Pickering oil-in-water emulsions stabilized by carboxylated cellulose nanocrystals – Effect of the pH
Artikel i vetenskaplig tidskrift, 2018

Carboxylated cellulose nanocrystals (cCNC) were prepared by oxidation of microcrystalline cellulose with ammonium persulfate and characterized by AFM. Zeta potential was measured at different pH and ionic strength, in presence of mono- and divalent cations. With a length ranging from 50 to 450 nm and a thickness varying between 20 and 60 nm, the cCNC had a surface charge that appeared to be more sensitive to the presence of divalent cations and exhibited a strong pH dependence. The nanocrystals were capable of forming stable oil-in-water emulsions at three different pH of 2, 4 and 7 with a triglyceride oil. The size of emulsion droplets was dependent on oil and cCNC contents. Emulsification was, however, mainly influenced by the pH of the continuous phase, which can be related to reduction of charge on the cCNC surface with decreasing pH. Responsiveness of emulsions towards pH changes was not as dominant as expected, and lowering of pH did not trigger the release of oil from droplets. This can be explained by the strong adsorption of the cCNC, relatively polar triglyceride oil and the limited possibility to induce desorption of nanocrystals from oil surface.

Stability

Triglyceride oil

Carboxylated cellulose nanocrystals

Pickering emulsions

pH responsiveness

Författare

Veronika Mikulcová

Univerzita Tomase Bati ve Zline

Romain Bordes

Chalmers, Kemi och kemiteknik, Tillämpad kemi

Antonín Minařík

Univerzita Tomase Bati ve Zline

Věra Kašpárková

Univerzita Tomase Bati ve Zline

Food Hydrocolloids

0268-005X (ISSN)

Vol. 80 60-67

Ämneskategorier

Fysikalisk kemi

Pappers-, massa- och fiberteknik

Annan kemi

DOI

10.1016/j.foodhyd.2018.01.034