Effects of Added Weighting Agent and Xanthan Gum on Stability and Rheological Properties of Beverage Cloud Emulsions Formulated Using Modified Starch

Abstract

Stability of beverage emulsion is measured by the rate at which the emulsion creams, flocculates or coalesces, and is generally dependent on rheology of water phase, difference in specific gravities of the two phases and droplet size/distribution of the emulsion. The effects of weighting agents (sucrose acetate isobutyrate and brominated vegetable oil) and xanthan gum on modified starch-based emulsions were evaluated in this study. Emulsion was formed by addition of 9% coconut oil, in the presence or absence of weighting agents, into the water phase containing modified starch at 10, 12 or 14% without or with the addition of 0.3% xanthan gum. Stabilities of emulsions were evaluated both in the concentrated form used for storage and dilute form used in beverages. The addition of xanthan gum into the water phase decreased the flow behavior index (n) from 0.88 down to 0.31 and increased elastic modulus (G′) over 20 times at elevated frequency (w = 50 rad/s) and elevated the stability of the emulsion. The xanthan gum-added emulsion had smaller particle size and demonstrated 14 and 5 times slower phase separation compared to the emulsions without or with the addition of weighting agents, respectively. When the elastic modulus was larger than the viscous modulus (G′ > G″), the emulsions demonstrated greater stability. In dilute beverage solutions, creaming was observed in the absence of xanthan gum.3 Corresponding

Antioxidant Potential and Emulsifying Properties of Neem (Azadirachita indica, Family Meliaceae) Gum Polysaccharide

“…As shown in Table 3 formulations containing higher concentration of NG shown less creaming as compared to formulation having low NG concentration. Data obtained from different studies also support the gum concentration dependant creaming behavior of emulsions [22,23]. Emulsions prepared with high concentration of gum were found to be more stable and remarkable variation in droplet size were not observed.…”

Evaluation of antioxidants stability by thermal analysis and its protective effect in heated edible vegetable oil

“…SAIB is a mixture of esters of sucrose with a composition approximating the name sucrose diacetate hexaisobutyrate (TAHERIAN; RAMASWAMY, 2007). Sucrose acetate isobutyrate is used as a density-broker brominated vegetable oil, exclusively for non-alcoholic beverages to 15 mg.kg -1 (BRASIL, 1999b).…”

Rheology and Stability of Beverage Emulsions in the Presence and Absence of Weighting Agents: A Review

“…Addition of high molecular weight hydrocolloids capable of modifying the rheological properties of water phase could improve the quality of beverage emulsions. For instance, the addition of 0.3% (w/w) xanthan gum to the emulsions, stabilized by modified starch, could reduce the overall average particle size and polydispersity (an index for the range of particle size distribution), increase the cloudy appearance, and enhance the shelf stability of the beverage emulsions 14,29 . This function is related to the formation of aggregates by xanthan gum and reversible shear thinning viscosity of the emulsions, which in turn helps for a better distribution of coated oil droplets and prevent the droplet coalescence after removal of applied shear via high pressure homogenizer [30][31][32] .…”

“…For example, in a beverage, an oil particle of 0.1 μm in diameter will travel upward 100 times more slowly than a particle of 1.0 μm in diameter having the same density 10 . Therefore, the stability of an emulsion can be enhanced by reducing the droplet size along with increasing density of oil droplet and viscosity of water phase 14 .…”