scholarly journals Rheological Properties of Cassava Starch Film Forming Solution with Kaffir Lime Oil

2019 ◽  
Vol 8 (4) ◽  
pp. 6781-6786

Biopolymer film has attracted interest in food preservation and packaging. In order to obtain biopolymer film of good characteristics, rheological properties of film forming solution is important. In this study, the rheological properties of cassava starch film forming solution incorporated with kaffir lime oil were determined. The flow behavior measurement was made at shear rate of 0.1 to 100 s -1 and 25 C, whereas the effect of temperature on viscosity was measured at 25 to 70 C and shear rate of 10 s-1 . The flow behavior was well described by power law or Ostwald de Waele model. The film forming solution showed flow behavior index (n) in the range of 0.20 to 0.72 which belonged to a non-Newtonian or pseudoplastic behavior. The shear stress increased with increasing shear rate and temperature. The dependency of temperature on viscosity was described by Arrhenius model which allowed the determination of activation energy (Ea ). The Ea of the film forming solutions range between 4.92 to 13.23 kJ mol-1 . The rheological properties obtained in this study provide a basis to correlate the film forming solution properties to the characteristics of the produced biopolymer film.

Author(s):  
Zurriye Yilmaz ◽  
Mehmet Dogan ◽  
Mahir Alkan ◽  
Serap Dogan

In the food industry, rheological properties, such as viscosity, shear rate, and shear stress, are the most important parameters required in the design of a technological process. Therefore, in this study, we determined the flow behavior and the time-dependent flow properties of Turkish Delight (TD) in the temperature range of 25-75°C using a capillar rheometer. The structure and thermal properties of TD were investigated by XRD and a simultaneous DTA/TG analysis. The shear rate values ranged from 5 to 300s-1. We found that: (i) TD behaved as non- Newtonian pseudoplastic foodstuff; (ii) while the measurement temperature increased, viscosity decreased; and (iii) TD was a rheopectic material. The effect of temperature on viscosity was described by means of the Arrhenius equation. The activation energies for the flow of pseudoplastic TD varied from 50.1-74.2 kJ/mol, depending on shear rate. Three models were used to predict the flow behavior of TD, namely, the Power law, Bingham and Casson models. The Power law model adequately described well the flow behavior of TD at different temperatures.


Author(s):  
Florina A. SILAGHI ◽  
Alessandro GIUNCHI ◽  
Angelo FABBRI ◽  
Luigi RAGNI

The control of ice cream powder mixture production is carried out evaluating the ice cream liquid phase. The present study was conduced on ice cream and unfrozen liquid phase in order to indirectly evaluate the rheological properties by measuring the powder mixture. The calibration set was formed by samples with different percentage of thickeners, maintaining constant the concentration of the other remaining compounds. After the NIR acquisitions the powders were mixed with warm milk, blended and than settled in order to obtain the unfrozen liquid phase needed for the rheological measurements. For each recipe three batches were prepared. The flow curves were evaluated by using the Ostwald de Waele’s equation and the goodness of fit was evaluated by the R2, which was above 0.95. Predictive models of rheological parameters were set up by means of PLS regressions in order to predict the consistency coefficient (K) and the flow behavior index (n) from spectral acquisitions. High correlation of calibration was found for both parameters and NIR spectra obtaining R2 of 0.884 for K and 0.874 for n. The good prediction of the models encourages applying them to reduce significantly the time of the powder mixing control during production.


2019 ◽  
Vol 33 (05) ◽  
pp. 1950014 ◽  
Author(s):  
A. Bindu Madhavi ◽  
S. Sreehari Sastry

Rheological properties of Cholesteryl n-valerate, Cholesteryl decanoate and Cholesteryl myristate which are esters of cholesterol have been studied. Phase transition temperatures and rheological parameters such as viscosity, elastic modulus G[Formula: see text], loss modulus G[Formula: see text] as functions of temperature, shear rate and time are investigated. In frequency sweep test, a higher transition crossover region has occurred for Cholesteryl myristate, whereas for Cholesteryl n-valerate a frequency-independent plateau prevailed for both the moduli. The occurrence of blue phase in Cholesteryl decanoate during temperature sweep measurements is an indication for the rheological support. The results for steady state have informed that cholesteric esters are having non-Newtonian flow behavior in their respective cholesteric phases. The power-law model has explained well the shear rate dependence of shear stress. A few practical applications of these esters as lubricant additives are discussed, too.


