Evaluation of pineapple peel cellulose nanocrystals/EGCG complexes for improving the stability of curcumin emulsion

作者：Tang, Lu; Huang, Huihua^*

来源：Cellulose, 2022, 29(11): 6123-6141.

DOI：10.1007/s10570-022-04666-8

• (-)-Epigallocatechin-3-gallate
• Curcumin
• Pickering emulsion
• Pineapple
• Cellulose nanocrystals

In this study, in order to minimize the degradation of curcumin, Pickering emulsion with embedded curcumin (PCNCs/EGCG-Cur) was prepared and stabilized by pineapple peel cellulose nanocrystals (PCNCs) and (-)-Epigallocatechin-3-gallate (EGCG). The effect of EGCG on the stability and bioaccessibility of the embedded curcumin in Pickering emulsion was assessed. FTIR, XRD and zeta-potential analysis proved the construction of PCNCs/EGCG structure and CLSM showed typical oil-in-water system of PCNCs/EGCG-Cur. Furthermore, the addition of EGCG affected contact angles of the oil-water interface. 30-day storage period showed that the retained curcumin was about 70.35 +/- 1.06% in PCNCs/EGCG(0.04%)-Cur, while the retention rate was 47.15 +/- 0.98% in the control. PCNCs/EGCG(0.04%)-Cur was the most stable under the conditions of thermal and ultraviolet light treatments with the maximum retention rates of curcumin were 92.20 +/- 1.05% and 93.56 +/- 1.37%, respectively. Moreover, EGCG was found to improve the antioxidant activity of the prepared emulsions. Simulated digestion exhibited PCNCs/EGCG(0.04%)-Cur could improve the bioaccessibility of both EGCG (24.99 +/- 3.29%) and curcumin (35.97 +/- 1.26%). These results are conducive to the further application of EGCG in the emulsified food stabilized with cellulose nanocrystals.