The Effect of Refrigerated Storage on the Rheological Properties of Three Commercial Mozzarella Cheeses

2008 ◽  
Vol 4 (4) ◽  
Author(s):  
Edward B Muliawan ◽  
Savvas G Hatzikiriakos
Keyword(s):  
Rheological Properties ◽  
Viscoelastic Properties ◽  
Elevated Temperatures ◽  
Maxwell Model ◽  
Model Parameters ◽  
Refrigerated Storage ◽  
Mozzarella Cheese ◽  
Relaxation Dynamics ◽  
Generalized Maxwell Model ◽  
Linear Viscoelastic

The linear and non-linear viscoelastic properties and the effect of refrigerated storage on the rheological properties of three commercial mozzarella cheeses was studied. The linearity of the rheological behavior of mozzarella cheese increases with temperature because of the ability for the cheese to flow easier at higher temperatures as well as the lack of yield stress at elevated temperatures. The generalized Maxwell model parameters obtained from the linear viscoelastic data were found to describe the linear relaxation dynamics of the mozzarella cheese satisfactorily. It is also shown that the damping function of mozzarella cheese, which is a measure of the degree of non-linearity, can be described by a generalized Zapas model. Although, the different commercial mozzarella cheeses do not exhibit linear viscoelastic differences at room temperature, they do show significant differences at 60°C. The effect of refrigerated storage on the linear viscoelastic properties is brand-dependent and indicates structural differences among cheese samples. Finally it is shown that the dynamic moduli decrease with longer refrigerated storage due to proteolysis activities and/or weakening of the casein matrix.

Identification of Viscoelastic Properties of Finite Element Structures With Joints

1997 ◽  
Author(s):  
Torsten Herrmann ◽  
Valdas Chaika
Keyword(s):  
Finite Element ◽  
Viscoelastic Properties ◽  
Sparse Matrix ◽  
Maxwell Model ◽  
Least Square ◽  
Identification Algorithm ◽  
Domain Identification ◽  
Generalized Maxwell Model ◽  
Maxwell Models ◽  
Complex Modal Analysis

Abstract Identification of the damping and stiffness parameters of the composite joints in finite element structures is analyzed. For the modeling of the viscoelastic properties of the joints the classical Voigt-Kelvin and generalized Maxwell model (three parameter solid) are used. A time domain identification algorithm for classically and non-classically damped dynamic systems is developed. It is based on the application of an extended Kalman filter and least square technique. The algorithm uses complex modal analysis and sparse matrix technology. Both force and base excited systems are considered. Experimental verification of the identification results is carried out on a test structure. The accuracy of the modeling of damping in the joint using the Voigt-Kelvin and generalized Maxwell models is investigated.

scholarly journals Transglutaminase Shows Better Functionality on High Digestible, High Lysine Sorghum-Wheat Composite Dough and Bread, Compared to Normal Sorghum-Wheat Composites

2019 ◽  
Vol 7 (6) ◽  
pp. 877 ◽  
Author(s):  
Yunus Emre Tunçil ◽  
Mehtap Fevzioglu ◽  
Seda Arioglu-Tunçil ◽  
Gebisa Ejeta ◽  
Osvaldo H. Campanella ◽  
...  
Keyword(s):  
Rheological Properties ◽  
Phase Angle ◽  
Strain Amplitude ◽  
Viscoelastic Properties ◽  
Elastic System ◽  
Frequency Range ◽  
High Lysine ◽  
Substitution Level ◽  
Linear Viscoelastic ◽  
Dough Rheological Properties

