Rheological Properties of Five Plant Gums

Quanquan Miao,Xin Gao,Xiaoting Fu,Jiachao Xu,Yujie Cheng,Lei Gao,Huaishi Jiang

doi:10.4236/ajac.2018.94017

Abstract

The rheological properties of five gum solutions (Gum Shiraz, Karaya Gum, Ghatti Gum, Arabic Gum and Gum Tragacanth) have been examined. The five mucilage solutions exhibited non-Newtonian, shear-thinning with thixotropy at higher concentrations (0.5% - 1%, m/v). According to the change of viscosity with increasing temperature, all five gums could be defined as three types: gum tragacanth and gum shiraz have a good temperature stability; karaya gum is affected by temperature obviously; the remaining two gums have a general stability. The viscosity of mucilage solutions (Arabic Gum, Ghatti Gum and Karaya Gum) had an apparent dependence on temperature. The parameter n of Shiraz Gum is the minimum, which means it has the best flow properties. The flow activation energy of karaya gum is 2.683 kcal which is the highest than other gums so that it has a great influence on temperature. The gum solutions’ viscosity had different sensitive degree over tested pH range (pH 2 - 10). Shiraz gum and arabic gum possessed better acid-proof and alkali-proof respectively. The addition of salts (NaCl and CaCl2) led to the reduction of viscosity, which was more sensitive to Ca2+ than to Na+. Both storage modulus G’ and loss modulus G” of all five gums had a dependence on temperature and frequency. These results are potentially useful for the application in the field of food processing.

Highlights

Plant gum has a complex and highly branched structure with a large number of polysaccharides as well as protein and phenolics [1]
This work is to make a guidance for these five plant gums practical application in food processing and application
The remaining four kinds of gum, Karaya Gum sample shows the highest viscosity followed by Arabic Gum and Ghatti Gum and Gum Shiraz shows the lowest apparent viscosity among the tested shear rate range

Summary

Introduction

Plant gum has a complex and highly branched structure with a large number of polysaccharides as well as protein and phenolics [1]. Some researchers have studied the rheological properties of some plant gums like arabic gum [7] and gum tragacanth [8]. There is no research about the reasons that contribute to these different rheological properties among different plant gum. The rheological properties of five plant gums were studied. We selected five plant gums (karaya gum, ghatti gum, shiraz gum, arabic gum and gum tragacanth) to explore the common and specific characteristics between five plant gums. This work is to make a guidance for these five plant gums (karaya gum, ghatti gum, shiraz gum, arabic gum and gum tragacanth) practical application in food processing and application

Methods

Results

Conclusion