Plant oil body as an effective improver for surimi-based 3D printing

Plant oil body (POB) is a natural oil droplet in micron- or submicron-scale covered by a specific shell composed of proteins and phospholipids, it has arisen numerous research interests in food industry due to its excellent emulsifying ability and great safety as natural product. In this study, POB has been exploited as an effective textural enhancer in surimi-based 3D food printing, and the underpinned mechanisms were investigated. First, POB with great rheological and emulsifying properties was prepared from peanuts, which behaved as a high internal phase emulsion. Second, for the first time, POB was introduced into surimi-based inks, which was able to facilitate the rearrangement of myofibrillar proteins through emulsification, thus ensuring fidelity and stability of 3D-printed surimi structures. The best printing performance was achieved at 2 % POB addition without compromising the surimi gel properties. However, excessive POB addition resulted in decreased viscosity, printing failure, and deteriorated gel characteristics. Third, a new mechanism was proposed to elucidate the interaction between POB and surimi proteins. On the one hand, POB physically filled in the gaps between proteins to increase the continuity and integrity of the surimi inks, thus improving the printability. On the other hand, POB with active surface altered the surimi protein molecular structure to boost the formation of hydrophobic interactions and disulfide bonds, leading to improved gel properties. Overall, this study demonstrated that POB was an effective improver for surimi-based 3D printing, providing new insights on developing new application of POB in food industry.