Particle-based food systems subject to lipid migration – A review of measurement, modelling, and mitigation approaches

Many consumer food products such as confectionary or culinary seasonings are particle-based systems containing varying amounts of lipids such as oils, fats, and greases. Lipid migration is the result of inherent metastability of multiphasic particulate food systems. Lipid instability is further aggravated by climatic conditions, interaction with packaging, porosity, material transitions, and even gravity. Resulting lipid mobility can lead to various quality defects such as fat bloom on chocolate or oil stains on fibrous paper-based wrappers. This review revisits the factors influencing lipid migration and the generally accepted transport mechanisms diffusion and capillary flow. The most common measurement methods and modelling approaches described in the literature are discussed and assessed. Modern mitigation strategies to control lipid mobility are reviewed, with discussion on applicability to different particle-based food types and structures. Current trends towards healthier diets, clean-label recipes and sustainable packaging challenge traditional methods to stabilise lipids in food. As such a fundamental understanding, and measurement, modelling and mitigation strategies of lipid migration are highly relevant for a wide range of lipid-containing particulate foods. • Two thirds of consumer foods are sold in particle-based forms and contain lipids. • Oil, fat and grease are subject to migration within and out of the particle system. • Lipid leaking results in quality defects on the food surface and the packaging. • Modern migration measurement techniques, diffusion and capillary models are reviewed. • Innovative oil stabilisation strategies for particulate foods types are discussed.