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Food products contain various active ingredients, such as flavors, nutrients, unsaturated fatty acids, color, probiotics, etc., that require protection during food processing and storage to preserve their quality and shelf life. This review provides an overview of standard microencapsulation technologies, processes, materials, industrial examples, reasons for market success, a summary of recent applications, and the challenges in the food industry, categorized by active food ingredients: flavors, polyunsaturated fatty acids, probiotics, antioxidants, colors, vitamins, and others. We also provide a comprehensive analysis of the advantages and disadvantages of the most common microencapsulation technologies in the food industry such as spray drying, coacervation, extrusion, and spray cooling. This review ends with future perspectives on microencapsulation for food applications.

The emulsifier-free emulsion copolymerization of styrene (St) and methyl methacrylate (MMA) in the presence of functional monomer acrylic acid (AA) was carried out in batch process. The kinetics was investigated in detail using model function, Integrated Gamma Function. The morphology and size of particles were monitored continuously by TEM all along the polymerization. It was found that the nucleation, polymerization rate increase with increasing concentration of the functional monomer AA, initiator ammonium persulfate (APS), and polymerization temperature T, and APS plays a predominant role in the particle nucleation process. The particle nucleation stage ceased at about 10% conversion and the steady stage can be extended to about 70% conversion. The particle nucleation is likely to yield primary particle via the mechanism of homogeneous coagulative nucleation and coagulation of the primary particle to yield uniform particles. The particle growth in the postnucleation stage is via a shell growth mechanism.

In this article, PBA/P(MMA–crosslinking agent)-composite particle latexes were prepared by semicontinuous seeded emulsion polymerization. To determine the seed emulsion's saturating capacity of an emulsifier, a mathematical model was built to simulate the changes of the seed PBA emulsion's surface tension with the amount of emulsifier added dropwise. The effects of the emulsifier amount added in the second stage and the addition method on the morphology of the composite particles were studied. The results were shown as follows: If the amount of emulsifier added in one batch to the seed emulsion in the second stage was less than or equal to the saturating capacity of emulsifier of the seed emulsion (Cs), the morphology of the particles was “core–shell”; otherwise, a few particles were of a core–shell structure. However, if shell materials were preemulsified and added dropwise at an appropriate rate, the latex particles were still of a core–shell structure, even when the amount of emulsifier added to the seed emulsion was greater than the Cs. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 969–975, 1998

As one of the microencapsulation technologies in the food industry, the coacervation process has been studied extensively for encapsulating reactive, sensitive, or volatile additives or nutrients, with the purposes of increasing their shelf-life, allowing alternative food processing, masking the taste, or controlling their release. The coacervation process principally consists of three basic steps: emulsification, coacervation, and shell formation and/or hardening. Proteins and polysaccharides are the most widely used wall materials for (micro) encapsulation via coacervation in the food industry, and gelatin is the most common one. Coacervation is a unique encapsulation technology. It offers numerous advantages for protecting high-value and labile functional ingredients including flavors and essential oils, such as mild preparation conditions, high core loading level (up to 99%), high shell integrity, high encapsulation efficiency, and excellent controlled-release characteristics. Coacervation technology has been successfully applied in a few commercial products. This chapter summarizes the most recent progresses in both academic and industrial fields, with a focus on the practical side of coacervation based on commercial examples. It includes shell material selection, coacervation processes, parameters influencing coacervation, and evaluation of coacervates.

Oils rich in omega-3 (n-3) and omega-6 (n-6) polyunsaturated fatty acids (PUFA) are increasingly becoming recognized for their role in reducing the risk of diseases and improving the health and wellbeing of consumers. However, their widespread use in food, feed, and supplement products has been hindered because of their poor compatibility in aqueous-based products and susceptibility to degradative and oxidative reactions, which can lead to off-flavors, off-odors, and loss in bioavailability. Microencapsulation technology offers a means to circumvent these issues, as well as to provide a means for controlled and targeted dose release depending on the design and material used. This chapter will focus on the practical aspects of microencapsulation technologies applied by the food industry for developing omega-3 and -6 PUFA-rich powders, including relevant information on prior art such as expired and current patents and patent applications. Although food applications are targeted specifically, the knowledge given could easily extend to pharmaceutical, supplement, or feed applications.