Inulin has attracted more attention in the food and pharmaceutical industry due its multi functional properties such as dietary fiber, prebiotic nature, modulation of microbial fermentation, reducing fat and pH reduction these properties have a direct effect on reducing intestinal disturbances, constipation, hyperlipidaemia, hyperglycemia and intestinal cancer (Meyer et al. Due to the β (2–1) linkages, inulin is not digested by enzymes in the human alimentary system, contributing to its functional properties: reduced calorie value, dietary fiber, texturizing agent, encapsulating agent, fat and sugar substitute and prebiotic effects. The fractions with a degree of polymerization lower than 10 referred as short-chained fructo-oligosaccharides and the long-chained molecules referred as inulin. The degree of polymerization of standard inulin ranges from 2 to 60 with an average degree of polymerization is about 12. It is a fructan that is linked by β (2–1) glycosodic bonds and contains either a β-D-fructose or an α-D-glucose at terminal position. Inulin is a heterogeneous collection of fructose polymers. Due to change in osmotic potential without changing the total amount of carbohydrate, plants can withstand cold and drought during winter periods (Vijn and Smeekens 1999). Plants can change the osmotic potential of cells by changing the degree of polymerization of inulin molecules by the process of hydrolysis. Inulin is used for reserving energy as well as regulating cold resistance found in roots and rhizomes in plants and is soluble in water. The Inulin belongs to a class of dietary fibers known as fructans and is a storage polysaccharide present in more than 30,000 species of plants. Inulin is naturally occurring polysaccharides produced by many plants, which includes onion, banana, garlic, wheat, asparagus, Jerusalem artichoke and chicory. The combined effect of temperature and solid content on Newtonian viscosity of inulin solution was described by power law type equation and represented as η = 0.8835* (X s) 0.0731 *Exp(296.410/T), ( r = 0.9538, p < 0.001, rmse% = 0.15) Where η is Newtonian viscosity in mPa s, X s is solid content in % and T is temperature in Kelvin (K). Effect of solid content on Newtonian viscosity was described by linear as well as power law models depending upon the temperature studied. The flow activation energy (E a) of inulin solution was significantly ( p < 0.05) affected by solid content and described by exponential type equation ( r = 0.9646, rmse% = 1.07, p < 0.001). The temperature dependency of Newtonian viscosity of inulin solution was described by Arrhenius equation ( r > 0.88, p < 0.05) and activation energy (E a) for viscous flow was in the range 2.111 to 3.013 kJ/mol depending upon the solid content studied. The investigation showed that the inulin solution behaved like Newtonian liquid and viscosity (η) was in the range 2.0998 to 3.2439 mPa s depending upon the concentration and temperature studied. The rheological parameter shear stress was measured upto a shear rate of 300 s −1 using concentric cylinders attachment by controlled stress rheometer. The rheological properties of inulin solution was investigated at different solid content (X s) ranging from 1 to 12 % at wide range of temperatures ranging from 10 to 85 ☌.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |