Emulsifying properties of hydrolysed and low HLB sunflower lecithin mixtures

Most commonly processes for lecithin modification are deoling, fractionation with absolute ethanol to produce phosphatidylcholine or phosphatidylinositol-enriched fractions, or enzymatic hydrolysis of these compounds. These modifications are important for achieving an optimal balance between hydrophilic and lipophilic compounds (HLB) and ensure a good food processing ability. The aim of this work was to improve the O/W emulsifying properties of modified lecithins with low HLB mixing them with hydrolysed sunflower lecithin obtained using a microbial phospholipase A(2) (PLA(2)). Thereby, three modified sunflower lecithins (hydrolysed (HL), deoiled (DSL), and PI fraction (PIf)) were obtained. These modified lecithins and their mixtures were applied as emulsifying agent of coarse and fine O/W emulsions (Phi(m) = 0.3). Stability of different emulsions was evaluated through the evolution of backscattering profiles, particle size distribution, and mean particle diameters. Mixtures with a hydrolysed lecitihin increased the HLB (addition of lysophospholipids) and improved the O/W emulsifying properties of DSL and PIf in each case. Mixtures 0.5:0.5 of DSL/HL or PIf/HL produced a similar behavior than 1% HL emulsions, constituting a good alternative for production of new bioactive agents. Practical applications`:This study deals about the increase of the O/W emulsifying properties and thereby the commercial value of modified sunflower lecithins with low HLB values. The main target of this research work is to contribute with useful information to the food industry.