scholarly journals The influence of texture improver type and its addition level on rheological properties of goat’s milk yogurt

2007 ◽  
Vol 23 (5-6-2) ◽  
pp. 163-170 ◽  
Author(s):  
J. Domagała ◽  
M. Sady ◽  
T. Grega ◽  
D. Najgebauer-Lejko
Keyword(s):  
Rheological Properties ◽  
Apparent Viscosity ◽  
Sensory Quality ◽  
Rheological Parameters ◽  
Flow Index ◽  
Total Protein Content ◽  
Flow Curves ◽  
Rheological Models ◽  
And Control ◽  
Addition Level

Set yogurt from goat?s milk with addition of two texture improvers DSE 6693 and DSE 6694 from NZMP New Zealand, added in the amount of 1, 2and 3% and control yogurt without addition of texture improvers were produced. In yogurt determined sensory quality, pH, apparent viscosity and rheological properties. Flow curves obtained for produced yogurts were described by three rheological models: Ostwald de Waele, Herschel-Bulkley (H-B) and Casson. Addition of texture improver caused an increase in total solids and total protein content of milk for yogurt. Yogurt with texture improvers gave better sensory quality than control yogurt. The yogurt with 1% addition of DSE 6693 and with 2% addition of DSE 6694 had the best sensory quality. The increase in addition level of texture improvers caused an increase in apparent viscosity, consistency coefficient K, yield stress (except H-B model) and deviation from Newtonian flow (decrease of flow index n). Effect of type of improver was rather negligible, whereas its level addition considerably influenced the evaluated rheological parameters.

INFLUENCE OF OLIVE OIL ON THE RHEOLOGICAL CHARACTERISTICS OF MAYONNAISE

2021 ◽  
Vol 22 (4) ◽  
pp. 40-49
Author(s):  
A.N. Martekha ◽  
◽  
V.N. Andreev ◽  
Keyword(s):  
Olive Oil ◽  
Rheological Properties ◽  
Apparent Viscosity ◽  
Sunflower Oil ◽  
Color Change ◽  
Rheological Parameters ◽  
Flow Index ◽  
Loop Area ◽  
Rotary Viscometer

Rheological properties are an important parameter for the quality of mayonnaise. This article in-vestigated the effect of adding olive oil on the rheological properties and color change of mayon-naise. The influence of the storage time of mayonnaise in the refrigerator on the change in rheo-logical properties was also investigated. Mayonnaise was prepared on a laboratory rotary disperser of the Turrex type with a rotor / stator system with a rotor speed range (10000-30000 rpm) at room temperature. Mayonnaise contains 75% oil with varying proportions of sunflower oil and ol-ive oil. Rheological measurements were carried out on a Brookfield rotary viscometer with con-centric cylinders at temperatures of 10 ° C and 25 ° C. Based on the data obtained, the consistency coefficient of the rheological parameters, the flow index and the apparent viscosity were calculat-ed. The color of the test samples of mayonnaise was measured using a three-color colorimeter. All mayonnaise samples exhibit non-Newtonian pseudoplastic flow with a defined thixotropic loop area. Research results have shown that the addition of olive oil affects the rheological properties and color of mayonnaise. The addition of olive oil to the oil phase of mayonnaise reduces shear stress, apparent viscosity, consistency factor and color change at 25 ° C and 10 ° C. When storing mayonnaise in the refrigerator for 15 days, the rheological parameters change. Sunflower oil may-onnaise (75%) has the highest value (L), which means it is measured instrumentally as the bright-est.

scholarly journals The influence of base oil type on the rheological properties of ecological lubricating greases

Nafta-Gaz ◽  
2021 ◽  
Vol 77 (2) ◽  
pp. 127-135
Author(s):  
Rafał Kozdrach ◽  
Keyword(s):  
Shear Stress ◽  
Shear Rate ◽  
Rheological Properties ◽  
Measurement Data ◽  
Measuring System ◽  
Rheological Parameters ◽  
Flow Curves ◽  
Lubricating Grease ◽  
Dispersion Phase ◽  
Base Oil

