Stability and bioaccessibility of lycopene loaded in a Pickering emulsion stabilized by tannic acid-starch complexes:...

Herein, three tannic acid (TA)-starch nanoparticles (corn starch [CS], potato starch [PS], and mung bean starch [MBS]) were fabricated as Pickering emulsion stabilizers. Emulsion-loaded lycopene was prepared using a solution of soybean oil and the three complexes (3:7, v/v). The focus of this study was to evaluate the environmental stability and digestive properties of these emulsions and to reveal the properties of TA/starch complexes and their interfacial structure. Under different environmental stresses, the emulsion size was stabilized at pH 3-7, while the TA/PS emulsion system increased in alkaline conditions (pH 9). In addition, the TA/MBS emulsion system exhibited the highest freeze-thaw stability owing to its higher interfacial load and better emulsifying properties. During digestion, the TA/starch complexes gradually fell from the emulsion interface, resulting in the thinning of the interface film (the emulsion size gradually increased, the size of TA/starch complexes gradually decreased, and the number of complexes first increased and then decreased significantly). The TA/MBS emulsion was partly intact and spherical lipids in the intestinal digestion. In addition, the small droplet size of the emulsion made it effective in improving the release of free fatty acids (TA/MBS = 66.28 %) and the bioavailability of lycopene (TA/MBS [37.38 %] > TA/CS [31.67 %] > TA/PS [25.98 %]). Conclusively, the findings of this study can provide new insights into the structural state and digestion properties of starch and TA, which can help formulate a high-nutrient diet.