2012 ◽  
Vol 430-432 ◽  
pp. 301-305
Author(s):  
Li Wen Tan ◽  
Dong Mei Xu ◽  
Quan Ji ◽  
Bing Bing Wang ◽  
Yan Zhi Xia

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.


2013 ◽  
Vol 2 (2) ◽  
pp. 167 ◽  
Author(s):  
Zhen Ma ◽  
Joyce I. Boye

Significant opportunities exist for using pulses in the development of health promoting foods as consumers increasingly look for functional foods with disease prevention qualities. Pulse ingredients could be considered for use in the development of novel, value-added products such as salad dressing. In this study, the rheological properties, color, physical stability, and microstructure of model salad dressing emulsions supplemented with various types of pulse flours (red lentil, green lentil, desi chickpea, kabuli chickpea and yellow pea) were evaluated. Supplementation with pulse flours significantly increased (<em>P</em> &lt; 0.05) the consistency coefficient (<em>m</em>) and decreased (<em>P </em>&lt; 0.05) the flow behavior index (<em>n</em>) of the control dressing in accordance with the power law modelduring steady state flow tests. The pulse-supplemented dressings also showed increased recoverable strain (i.e., increased <em>Q(t)</em>% values) compared with the control. The observed rheological results were supported by scanning electron microscope (SEM) observations, where a more compact and uniform network was observed for supplemented dressings in comparison with the control sample. Addition of pulse flour increased the physical stability of the salad dressing emulsions and also modified color by increasing yellowness and redness hues depending on the type of flour used. This study, thus, demonstrated that pulse flours hold promise as ingredients that could be used in salad dressing formulations.


2016 ◽  
Vol 12 (3) ◽  
pp. 4322-4339
Author(s):  
Salah Hamza

Knowledge of rheological properties of polymer and their variation with temperature and concentration have been globally important for processing and fabrication of polymers in order to make useful products. Basheer et al. [1] investigated, experimentally, the changes in rheological properties of metallocene linear low density polyethylene (mLLDPE) solutions by using a rotational rheometer model AR-G2 with parallel plate geometry. Their work covered the temperature range from  to  and  concentration from  to . In this paper, we reconsider Basheer work to describe the rheological behavior of mLLDPE solutions and its dependence on concentration and temperature.Until now, several models have been built to describe the complex behavior of polymer fluids with varying degrees of success. In this article, Oldroyd 4-constant, Giesekus and Power law models were tested for investigating the viscosity of mLLDPE solution as a function of shear rate. Results showed that Giesekus and power law models provide the best prediction of viscosity for a wide range of shear rates at constant temperature and concentration. Therefore, Giesekus and power law models were suitable for all mLLDPE solutions while Oldroyd 4-constant model doesn't.A new proposed correlation for the viscosity of mLLDPE solutions as a function of shear rate, temperature and concentration has been suggested. The effect of temperature and concentration can be adequately described by an Arrhenius-type and exponential function respectively. The proposed correlation form was found to fit the experimental data adequately.


2018 ◽  
Vol 34 (6) ◽  
pp. 887-928 ◽  
Author(s):  
Ajay Sujan ◽  
Raj K. Vyas

Abstract Gas holdup is one of the most important parameters for characterizing the hydrodynamics of bubble columns. Modeling and design of bubble columns require empirical correlations for precise estimation of gas holdup. Empirical correlations available for prediction of gas holdup (εG) in various non-Newtonian systems for both gas-liquid and gas-liquid-solid bubble columns have been presented in this review. Critical analysis of correlations presented by different researchers has been made considering the findings and pitfalls. As the magnitude of gas holdup depends on many factors, such as physicochemical properties of gas and/or liquid, column geometry, type and design of gas distributors, operating conditions, phase properties, and rheological properties, etc., all of these have been discussed and examined. In order to emphasize the significance, relative importance of parameters such as flow behavior index, consistency index, column diameter, gas flow rate, and density of aqueous carboxymethylcellulose (CMC) solution on gas holdup has been quantified using artificial neural network and Garson’s algorithm for an experimental data set of air-CMC solution from the literature. Besides, potential areas for research encompassing operating conditions, column geometry, physical properties, modeling and simulation, rheological properties, flow regime, etc., have been underlined, and the need for developing newer correlations for gas holdup has been outlined. The review may be useful for the modeling and design of bubble columns.


