Optimization of the microencapsulation of synthetic strawberry flavour with different blends of encapsulating agents using spray drying

Abstract

Microencapsulation, increasingly considered a good alternative for retaining flavours and protecting them from degradation, is destined to have a great impact in the food industry. In the present study, the strawberry flavour was spray dried using different encapsulating agents such as maltodextrins (MDs), modified starch (Hi-Cap), arabic gum (AG), xanthan gum (X) and β-cyclodextrin (β-CD). Mixtures with different concentrations of these carriers were prepared and the stability, apparent viscosity and density were studied. The foam phase varied between 2 and 22%, the apparent viscosity ranged from 0.045 to 1.13 Pa·s and the density was approximately 1280 kg/m3. Those mixtures considered the most suitable were spray dried using 180 °C as inlet temperature, and analyzed by gas chromatography–mass spectrometry (GC–MS). The drying yield varied between 45 and 57%, excluding the blend MDs/X/β-CDs. The blend MDs/Hi-Cap/β-CDs presented the best results in terms of the encapsulation efficiency of volatile compounds. In the case of the moisture content the values obtained ranged from 1.3 to 3.3%. SEM analysis showed that MDs/Hi-Cap/β-CDs and MDs/AG/β-CDs led to the formation of spherical, more homogeneous, and smoother particles. The results indicated that the blend MDs/Hi-Cap/β-CDs exhibited the best properties for encapsulating the flavour, followed by MDs/AG/β-CDs and MDs/X/β-CDs.