Whey protein isolate (WPI) shows promise for sustainable food packaging due to its excellent oxygen and oil barrier properties, though its moisture barrier and mechanical strength are limitations. This study enhanced WPI-based bio-composites by incorporating hydrophobic lotus leaf (L) particles and comparing two binders: sodium alginate (S) and Tween®80 (T). Lotus leaf powder reduced water vapor transmission rate (WVTR) by 64%, and the binders further reduced WVTR by up to 46% while increasing tensile strength. Films with T showed improved foldability, thermal stability, and hydrophobicity, with a contact angle over 90°. The optimal film, G20-T-L-GO, contained T as the binder, 20% glycerol, and garlic oil (GO) for antibacterial properties. This film showed antibacterial activity against S. aureus, a 76% WVTR reduction, rapid biodegradation in soil within four days, and dissolution in salt, deionized, and tap water. These features make it a promising option for sustainable, biodegradable food packaging.
