Abstract
Differences in the rheology and friction factor of natural food hydrocolloid gels were studied in this paper. The practical importance of the knowledge of the rheological parameters is quite evident. The experimental data were carried out using a concentric cylinder rotary viscometer. It was prepared 1% hydrocolloid solutions (hydrogels). Hydrogels of the natural gums extracted from the seeds of the plants and plant tubers have been used - carob gum (from the seeds of Ceratonia siliqua), guar gum (from the seeds of Cyamopsis tetragonoloba) and tara gum (from the seeds of Caesalpinia spinosa). Rheological behaviour has non-Newtonian pseudoplastic character and the flow curves were fitted using the Otswald - de Waele (power law) model and Herschel - Bulkley model. The hydrogels exhibit shear thinning behaviour. The meaning of the rheological parameters on the friction factors during flow of hydrocolloid gels in the tube has been shown. Information on time dependent behaviour of tested liquids has been also obtained. Time dependent curves were fitted by the Gaussian model. Preliminary results obtained for a constant shear rate showed the thixotropic and time-dependent behaviour of the hydrogels. These parameters can be especially used in much software dealing with a numerical simulation of the flow problems.
Highlights
The knowledge of the rheological properties of food products is essential for the product development, quality control, sensory evaluation and design and evaluation of the process equipment
Hydrogels of the natural gums extracted from the seeds of the plants and plant tubers have been used – carob gum, guar gum and tara gum
The highest values of the apparent viscosity were achieved for the guar gum solution, following by the tara gum solution and the minimum values exhibited carob gum solution
Summary
The knowledge of the rheological properties of food products is essential for the product development, quality control, sensory evaluation and design and evaluation of the process equipment. The flow behaviour of a fluid can be varied from Newtonian to time dependent nonNewtonian in nature depending on its origin, composition and structure behaviour and previous history (Rao, 2005) The knowledge of this behaviour is very important for natural hydrocolloids owing to an increasing demand on the processed hydrocolloids products. Hydrogels are polymer networks formed from polymers that absorb water to a significant extent (Wientjes et al, 2000; Mandala et al, 2004; Abd Alla et al, 2012) Their porous structure and elastic properties make them useful for applications such as tissue engineering, drug delivery systems and functional coatings (Kono et al, 2014; Jamshidian et al, 2014). Several researchers (Alves et al, 1999; Sandolo et al, 2009; Karaman et al 2014) studied the rheological characteristics of natural hydrocolloids and reported Newtonian as well as time–dependent non–Newtonian flow behaviour of hydrogels (hydrocolloids solutions) (Sandolo et al, 2010)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
