Tree nuts and related seeds such as peanuts and oilseeds contain large numbers of secondary metabolites. These compounds have beneficial qualities for human health and wellness, but the reports on them are scattered. The growing field of metabolomics aims to characterize these compounds in a systematic way so that the mechanism of their formation can be better understood. This review gathers current studies using both targeted and non‐targeted approaches to the analysis of secondary metabolites from tree nuts and related oilseeds. Almonds, Brazil nuts, hazelnuts, macadamia nuts, pecan, pine nuts, pistachios, walnuts, peanuts, rapeseeds, and sesame seeds are included along with some lesser known products. The changes with roasting are also discussed. Phenotypic data of this type is useful for identifying specific genetic markers that could be used for crop improvement. High value crops such as tree nuts, peanuts, and oilseeds would benefit from these advances in the understanding of the development of secondary metabolites as they are crucial to seed development, growth, and characteristic flavors.
Practical Applications: Tree nuts and seeds are sources of high quality protein and oils worldwide. This review gathers information about more recent studies of the secondary metabolites that are present in these products. The identification and understanding of the mechanism of their formation is needed for expanding the role of tree nuts and related seeds in nutrition and health. A critical review allows for the collection of research on this topic to increase access of the results to those in the field who continue to advance these studies.
Nuts and seeds undergo a series of processing steps to produce consumer products. Nuts are harvested from trees, or in the case of peanuts, from plants, either mechanically or by hand. Shelling and cleaning to remove protective outer shells is usually done and then most nuts or seeds are roasted to form desired flavors. Some nuts such as almonds, walnuts, and pecan are often consumed raw. Roasting operations can be either continuous or batch operations. After cooling, nuts are inspected to remove unwanted material and then packaged for retail sale.