2020 ◽  
Vol 11 (3-4) ◽  
pp. 49-63
Author(s):  
Soumia Zaim ◽  
Omar Cherkaoui ◽  
Halima Rchid ◽  
Rachid Nmila ◽  
Reddad El Moznine

The rheological properties and spectrum infrared of polysaccharides extracted from Cystoseira myriophylloides algae were investigated in the concentrations range from 3 to 9% (w/v) and at different temperatures. Results of rheological characteristics in a steady shear rate showed pseudoplastic properties and the dynamic rheological properties showed a fluid-like viscoelastic behavior. The flow and viscoelastic characteristics of polysaccharides were described using the power-law (the Ostwald model). The values of flow behavior index of the sample were close to unity (0.91) for 3% and it decreased up to 0.71 for 9% revealing the shear-thinning (pseudoplastic) nature of these polysaccharides. Moreover, the consistency coefficient increased non-linearly with concentration and it was described by a power law. The flow behavior as a function of temperature was satisfactorily described using the Arrhenius law and the activation energy values were extracted. It decreased from 15.68 and 17.21 kJ/mol when the concentration increased from 5 to 9% (w/v). Additionally, in dynamic rheological measurements, tan δ > 1 and G″ > G′ reveling a shear-thinning behavior. Finally, the analysis of the FTIR spectra of these polysaccharides showed the presence of uronic acid groups. This behavior would suggest that polysaccharides extracted from Cystoseira myriophylloides could be an interesting additive as thickeners.


Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1880 ◽  
Author(s):  
Ahmed Gowida ◽  
Salaheldin Elkatatny ◽  
Emad Ramadan ◽  
Abdulazeez Abdulraheem

Calcium chloride brine-based drill-in fluid is commonly used within the reservoir section, as it is specially formulated to maximize drilling experience, and to protect the reservoir from being damaged. Monitoring the drilling fluid rheology including plastic viscosity, P V , apparent viscosity, A V , yield point, Y p , flow behavior index, n , and flow consistency index, k , has great importance in evaluating hole cleaning and optimizing drilling hydraulics. Therefore, it is very crucial for the mud rheology to be checked periodically during drilling, in order to control its persistent change. Such properties are often measured in the field twice a day, and in practice, this takes a long time (2–3 h for taking measurements and cleaning the instruments). However, mud weight, M W , and Marsh funnel viscosity, M F , are periodically measured every 15–20 min. The objective of this study is to develop new models using artificial neural network, ANN, to predict the rheological properties of calcium chloride brine-based mud using M W and M F measurements then extract empirical correlations in a white-box mode to predict these properties based on M W and M F . Field measurements, 515 points, representing actual mud samples, were collected to build the proposed ANN models. The optimized parameters of these models resulted in highly accurate results indicated by a high correlation coefficient, R, between the predicted and measured values, which exceeded 0.97, with an average absolute percentage error, AAPE, that did not exceed 6.1%. Accordingly, the developed models are very useful for monitoring the mud rheology to optimize the drilling operation and avoid many problems such as hole cleaning issues, pipe sticking and loss of circulation.


2018 ◽  
Vol 61 (3) ◽  
pp. 1113-1120
Author(s):  
Ibrahim Denka Kariyama ◽  
Xiaodong Zhai ◽  
Binxin Wu

Abstract. This literature review was conducted on the physical and rheological properties of animal manure slurries and their applications. The review revealed the importance of these properties in the design of anaerobic treatment plants, pipe systems to transport slurries to treatment and storage units, and other applications and management of raw and treated slurries. The selection of pumping and mixing equipment and their power requirements, the flow behavior, mass, and heat transfer, the quality of mixing, pressure head loss, and other applications of manure slurries are affected by the physical and rheological properties. The review shows that manure slurries generally exhibit non-Newtonian pseudoplastic fluid behavior with a decreasing apparent viscosity as the shear rate increases and that the power law equation can successfully be used to describe the relationship between shear stress and shear rate, especially for low total solids concentrations. Keywords: Animal manure slurries, Apparent viscosity, Non-Newtonian pseudoplastic fluids, Power law equation, Rheological properties.


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