Properties of micro and nano casein capsules used to protect the active components: A review

Abstract

Casein is an abundant, cheap, and easy to modify milk protein, which is useful as a wall material to encapsulate organic and inorganic substances that can be applied to protect, load, and deliver flavorings, phenolic compounds, drugs, or inorganic substances. There are many reviews that have explored casein itself as well as the configuration of micelle structures to load substances, but there is a lack of condensed information about the physicochemical properties of casein capsules and the factors that influence them, such as the type of casein, core material and the methods used to obtain the capsules and characterize them. The aim of this review was to identify trends among the different types of casein proteins that can be used as wall materials for encapsulation, the type of core substances that are encapsulated, the reported size, the encapsulation efficiency, and the characterization methods. It can be assumed that each modification of the casein micelle such as the type of casein, active substance, the proportion of substance, and methods used to encapsulate can produce different results in terms of size, morphology and stabilization. These characterization plays a key role in understanding the physicochemical properties of casein encapsulates. In this review the factors that affect the encapsulation with casein as wall material and the characterization methods are presented.