Impact of Fat and Water Crystallization on the Stability of Hydrogenated Palm Oil-in-Water Emulsions Stabilized by Whey Protein Isolate

The influence of aqueous phase composition (0–40 wt.% sucrose, 0 and 150 mmol kg−1 sodium chloride, NaCl) on the stability of 20 wt.% hydrogenated palm oil-in-water emulsions stabilized by 0.9 wt.% whey protein isolate (WPI) to chilling and freezing was studied. Emulsion stability was measured after emulsions had been cooled to temperatures where (i) only the oil phase crystallized or (ii) both the oil and aqueous phases crystallized. Emulsion stability was assessed by DSC measurements of fat destabilization after cool–heat cycles (−40 to 40 °C or −10 to 40 °C), and by measurements of mean particle size, free oil, gravitational separation, and shear viscosity after isothermal storage (−40 to 37 °C). Sucrose improved emulsion stability to droplet coalescence and gravitational separation, particularly at temperatures where part of the aqueous phase froze. The cryo-protective affect of sucrose was attributed to its ability to increase the amount of unfrozen water (UW), modify ice crystal structure, alter interfacial protein structure, and/or reduce the frequency of droplet–droplet collisions. NaCl promoted emulsion instability, particularly at holding temperatures where the oil was partially crystalline, which was attributed to its ability to facilitate the close approach of droplets by screening the electrostatic repulsion between them. These results have important implications for the formulation of emulsions that are stable to chilling and freezing

Impact of Fat and Water Crystallization on the Stability of Hydrogenated Palm Oil-in-Water Emulsions Stabilized by a Nonionic Surfactant

The influence of (0-40 wt %) sucrose and (0 and 150 mmol/kg) sodium chloride on the physical properties of 20 wt % hydrogenated palm oil-in-water emulsions stabilized by 2 wt % Tween 20 after crystallization of the oil phase only or both the oil and water phases has been examined. Emulsion stability was assessed by differential scanning calorimetry measurements of fat destabilization after cooling-heating cycles and by measurements of mean particle size, percent destabilized fat, and percent free oil obtained from gravitational separation after isothermal storage (at -40 to +37 degrees C). At storage temperatures where the oil phase was partially crystalline and the water was completely liquid, the emulsions were unstable to droplet coalescence and oiling off because of partial coalescence. Both NaCI and sucrose increased the extent of partial coalescence in the emulsions. At storage temperatures where both oil and water crystallized, the emulsions were completely destabilized. The stability of the emulsions to freezing and thawing could be improved somewhat by adding sucrose (\u3e20 wt %). Emulsions stabilized by whey proteins were shown to have better freeze-thaw stability than those stabilized by Tween 20, especially in the presence of sucrose. These results may help formulate food emulsions with improved freeze-thaw stability

Prognostic significance of tumor-infiltrating lymphocytes in predicting outcome of distal cholangiocarcinoma in Thailand

10.3389/fonc.2022.1004220Frontiers in Oncology121004220

Effect of Processing Conditions on the Crystallization behavior and Destabilization Kinetics of Oil-in-Water Emulsions

The objective of this research was to systematically study the effect of processing conditions on the crystallization behavior and destabilization mechanisms of oil-in-water emulsions. The effect of crystallization temperature (T c) and homogenization conditions on both thermal behavior and destabilization mechanisms were analyzed. Results show that the crystallization of lipids present in the emulsions was inhibited when compared with bulk lipids as evidenced by a lower onset and peak temperature (T on and Tp, respectively) in differential scanning calorimetry crystallization exotherms. The smaller the droplet size in the emulsion, the more significant the inhibition (lower T on and T p). Lower values of T on and T p were not necessarily indicators of emulsion stability. Homogenization conditions not only affected the T on and T p of crystallization but also the crystallization profile of the samples. Lipids present in emulsions with small droplets were crystallized and melted in a less fractionated manner when compared to lipids in bigger droplets or even to the bulk lipids. The amount of lipid crystallized as evidenced by enthalpy values, did not have a direct relationship with the emulsions stability. Although enthalpy values increased as T c decreased, the destabilization kinetics did not follow the same tendency as evidenced by back scattering measurements