Nutraceutical-fortified plant-based milk analogs: Bioaccessibility of curcumin-loaded almond, cashew, coconut, and oat milks

Plant-based milk analogs often contain oil bodies, which are natural colloidal particles comprising of a triglyceride-rich core coated by a phospholipid/protein shell. Hydrophobic nutraceuticals, such as curcumin, can be encapsulated within these oil bodies utilizing a simple pH-driven method. Previously, we loaded curcumin into the oil bodies in soymilk using this approach. Here, we show this method is highly versatile and can be utilized to incorporate curcumin into other plant-based milk analogs (coconut, cashew, almond, and oat milks). Initially, the impact of pH-driven loading on the physicochemical attributes of the milk analogs was investigated. Curcumin bioaccessibility in the milk analogs was then ascertained using a simulated gastrointestinal tract. Curcumin was successfully loaded into all the milk analogs without causing adverse effects on oil body properties or stability. Curcumin had a high encapsulation efficiency (>86%) in all milk analogs, which was attributed to its localization inside the oil bodies. The curcumin-loaded plant-based milks had fairly similar bioaccessibilities (>60%), which were much higher than those seen for a crystalline form of the curcumin (about 5%). The information obtained may be utilized to facilitate the creation of the next-generation of nutritionally fortified plant-based milk analogs.