Highly digestible high-lysine (HDHL) sorghum-wheat composites have previously been shown to produce better composite dough and bread compared to normal sorghum-wheat composites. This study aimed to test whether improved HDHL lines can provide further enhanced functionality through the effects of transglutaminase (TG) enzyme to improve dough rheological properties. Sorghum-wheat composite doughs were made using HDHL and normal sorghum flours at substitution levels of 10, 20, and 30%, with and without 0.15% TG. Rheological properties of dough were tested using a mechanical spectrometer at 0.05% strain amplitude (within the linear viscoelastic region) over a 0.01- 50 rad/sec frequency range. A more elastic system was observed in HDHL sorghum-wheat composites above 10% substitution levels compared to normal sorghum-wheat composite dough. Addition of TG to HDHL sorghum-wheat composites resulted in a decrease in phase angle values at all substitution level, indicating that TG increased the dough elasticity. However, TG did not change viscoelastic properties of normal sorghum-wheat composites. Bread from HDHL sorghum-wheat composites had significantly higher (P

scholarly journals Study on High-Temperature Glass Lens Molding Process Using FEM Simulation

2015 ◽  
Vol 9 (1) ◽  
pp. 14-19
Author(s):  
Zhang Xiaobing ◽  
Yin Shaohui
Keyword(s):  
High Temperature ◽  
Fem Simulation ◽  
Maxwell Model ◽  
Relaxation Curve ◽  
Model Parameters ◽  
Molding Process ◽  
Promising Alternative ◽  
Complex Shapes ◽  
Generalized Maxwell Model ◽  
Glass Lens

The glass molding process (GMP) can press glass perform into a shape of finished lens under high pressure and temperature conditions, and it is easy to achieve mass production. So, it has emerged as a promising alternative way to produce complex shapes lens. It is well known that viscoelastic is one important properties of glass at high temperature. In this study, A 4-pair generalized maxwell model was used to express viscoelastic of glass, and model parameters were obtained by fitting the relaxation curve obtained from experiment. The finite element models were established by MSC.MARC, the correctness of the FEM models and its used model parameters were verified by the cylindrical compression experiments. Finally, the simulations of glass lens forming stage were performed under different conditions. Stresses distribution were predicted by FEM, it was found that the maximum stress at the edge of lens, which make lens rupture easily at this zone. It was also discovered that the molding temperature is higher, the less stress, and the molding velocity is higher, the higher stress.

Development of a Sliding Plate Rheometer to Measure the High Frequency Viscoelastic Properties of Polymer Melts

2007 ◽  
Vol 17 (6) ◽  
pp. 62563-1-62563-8
Author(s):  
Chelsea A. Braybrook ◽  
Jennifer A. Lee ◽  
Philip J. Bates ◽  
Marianna Kontopoulou
Keyword(s):  
Rheological Properties ◽  
High Frequency ◽  
Viscoelastic Properties ◽  
Parallel Plate ◽  
Polymer Melts ◽  
Measured Data ◽  
Rheological Models ◽  
Linear Viscoelastic ◽  
Good Agreement ◽  
Sliding Plate

Abstract A newly designed and constructed sliding plate rheometer is used to measure the high frequency (210 Hz) linear viscoelastic properties of two model polymers: polybutene (PB) and polydimethylsiloxane (PDMS). Using well-known rheological models, extrapolations of the viscoelastic measurements obtained on a rotational parallel plate rheometer to a frequency of 210 Hz are used to assess the performance of the high frequency sliding plate rheometer. Good agreement between the extrapolated and measured data demonstrates the ability of the sliding plate rheometer to measure the high frequency rheological properties of both Newtonian and shear-thinning materials.

Generalized Maxwell Model as Viscoelastic Lubricant in Journal Bearing

2011 ◽  
Vol 478 ◽  
pp. 64-69 ◽  
Author(s):  
M. Guemmadi ◽  
A. Ouibrahim
Keyword(s):  
Viscoelastic Properties ◽  
Journal Bearing ◽  
Numerical Solutions ◽  
Hydrodynamic Lubrication ◽  
Maxwell Model ◽  
Load Bearing Capacity ◽  
The Core ◽  
Generalized Maxwell Model ◽  
Computational Code ◽  
Flow Velocity Profile

The hydrodynamic lubrication interest is still of great importance, so that more and more elaborated lubricants are considered. They, however, involve consequently more and more hydrodynamic complexity as a result of the rheological properties of the additives. In our case, we consider lubricants having viscoelastic properties described by a generalized Maxwell model used in the case of journal bearing lubrication. The complexity of the coupled associated equations (momentum and constitutive) to describe the hydrodynamic prevailing in such a geometry requires numerical solutions. Using the commercial Finite Volume software Fluent 6.3 together with an appropriate developed computational code, via UDF (User Defined Functions), we determine the pressure distribution as well as the flow velocity profile and the stress field in the core, the load bearing capacity developed and the attitude angle; all together with the effects of the viscoelastic lubricant parameters (relaxation time and shear viscosity).

