This study examined the stability of liposomes loaded with negatively charged protein (bovine serum albumin, BSA) during in vitro digestion. Zeta-potential and morphology measurements confirmed that BSA-loaded liposomes were successfully prepared, with an encapsulation efficiency of around 34%. The encapsulated BSA and the integrity of the liposomes remained unchanged with time when the liposomes were digested in a simulated gastric environment, suggesting that the liposomal membrane protected the entrapped BSA from pepsin hydrolysis. BSA-loaded liposomes exhibited lower stability in simulated intestinal fluid, as shown by damaged membranes and the release of free fatty acids. Also, lipolysis kinetics revealed that bile salts and ionic strength could facilitate a high level of free fatty acid release. This work further supplemented our knowledge about the effects of gastrointestinal digestion conditions on liposomal properties and provided valuable information for the design of liposome formulations for the food and health care industries.
