Influence of nut structure and processing on lipid bioaccessibility and absorption

Nuts confer significant health benefits, despite their relatively high lipid contents. This has, in part, been related to limited lipid bioaccessibility and lower metabolizable energy than predicted. This review summarizes recent advances in the field relating nut structure, processing, and lipid bioaccessibility. The evidence supports that nut lipid bioaccessibility is critically influenced by particle size, which is also related to the proportion of structurally intact cells. Nut structure in the gastrointestinal tract is determined by type, processing, mastication, and their interactions since texture affects chewing efficiency. Recent work highlights mechanisms contributing to limited lipid bioaccessibility beyond particle size and cell wall structural integrity, and the need to clarify intracellular processes occurring during digestion, e.g., molecular diffusion, oleosome structure, proteolysis, interfacial interactions. Future research should also include a greater variety of nuts and aim to clarify the consequences of limited lipid digestibility and bioaccessibility for a wider range of health-related parameters.