A pellicle is a skin or coating of proteins or cellulose on the surface of meat (e.g. smoked salmon) or fermented beverages (e.g. Kombucha).
Pellicles of protein that form prior to smoking meat (including fish and poultry) allow smoke to better adhere to the surface of the meat during the smoking process. Useful in all smoking applications and with any kind of animal protein, it is best used with fish where the flesh of a fish such as salmon forms a pellicle that will attract more smoke to adhere to it than would be the case if it had not been used.[1][2]
Pellicles of cellulose that form in fermenting beverages, such as SCOBYs, are biofilms that are produced as fermentation takes place.[3]