Encapsulation of EGCG and esterified EGCG derivatives in double emulsions containing Whey Protein Isolate, Bacterial Cellulose and salt

•EGCG esterification with stearic acid was partial and yielded a mixture of esters.•NaCl (1.6–8 %wt) was added to a 0.8 %wt PGPR-0.25 %wt BC-1 %wt WPI double emulsion.•Droplet size, viscosity and stability of emulsions depended on salt concentration.•Storage reduced EGCG and esterified EGCG encapsulation in the 4.3 %wt NaCl emulsion.•Neither of the catechins made the emulsion more resistant to oxidation.