Preparation of fatty acid esters of polyol glucosides

Abstract

AbstractStarch is readily converted into glucosides by heating with a polyol, such as propylene glycol or glycerol, for a short time at 125 C in the presence of a catalytic amount of sulfuric acid. The product resulting from the reaction of 3 or more moles of polyol per anhydroglucose unit consists mostly of polyol monoglucosides, which are quite resistant to degradation under alkaline interesterification conditions. Attempts to interesterify the glucosides under the usual conditions employed with fats and oils (methyl esters, 0.1% sodium hydroxide, and temperatures up to 200 C) produced no glucoside esters. However, interesterification proceeded readily at temperatures between 160 and 200 C when 5 to 10% soaps and hydrophilic esters (mixtures containing mono‐ and diglycerides or an ester of diethylene glycol monomethyl ether) were employed. Under pressures low enough to rapidly distill off the freed polyol or alcohol, most reactions could be completed in less than an hour. Good yields of glucoside esters were obtained with starch, glycerol, and fat when the required operations were conducted in sequence in one vessel without intermediate purifications.