Effect of composition and homogenization pressure of chia oil emulsions elaborated by microfluidization

The effect of continuous phase composition and microfluidization pressure on properties of chia oil emulsions was analyzed using a D-optimal combined design. The results indicated that the suggested models were significantly (p ≤ 0.05) fitted for all response variables (emulsion droplet size, ζ-potential, Turbiscan stability index and apparent viscosity) and showed high coefficients of determinations (0.897 - 0.933). The soy protein isolate had the major effect on the evaluated parameters due to their emulsifying property and electrical charge. The microfluidization technology allowed the production of emulsions with a droplet size in the range of nanometers (< 500 nm) and monomodal particle size distribution. The optimum condition to obtain the minimum emulsion droplet size (300.97 nm), ζ-potential (-40.03 mV), Turbiscan stability index (1.06) and apparent viscosity (18.65 mPa•s) was when a chia oil emulsion was formulated with 4.8 % w/w of SPI and 25.2 % w/w of MD, applying high microfluidization pressure (104 MPa).

Keywords: Soy Protein Isolate, Maltodextrin, Microfluidization, Emulsion stability, D-optimal combined design, Chia oil.