The article presents the results of research on the influence the type of base oil in lubricating compositions has on the rheological parameters of selected lubricants. Vegetable, mineral, and synthetic dispersion phases were used to produce lubricating greases. The modified amorphous silica was used as the dispersed phase. However, as a modifying additive was used a substance containing the antioxidants, corrosion inhibitors, and EP/AW additives. The experiments on rheological properties were carried out using a Physica MCR 101 rotational rheometer (manufactured by Anton Paar), equipped with a diffusion air bearing and connected to a pneumatic supply – an oil-free Jun-Air compressor and air drying block. The device is equipped with a Peltier system for temperature control in the range of –20°C to 200°C and an external thermostatic VISCOTHERM V2 system, working in the temperature range of –20°C to 200°C. The rheometer control and measurement data analysis were performed using Rheoplus software. The tests were carried out using a cone-plate measuring system with a shear rate range of 0.01–100 s-1 at 20°C for lubricating compositions prepared on various oil bases. To evaluate the value of rheological parameters, the results of tests of the dependence between shear stress and shear rate (flow curves) were used. For the theoretical determined on the flow curves, the following rheological models were used: Bingham, Herschel–Bulkley, Casson, and Tscheuschner. The values of the shear stress (yield point) in depending on the type of dispersion phase has changed. This proves that the use of a base oil with the appropriate functional properties does not weaken, but reinforces the spatial structure of a lubricating grease. It has an important meaning when selecting construction parameters when designing a central lubrication system with grease made from a vegetable oil base (Abyssinian oil). The rheological properties of the lubricating grease are influenced by the type of base oil and thickener, any additives in the grease, the production technology of the grease, and the conditions in which it is used. The tests revealed an important influence of the base oil on the rheological parameters that describe the behaviour of lubricating compositions subjected to stresses and strains in a lubricating system.

Rheological Properties of Blend Spinning Solution of Sodium Alginate and TiO2 Nanoparticles

2012 ◽  
Vol 430-432 ◽  
pp. 301-305
Author(s):  
Li Wen Tan ◽  
Dong Mei Xu ◽  
Quan Ji ◽  
Bing Bing Wang ◽  
Yan Zhi Xia
Keyword(s):  
Rheological Properties ◽  
Sodium Alginate ◽  
Apparent Viscosity ◽  
Flow Behavior ◽  
Viscosity Index ◽  
Rheological Parameters ◽  
Nano Tio2 ◽  
Flow Behavior Index ◽  
Flow Activation Energy ◽  
Degradation Degree

Rheological properties of blend spinning solution of sodium alginate and TiO2 nanoparticles (SA/nano-TiO2) were investigated. The rheological parameters, structural viscosity index (Δη) and flow activation energy (Eη) of spinning solutions were calculated. The results reported that the blend spinning solutions were non-newtonian fluids. The apparent viscosity, consistency index (k) and Eη increased with increasing nano-TiO2 content in SA spinning solution, but the degradation degree of apparent viscosity decreased, flow behavior index (n) only slightly decreased and the Δη had no significantly change. The apparent viscosity (ηa) of spinning solutions could be regulated by changing temperature under 50oC. Blend spinning solution had good stability and practical applicability.

Effect of glycerol concentration and temperature on the rheological properties of cassava starch solutions

2013 ◽  
Vol 33 (2) ◽  
pp. 141-148 ◽  
Author(s):  
Germán Ayala Valencia ◽  
Ana Cecilia Agudelo Henao ◽  
Rubén Antonio Vargas Zapata
Keyword(s):  
Activation Energy ◽  
Rheological Properties ◽  
Apparent Viscosity ◽  
Weight Ratio ◽  
Exponential Model ◽  
Cassava Starch ◽  
Flow Index ◽  
Glycerol Concentration ◽  
Glycerol Content ◽  
All Solutions

Abstract Glycerol/starch (G/S) solutions were prepared at different concentrations, with a weight ratio of G/S=0.0, 0.1, 0.2, 0.3, 0.4 and 0.5, and rheological properties were analyzed at 30, 40, 50, 60 and 70°C. Power law dependency of the apparent viscosity as a function of the shear rate is the most appropriate model for describing the rheological behavior of cassava starch solutions as a function of glycerol concentrations. All solutions showed a pseudoplastic behavior; the flow index (n) did not show significant changes as a function of temperature and glycerol concentration. However, the apparent viscosity (μa) and the consistency coefficient (K) did show strong variations with temperature and glycerol content. The temperature variation of both μa and K were better fitted to an exponential model type exp(Ea /RT), logμa(K) vs. 1000/T. The activation energy of the K data for the solution without glycerol (G/S=0.0) was 13.64 KJ/mol, and it decreased with increasing the content of glycerol in the solutions, becoming 6.14 KJ/mol for G/S=0.5. On the contrary, the activation energy for the μa data increased when increasing the glycerol concentration. The effect of glycerol concentration was also modeled using polynomial and exponential fittings.

