Effect of homogenization parameters on selected physical properties of lemon aroma powder

• Microencapsulation is a technique of aroma protection.
• Emulsion properties could have effect on physical properties of powders.
• No statistically significant difference was seen in reconstructed emulsion droplets.
• The colour of powders differed statistically in tested group.
• The lowest yield was observed when aroma content achieved highest value.

The aim of this study was to examine the relationship between homogenization parameters of lemon aroma emulsion and selected physical properties of obtained powders. Emulsion was prepared in a high shear homogenizer (10 min, 24,000 rpm) or a two-stage pressure homogenizer (30_10 or 60_20 MPa). A 30% emulsion of maltodextrin and Arabic gum in the ratio 7:1 by mass in water and aroma was prepared. The addition of lemon aroma was 2, 6 and 10% (w/w). It was found that in emulsions an increase of aroma addition caused an increase in diameter from 2.4 to 4 μm for Ultra Turrax high shear homogenization and did not change the diameter size for pressure homogenization. For pressure homogenization similar viscosity values were observed. A different effect was observed for high shear homogenization (31–40 mPa s). Increase in aroma addition caused an increase in viscosity. Moreover, a similar diameter of the aroma phase after reconstitution of emulsion from powder (0.7–1.3 μm) was observed. In powders with an increasing amount of aroma, regardless of homogenization method, an increase in porosity, spread of particle size and total colour differences and also a decrease in loose bulk density, solubility and lightness were observed. The lowest apparent density of powders was found for an emulsion containing 6% aroma. The shape of powder particles did not differ from themselves.