Showing papers on "Guar gum published in 1975"

Chemistry and Interactions of Seed Galactomannans

Abstract: Publisher Summary This chapter discusses the interaction of galactomannans with other polysaccharides. The general chemistry of the galactomannans has been reviewed by Whistler and Smart and others. The chapter discusses the uses of guar and locust-bean gums in various industrial applications and investigates the structural chemistry of galactomannans, especially as revealed by enzymic studies. Mixtures of locust-bean gum with the non-gelling polysaccharide from Xanthomonas campestris have been shown to interact synergistically to give firm, rubbery gels, whereas the use of the galactomannan from C yamopsis tetragonolobus (guar gum) results only in viscosity enhancement. These interactions are important in many of the industrial applications of galactomannans, and a study of them may also help provide an understanding of the associations among polysaccharide chains, contributing to biological cohesion and texture. The two main groups of galactomannan polysaccharides are those derived from (1) the endosperm of plant seeds, the vast majority of which originate in the Leguminoseae, and (2) microbial sources, in particular, the yeasts and other fungi. D-Mannose and D galactose are also found in numerous other plant polysaccharides—for example, glucomannansm, mannans, and galactans.

Flow Properties of Selected Food Gums

Abstract: The flow properties of aqueous solutions of the food gums furcellaran, guar and xanthan were studied. The study was conducted with a concentric cylinder viscometer over the approximate shear rate range of 50 to 700 s-1, and the temperature range of 25 to 45°C. The ranges of concentrations (w/w, %) employed for the gums were: furcellaran, 0.5 to 1.6%; guar, 0.5 to 2.0%; and xanthan, 0.5 to 1.2%. Time-dependent shear thinning (thixotropic) behavior was noted in the case of furcellaran solutions (0.8 and 1.2%), and shear thinning (pseudoplastic) behavior alone with xanthan and guar solutions. The power law model τ = kγ n and the general Casson flow model τ A -τ 0 A = kγ A ,A were employed to describe the flow behavior. For furcellaran solutions, both the power law and the Casson models were satisfactory for describing the flow behavior. For xanthan and guar gum solutions, the power law model described the flow model over a wide but not the entire range of shear rates, while the general Casson model was satisfactory for the lower concentration solutions. Except at low concentrations* the effect of temperature on the apparent viscosity (at 100 and 500 s-1) was found to be small for all the gums.

Polygalactomannan gum formate esters

Abstract: This invention provides novel guar gum formate esters having a degree of substitution between about 0.01 and 3.0, and further provides a process for producing guar gum formate esters by the interaction of guar gum powder or guar gum splits with concentrated formic acid. The invention process represents a general method for formylation of polygalactomannan gums. The polygalactomannan gum formate esters are useful as flocculants, and as sizing agents for paper and textiles.

Aqueous phenolic resole dispersion containing certain hydroxyalkylated gums as interfacial agents

Abstract: Aqueous phenolic resole dispersions are disclosed. The dispersions are produced in the presence of certain hydroxyalkylated gums, such as hydroxyalkylated guar gum, as interfacial agents.

Microorganisms in gums: V. Degradation of the galactomannans guar gum and locust bean gum by different bacilli

Abstract: The degradation of the galactomannans, guar gum and locust bean gum by 5 different Bacillus species,Bacillus coagulans, B. lentus, B. cereus, B. licheniformis andB. firmus was investigated. All these Bacilli degraded the galactomannans without addition of trace elements or mineral salts after a period of 8 and 14 days respectively.