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.

scholarly journals Lab Study on the Effect of Cation Exchange Capacity on Slurry Performance in Slurry Shields

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
By Pinghe Sun ◽  
Binkui Zhao ◽  
Han Cao ◽  
Jingyuan Wang ◽  
Dingqiang Mo ◽  
...  
Keyword(s):  
Cation Exchange ◽  
Rheological Properties ◽  
Cation Exchange Capacity ◽  
Ph Value ◽  
Field Work ◽  
Exchange Capacity ◽  
Rheological Parameters ◽  
Flow Index ◽  
Linear Change ◽  
Design Requirements

Ion stabilizers can enhance the reinforcement slurry effect on the wall and stabilize the wall actively in slurry shields. This paper presents different cation exchange capacities obtained by changing the content of the ion stabilizer (1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5%, 5.0%, 5.5%, and 6.0%) in slurry associated with the basis of the existing slurry formula through the laboratory tests. In order to study the effect of the cation exchange capacity on the performance of slurry properties, the rheological properties of the slurry are analyzed and evaluated by the power law model. Results indicate that the cation exchange capacity of the slurry decreases first and then increases with the increase of the ion stabilizer content. When the content of the ion stabilizer is maintained at 3.50%, the cation exchange capacity reaches the minimum value of 2.92. The filtration volumes, pH values, and rheological parameters of the slurry also indicate an obvious linear change with the change of the cation exchange capacity. The minimum filtration volume is 9.70 mL/30 min when the ion stabilizer content reaches 3.50%. However, the pH value reaches the maximum, that is, 11.34 which is changed from 10, and the change could be considered as a constant value in the field work. When the cation exchange capacity increases, the continuity of polymer structure in the slurry decreases first and then increases, the flow index and consistency coefficient are located within a reasonable range, and the rheological properties of the slurry meet the design requirements of the standards.

scholarly journals Effect of Maltodextrins on the Rheological Properties of Potato Starch Pastes and Gels

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Lesław Juszczak ◽  
Dorota Gałkowska ◽  
Teresa Witczak ◽  
Teresa Fortuna
Keyword(s):  
Rheological Properties ◽  
Apparent Viscosity ◽  
Potato Starch ◽  
Considerable Reduction ◽  
Flow Curves ◽  
Degree Of Polymerisation ◽  
Pasting Characteristics ◽  
Storage And Loss Moduli ◽  
Mechanical Spectra

The study examines the effects of maltodextrins saccharified to various degrees on some rheological properties of potato starch dispersions. Pasting characteristics, flow curves, and mechanical spectra were determined for native potato starch and for its blends with potato maltodextrins having dextrose equivalents (DE) of 10.5, 18.4, and 26.5. The results showed that medium-saccharified maltodextrin (DE = 18.4) gave the strongest effect, manifesting itself as a considerable reduction in the viscosity at pasting, a decrease in apparent viscosity during flow, and a decrease in the storage and loss moduli. Addition of high-(DE = 26.5) or low-(DE = 10.5) saccharified maltodextrins had a markedly smaller effect on the rheological properties of starch. The differences in the effects produced by the maltodextrins are closely connected to the degree of polymerisation of the maltooligosaccharides in the systems.

Rheological Properties of Sodium Metatungstate in Aqueous Solutions

2014 ◽  
Vol 960-961 ◽  
pp. 249-253
Author(s):  
Jian Gang Ku ◽  
Kui He ◽  
Hui Huang Chen ◽  
Wen Yuan Liu
Keyword(s):  
Rheological Properties ◽  
Apparent Viscosity ◽  
Theoretical Basis ◽  
Flow Simulation ◽  
Density Fractionation ◽  
Flow Curves ◽  
Fixed Temperature ◽  
Effects Of Temperature ◽  
Increasing Temperature ◽  
Pseudoplastic Fluids

Sodium metatungstate (SMT) solution is an inorganic heavy liquid which is widely used in density fractionation. However, rheological properties of aqueous SMT solutions have never been fully researched. The objective of the present work was to study the rheological properties of aqueous SMT solutions and effects of temperature and density on the apparent viscosity. The steady flow experimental data was fitted using Herschel-Bulkley model. The results show that aqueous SMT solutions of different density are pseudoplastic fluids and the flow curves of SMT solutions were described by the Hershel-Bulkley equation. The apparent viscosity decreases monotonically with increasing temperature under the same density and increases exponentially with increasing density at the fixed temperature. Rheological properties of aqueous SMT solutions can be applied in the calculation of density fractionation efficiency and provides a theoretical basis for flow simulation.

Characterization of Rheological Properties of Low Density Polyethylene in Torque Rheometers

2013 ◽  
Vol 804 ◽  
pp. 216-221
Author(s):  
Xiao Xia Jian ◽  
Wei Liang Zhou ◽  
Le Qin Xiao ◽  
Xiu Li Hu ◽  
Qi Long Zheng
Keyword(s):  
Rheological Properties ◽  
Apparent Viscosity ◽  
Test Methods ◽  
Low Density Polyethylene ◽  
Rheological Parameters ◽  
Low Density ◽  
Rotor Speed ◽  
Filling Degree ◽  
Polymer Melting ◽  
Power Rate

A method to evaluate the rheological properties of low density polyethylene (LDPE) using torque rheometer was developed and the parameter of Power rate model were obtained by fitting balance torque and balance temperature. The rheological parameters of polymer melts were evaluated on the basis of previous equation by introducing the apparent filling degree in torque rheometer, the results show the temperature compensated torque (Mtc) increase from 5.685 Nm to 6.972 Nm, while apparent filling degree change from 0.65 to 0.85 at the rotor speed of 29.98 rpm. TheMtcalso increase from 2,900 Nm to 3.528 Nm and increase by 0.628 Nm at the rotor speed of 4.985 rpm, while it increase by 1.287 Nm from 5.685 Nm to 6.972 Nm at the rotor speed of 29.99 rpm, which means the higher the rotor speed, the more influence on the torque. The other relative rheological parameters, such as the activation energy (ΔE), the Non-Newton (n), etc., calculated in this model, indicate the effect of apparent filling degree on the polymer melting rheology. The calculated values were compared with those derived from capillary rheolometer, the results show the apparent viscosity decrease with the increase shear rate in exponential function, the change rules of apparent viscosity are good agreement from two kinds test methods.

scholarly journals EFFECT OF HEAT TREATMENT ON THE RHEOLOGICAL PARAMETERS OF BUZACHI OIL

Neft i gaz ◽  
2020 ◽  
Vol 6 (120) ◽  
pp. 109-118
Author(s):  
G.A. GABSATTAROVA ◽  
◽  
L.E. BORANBAYEVA ◽  
ZH.K. NAURUZBEKOV ◽  
Y.V. BLAGIKH ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Rheological Properties ◽  
Pour Point ◽  
Laboratory Experiments ◽  
Component Composition ◽  
Treatment Temperature ◽  
Rheological Parameters ◽  
Main Pipeline ◽  
Flow Curves ◽  
Oil Mixtures

The article is dedicated to experimental study of the effects of heat treatment on the rheological characteristics of oil mixtures transported via the Uzen-Atyrau-Samara main pipeline. The research studied the influence of the component composition of oil to its receptivity of the heat treatment temperature and the optimal treatment parameters within the studied scope were identified. The article presents dependence charts of the oil rheological properties (shear stress, effective viscosity, pour point, plastic viscosity) on the heat treatment parameters and the flow curves of untreated and 110 НЕФТЬ И ГАЗ 2020 6 (120) ТРАНСПОРТИРОВКА treated oil. From the data obtained in laboratory experiments, conclusions on the dependence of rheological properties of the heat treatment parameters are made.

Sign in / Sign up

Export Citation Format

Share Document