Viscoelastic modeling of fiber preform compaction in vacuum infusion process

2017 ◽  
Vol 51 (30) ◽  
pp. 4189-4203 ◽  
Author(s):  
Bekir Yenilmez ◽  
Baris Caglar ◽  
E Murat Sozer
Keyword(s):  
Permanent Deformation ◽  
Maxwell Model ◽  
Numerical Approach ◽  
Coefficient Of Determination ◽  
Model Parameters ◽  
Vacuum Infusion ◽  
Characterization Study ◽  
Generalized Maxwell Model ◽  
Viscoelastic Modeling ◽  
Vacuum Infusion Process

A woven fabric’s compaction was modeled by using five viscoelastic models – Maxwell, Kelvin-Voigt, Zener, Burgers, and Generalized Maxwell – to reveal the capabilities and limitations of the models. The model parameters were optimized by minimizing the deviation between the model results and experimental data collected in our previous material characterization study mimicking different compaction stages (loading, fiber settling, wetting, unloading, and fiber relaxation) that a fiber structure undergoes during vacuum infusion process. Although Burgers and Generalized Maxwell models have the highest performance due to their almost equal coefficient of determination values, they have diverse characteristics in terms of modeling different stages of compaction. Burgers model allowed modeling the permanent deformation in relaxation stage, but failed in modeling permanent deformation in settling stage. Generalized Maxwell model could do the opposite, i.e. failed in the former and could handle the latter. This study’s major contribution is a holistic numerical approach and its conclusions by modeling all stages of the vacuum infusion process instead of one stage at a time, and thus optimizing only one set of model parameters (constants of springs and dampers) since they do not change with time. The numerical results of different models were fit to the results of a specially designed compaction characterization experiments conducted in our complementary study.

scholarly journals The effect of milk fat substitution on the rheological properties of Edam-type cheese

2020 ◽  
Vol 246 (12) ◽  
pp. 2443-2450
Author(s):  
Ryszard Myhan ◽  
Tomasz Jeliński ◽  
Ireneusz Białobrzewski ◽  
Jadwiga Sadowska ◽  
Ewelina Jachimczyk
Keyword(s):  
Stress Relaxation ◽  
Rheological Properties ◽  
Palm Oil ◽  
Milk Fat ◽  
Maxwell Model ◽  
Point Of View ◽  
Rheological Parameters ◽  
Initial Stage ◽  
Generalized Maxwell Model ◽  
Made In

AbstractIn cheese-like products, milk components (in particular fat) are partially or completely replaced with non-dairy substitutes. An attempt was made in this study to determine whether Edam-type cheese can be distinguished from its substitute, where milk fat was replaced with palm oil, based on rheological properties. The rheological properties of Edam cheese and its substitute were analyzed during a 16-week ripening period, based on the results of a stress-relaxation test. The values of the rheological parameters were estimated with the use of the generalized Maxwell model and a non-linear model proposed by the authors, which accounted for the plastic deformation of the analyzed samples. The study revealed that both methods were equally effective in describing the stress relaxation process; therefore, they can be regarded as equivalent. Excluding the initial stage of ripening (which is not important from the consumers’ point of view), the replacement of milk fat with palm oil did not influence the rheological properties of Edam-type cheese and the cheese-like product. In subsequent stages of ripening, no significant differences were found in the rheological properties of both products, which could only be used to evaluate their ripeness.

Sign in / Sign up

Export Citation Format

Share Document