The effect of tapioca maltodextrins on the stability of oil-in-water emulsions

The effect of concentration of tapioca maltodextrin with three different DE values on the viscosity, depletion attraction potential (W_dep), rate of coalescence (K_c), and creaming rate of oil-in-water emulsion have been investigated. The relative viscosity and W_dep increased with increasing maltodextrin concentration. Critical flocculation concentration (CFC) of emulsions containing maltodextrin with DE of 16 (DE16), 12 (DE12), and 9 (DE9) were 11, 7, and 5.5 wt%, respectively. At maltodextrin concentrations below CFC, there was no change in K_c and no creaming was observed. At maltodextrin concentrations above CFC, an increase in the concentration of DE9 and DE12 resulted in an increase in K_c until it reached a constant value. K_c values remained to be constant in the concentration range between 30 and 40 wt% for DE9 and that between 35 and 45 wt% for DE12. Further increasing in concentration of DE9 and 12 decreased K_c. K_c of DE16 monotonically increased with increasing concentration from CFC to 50 wt%. The rate of creaming decreased with increasing maltodextrin concentration over CFC until it reached zero. Creaming was not observed at maltodextrin concentrations more than 35 wt% for DE9 and 40 wt% for DE12 whereas DE16 showed creaming at all concentrations above CFC. A maltodextrin with a lower DE inhibited creaming more efficiently than maltodextrin with a higher DE because of higher viscosities. The K_c tended to increase with decreasing DE because the strength of interaction between oil droplets increased.