Intermolecular interactions in plant based vs. animal milks: a comparative review

Plant- based milk alternatives are milk analogues manufactured to mimic the emulsion, structural, nutritional, and functional properties of animal milks by combining plant materials extracted from for example, oat or almond, combined with added fats, vitamins, and minerals. Although current research is available on the total content of these milk components, it is not yet clear how molecules in plant- based milks assemble to form the milk- like structures or what the final composition of the products is. Much of the available work involves chromatographic methods, microscopy, gravimetric, and elemental analysis methods. Although confocal microscopy with fluorescence labeling has been used to stain for different molecules in milk, there is little information on its use for inter- molecular interactions. The purpose of this review is to bring together analytical methods used to assess composition and insights on intermolecular interactions in plant- based milk alternatives and the structural arrangement of the molecules in the final products. Confocal microscopy is currently limited to research and development and not routine quality control. There is thus a need for improved standardized methods to investigate milk component molecular interactions to maintain plant- based milk alternative product quality.