and kinematic viscosity showed decreasing exponential shape, which is in compliance with Arrhenius equation; temperature dependencies on fluidity showed an increasing exponential shape for both samples. Density dependencies of samples on temperature were characteristic with decreasing linear function within measured temperature range. Similar results were achieved by other researchers. On the basis of measured values, it is evident that dynamic viscosity of extra virgin olive oil shows higher values than sunflower oil viscosity, which is a result of different composition of oils.

Rheological Characteristics of Juniperus drupacea Fruit Juice (pekmez) Concentrated by Boiling

2008 ◽  
Vol 14 (4) ◽  
pp. 321-328 ◽  
Author(s):  
M. Akbulut ◽  
H. Çoklar ◽  
G. Özen
Keyword(s):  
Flow Characteristics ◽  
Shear Thickening ◽  
Solid Content ◽  
Soluble Solids ◽  
Effect Of Temperature ◽  
Coefficient Of Determination ◽  
Rheological Parameters ◽  
Soluble Solid Content ◽  
Rotational Viscometer ◽  
Soluble Solid

Rheological parameters of Juniperus drupacea fruit pekmez were evaluated using a rotational viscometer at 10, 20, 30, 40, and 50 °C and at concentrations of 62.8, 68.9, 72.0, and 75.2% total soluble solids. The flow characteristics of Juniperus drupacea fruit pekmez were described by the power law and Herschel—Bulkley models. The Herschel—Bulkley model was found to be the best to describe the rheological property with the coefficient of determination higher than 0.993. Juniperus drupacea pekmez exhibited a time-independent shear thickening behavior. The effect of temperature on viscosity can be described by means of an Arrhenius equation. Depending on the soluble solid contents, the activation energies for flow of diluted samples vary from 78.23 to 60.38 kJ/mol. The effect of soluble solids on viscosity can be described by an exponential equation. Experimental data were fitted to several models in order to describe the effect of temperature and soluble solid content. The combined effect of temperature and soluble solid content on viscosity was also formulated.

Rheological Properties of Aircraft Grease Containing Nano-Additives

2009 ◽  
Vol 419-420 ◽  
pp. 53-56
Author(s):  
Bao Yu Song ◽  
Qing Xiang Yang ◽  
Feng Zhang ◽  
Dai Zhong Su
Keyword(s):  
Rheological Properties ◽  
Apparent Viscosity ◽  
Shear Thinning ◽  
Nano Particles ◽  
Rheological Parameters ◽  
Nanoparticle Concentration ◽  
Rotational Viscometer ◽  
Shear Rates ◽  
The One ◽  
The Given

The apparent viscosity of aircraft grease with different nano-particles content, temperature and shear rates were studied using a rotational viscometer. The rheological properties of two types of aircraft grease, the basic grease and the one with nano-particles additives, were investigated using a rheometer. The results indicated that the apparent viscosity increases with the increase of nanoparticle concentration with the given ratio of nano-particles added. It was also found that the grease with and without the nano-particles both have yield stresses and clear shear-thinning properties. The shear-thinning phenomenon of the grease containing nano-particles is more evident than that of the basic grease. The experimental results also reveal that the rheological characteristics of both types of grease fall in Herschel-Bulkley class, and the nano-particles have a significant influence on the rheological parameters. At the end, the rheology mechanism was discussed based on the entanglement and orientation theories.

Effect of Temperature on Dynamic Viscosity and Activation Energy of Milk and Acidophilus Milk

2014 ◽  
Vol 1059 ◽  
pp. 53-59
Author(s):  
Peter Hlaváč ◽  
Monika Božiková
Keyword(s):  
Activation Energy ◽  
Dynamic Viscosity ◽  
Arrhenius Equation ◽  
Viscosity Measurement ◽  
Effect Of Temperature ◽  
Rheological Parameters ◽  
Physical Parameters ◽  
Measured Temperature ◽  
Regression Equations ◽  
Increasing Functions

This article is focused on temperature dependencies of rheological parameters as the dynamic viscosity and activation energy of milk and acidophilus milk. Viscosity measurement was performed using a single-spindle viscometer. The relations of dynamic viscosity and activation energy in the temperature range 5–25 oC for milk and acidophilus milk were measured. The relations of all physical parameters of milk to temperature showed the influence of relative fat content. The effect of temperature on milk and acidophilus milk parameters is shown in Fig. 1–4. In the measured temperature interval, dynamic viscosities of milk ranged between 2.0 mPa.s and 1.3 mPa.s, and of acidophilus milk between 443.4 mPa.s and 244.1 mPa.s. Measured relations of dynamic viscosity for milk and acidophilus milk during temperature stabilisation had an exponential decreasing progress (Fig. 1–2), which is in accordance with Arrhenius equation. Temperature dependencies of activation energy are described by linear increasing functions (Fig. 3–4). Obtained values of activation energy were in the range 356.97–1267.70 J/mol for milk and in the range 615.94–2129.96 J/mol for acidophilus milk. The mathematical description of the dependencies is summarised by regression equations 2 and 3. Coefficients of regression equations and coefficients of determination approximately in the range 0.984–0.999 are presented in Table 1.

