Formulation of food-grade microemulsions with glycerol monolaurate: effects of short-chain alcohols, polyols, salts and nonionic surfactants.

摘要

The formulation of food-grade microemulsions with glycerol monolaurate (GML) for antimicrobial applications was studied. Compositions tested included water, GML, short-chain alcohols (such as ethanol), polyols (propylene glycol and glycerol), salts (organic, such as sodium benzoate, sodium lactate and sodium propionate, and inorganic, such as NaCl) and several nonionic surfactants (including ethoxylated sorbitan esters and sucrose esters (SEs)). The phase behaviour of these systems is discussed with respect to the influence of composition on the degree of oil solubilization in the aqueous phase. Oil solubilization was dramatically improved in the presence of the short-chain alcohols and polyols; organic salts contributed to the improvement of oil solubilization as hydrotropes. Tween 20 had the greatest solubilization effect on the oil, but in the presence of SEs formation of oil-in-water microemulsions was difficult. Viscosity measurements along selected dilution lines indicated that at a certain composition the system inverted from a water-in-oil to an oil-in-water microemulsion.