Re-Designing Clouds to Increase Turbidity in Beverage Emulsions

Abstract

Clouds represent oil-in-water emulsions, which are used to create a turbid appearance in beverage emulsions. Aim of the present study was to investigate whether crystalline structures at the oil-water interface or a solidified dispersed phase sufficiently increase the refractive index difference between the two phases to create turbidity in a more efficient manner. Bulk materials and dispersions were characterized by differential scanning calorimetry and time-domain-NMR for crystal structure and solid fat content, respectively. Use of high melting emulsifiers (HME), 1% sodium stearoyl lactylate (SSL), 1% glyceryl stearoyl citrate (GSC), respectively 1.5% phospholipid (PL) did not result in an increase in turbidity. Data indicate that the emulsifiers did not crystallize at the interface. However, modification of the dispersed phase with high melting lipids (HML) was successful. Using fats with increasing melting point, it was shown that turbidity increased with increasing degree of crystallinity. Compared to a liquid medium chain triglyceride (MCT) turbidity increased significantly from 290 NTU (ratio) using hydrogenated palm fat (HPF, 400 NTU (ratio)) or tristearin (SSS, 440 NTU (ratio)) instead. In order to induce that effect, a critical degree of crystallinity of more than 36% needed to be achieved.