scholarly journals CRITERIONAL FEATURES OF STRUCTURAL CHARACTERISTICS OF FINE TEXTILE MEAT

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
М. П. Сичевський ◽  
Л Войцехівська ◽  
К В Копилова ◽  
C Б Вербицький ◽  
Ю І Охріменко
Keyword(s):  
Shear Stress ◽  
Rheological Properties ◽  
Maximum Shear Stress ◽  
Fat Content ◽  
Plastic Viscosity ◽  
Poultry Meat ◽  
Rheological Parameters ◽  
Limit Values ◽  
Mechanically Separated Meat ◽  
Minced Meat

Poultry meat mechanically separated from broiler carcasses and compared with minced meat from manual deboning was studied. It has been found that an increase in the free moisture content of mechanically separated meat by 10-15% causes a reduction in shear characteristics by almost 2 times. The shear stress values ​​in hand-rolled meat samples were, on average, 1.3 times higher than in physico-chemically similar samples of mechanically separated meat. The samples of hand-rolled meat differed by 1.4 times the values ​​of plastic viscosity, as well as larger, on average 1.5 times, the values ​​of the coefficient of consistency. A set of rheological parameters and their limit values, close to the characteristics of minced meat from manual deboning, namely: the maximum shear stress (penetration) - from 1.9 kPa to 2.2 kPa; plastic viscosity - from 33 Pa • s to 45 Pa • s; coefficient of consistency - from 1.4 to 1.7. It has been established that the most important factors influencing the difference between the rheological parameters of mechanically separated meat and hand-rolled meat are the fat content and the degree of grinding. The reduction of fat content, processing pressure, as well as the speed of grinding of raw materials allows to bring the rheological characteristics of mechanically separated meat to the characteristics of manual deboning meat. The nature of the change in the rheological properties of meat mechanically separated over time is revealed: during the first stage (lasts about 2-3 hours) the structure remains unchanged, the second stage is the period of growth of all indicators to the maximum value, this is the period of critical aging. Further aging (third period) is characterized by a decrease in the numerical values ​​of all indicators, due to a decrease in the strength of the structure under the action of a complex of microbiological and biochemical processes. The study of the rheological properties of mechanically separated meat of broiler chickens and the comparison of the obtained indicators with the corresponding characteristics of minced meat formed by mincing hand-rolled meat, gave grounds for concluding on the possibility and expediency of mechanically separated meat in meat products.

scholarly journals DEPRESSOR ADDITIVE FOR OIL PUMPING

2021 ◽  
Vol 19 (3) ◽  
pp. 143-149
Author(s):  
Y. B. Ramazanova ◽  
Keyword(s):  
Low Temperature ◽  
Rheological Properties ◽  
Pour Point ◽  
Rheological Parameters ◽  
Rotational Viscometer ◽  
Oil Pipeline ◽  
Positive Effect ◽  
Similar Sample ◽  
Control Samples ◽  
Oil And Oil Products

The purpose of the research was to study rheological properties of Azerbaijani oils from the Sangachali and Muradkhanli fields. In order to improve rheological properties of the oil produced from the Muradkhanli and Sangachali fields, a Russian-made depressant СНПХ -2005 additive was used. To determine the optimal concentration of the СНПХ-2005 and confirm its positive effect on oil and oil products, control samples were prepared with this additive in oil M-8 and the oil from the above fields with the calculation of 0.5 kg/t, 0.8 kg/t and 1.0 kg/t. In parallel, similar samples were prepared with the depressant АзНИИ. The pour points of the samples were investigated at -5 0С, -100С and -200С on the rotational viscometer REOTECT-2. It found that the sample with the СНПХ -2005 additive (at the concentration of 0.8%) in the M-8 oil has a lower pour point (minus 40°C) as compared to a similar sample with the depressant АзНИИ (-32°C). The sample with the depressant СНПХ-2005 (at the concentration of 0.8%) and oil reveals the best rheological properties (minus 38°C versus -30°C). As a result of the studies carried out, it was determined that the introduction of the depressant СНПХ-2005 improves rheological parameters of the oil from the above fields, and thereby makes it possible to refuse additional heating in low temperature areas when pumping oil through the oil pipeline.

Rheological Properties of Two Unvulcanized Rubber Compounds as Determined on an Extrusion and a Rotational Viscometer

1964 ◽  
Vol 37 (2) ◽  
pp. 491-502
Author(s):  
F. E. Devine ◽  
J. A. Ross
Keyword(s):  
Shear Stress ◽  
Rheological Properties ◽  
Extrusion Pressure ◽  
Rheological Parameters ◽  
Shear Stresses ◽  
Extrude Material ◽  
Rotational Viscometer ◽  
Shear Rates ◽  
Rubber Compounds

Abstract The viscometer manufactured by A. Macklow-Smith Ltd., which operates at constant rate of extrusion, is a capillary instrument designed for the determination of flow properties of plastics. The instrument has been used for examining the rheological characteristics of rubber compounds and it has been possible to derive the shear stresses required to extrude material at various shear rates between 2 and 1050 sec−1. The general method of operation of the instrument for this purpose is discussed including the determination of preheat time before extrusion and the aspect of incipient vulcanization in the viscometer during extrusion. The effects of various lengths and diameters of dies on rheological parameters and entrance effects are discussed. An important aspect of the work is the observation of a piston height effect in the extruder barrel. Two different compounded polymers have been examined and in one case, the extrusion pressure was found to decrease with piston height whilst in the other highly elastic material, it was found that as the piston descended, the extrusion pressure increased to an equilibrium value. The importance of this effect in obtaining consistent shear stress data is discussed. Results of the work have been expressed in terms of apparent viscosity and also in terms of the parameters which describe a power law relating shear stress and shear rate within the capillary die. Rheological data have been obtained at various temperatures within the range of processing temperatures of the compounds. The effects on rheological properties of mastication and relaxation time after mastication have been examined. Results have been compared with figures obtained on conventional laboratory viscometers such as the Mooney Plastometer and the Wallace Rapid Plastimeter. A biconical, rotational viscometer has also been used at the lower range of shear rates and the results are compared with those obtained from the extrusion viscometer.

scholarly journals Temperature and storing time influence on selected physical properties of milk and acidophilus milk

2013 ◽  
Vol 61 (6) ◽  
pp. 1589-1595
Author(s):  
Monika Božiková ◽  
Peter Hlaváč
Keyword(s):  
Thermal Conductivity ◽  
Mathematical Description ◽  
Kinematic Viscosity ◽  
Fat Content ◽  
Physical Parameters ◽  
Regression Equations ◽  
Hot Wire ◽  
Thermophysical Parameters ◽  
Wire Method ◽  
Dynamic And Kinematic Viscosity

This article deals with thermophysical parameters as: temperature, thermal conductivity, diffusivity and rheologic parameters as: dynamic, kinematic viscosity and fluidity of milk and acidophilus milk. For thermophysical parameters measurements was used Hot Wire method and for rheologic parameters measurements was used single – spindle viscometer. In the first series of measurements we measured relations between thermophysical and rheologic parameters in temperature range (5–25) °C for milk and acidophilus milk. Relations of all physical parameters of milk to the temperature showed influence of relative fat content. Effect of storage on milk and acidophilus milk is shown in the text. All measured relations for milk and acidophilus milk during temperature stabilisation had linear increasing progress with high coefficients of determination in the range (0.991–0.998). It was shown that increasing relative fat content has decreasing influence on milk thermal conductivity. Relations of rheologic parameters as dynamic and kinematic viscosity to the temperature had decreasing exponential progress, while relation of fluidity to the temperature had increasing exponential shape with high coefficients of determination in the range (0.985–0.994).. Mathematical description of the dependencies is summarised by regression equations and all coefficients are in presented tables.

scholarly journals Temperature Relations of Selected Engine Oils Dynamic Viscosity

2014 ◽  
Vol 17 (4) ◽  
pp. 105-108
Author(s):  
Peter Hlaváč ◽  
Monika Božiková ◽  
Radmila Presová
Keyword(s):  
Dynamic Viscosity ◽  
Effect Of Temperature ◽  
Motor Oil ◽  
Exponential Functions ◽  
Rotational Viscometer ◽  
Engine Oils ◽  
The Third ◽  
Used Oil ◽  
Different Types ◽  
Sample Resistance

Abstract This article focuses on temperature relations of dynamic viscosity for selected engine oils. The effect of temperature on new and used oil dynamic viscosity was investigated. Measurements were performed on three different motor oil samples. All the three motor oil samples were synthetic. The first oil sample was new, the second sample was used for 15,000 km, and the third sample was used for 30,000 km. There were made two measurements of samples in one week. Dynamic viscosity was measured using a digital rotational viscometer Anton Paar DV-3P. The principle of measurement is based on the dependence of sample resistance to probe rotation. The results of measurements are shown as graphical relationships between dynamic viscosity and temperature. Decreasing exponential functions in temperature relationships were used for all the samples. The highest difference between the first and second measurement was observed in the new oil, and very small differences were found in other oils. Due to different types of oils and different stage of usage, the results could not be compared.

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