A rarely used option for reduction the size of Ca‐alginate beads is the jet cutter, a rotating disk coupled to the output of the nozzle, and responsible for cutting the jet in smaller sizes. There are few systematic studies in the literature about this apparatus and its operational effects on the bead size. Therefore, this work aimed to investigate some operational parameters on the size of Ca‐alginate beads produced by dripping and jet cutting methods. First, physicochemical properties of different concentrations of sodium alginate solutions were determined, and the viscosity of 0.92 Pa s, corresponding to 2% (wt/wt), was found to be optimum for bead formation. For the dripping process, the highest flow rate of the alginate solution (49 mL/min) caused a limited reduction of bead size to 2 mm. This study on drop formation demonstrated that models developed for size prediction cannot be used as a tool for determination of size, due to the possible influences of the viscous forces. The jet cutter, adapted to a continuous jet regime, allowed to reduce from 5.2 mm to less than 1 mm in size with the increase of the rotation speed from 200 to 900 rpm. However, this increase resulted in higher tangential velocity of the beads, requiring larger collect recipients. This study developed the basis for broadening the application of the jet cutter to different biopolymers and ensures a better performance of this system. Practical applications The technology of microencapsulation consists in the incorporation of a compound within a matrix, and it has been often used in the food industry by solving several limitations, allowing the immobilization, protection, controlled release of some ingredients, and changing of product properties. The use of biopolymers, such as sodium alginate, associated with the dripping method, enable the preservation even thermolabile compounds, such as drugs, organisms, proteins, and fragrances, since mild conditions are used. However, large beads are produced, which can limit their application. A rarely used and cost‐effective option for size reduction is the jet cutter, a cutting tool that, during its rotation, breaks the jet in smaller sizes, producing very small beads. The results of this study showed that the use of jet cutter was effective in the reduction of bead size and developed some basis for broadening its application for encapsulation using different materials.

Palm oil is a carotenoid‐rich natural compound, whose microencapsulation by complex coacervation may protect it against adverse conditions, allowing applications in food formulations for nutritional enrichment and natural pigmentation. Besides, since the coacervates are insoluble in acid pH of stomach, this undigested lipid is delivered slowly in the intestinal tract, which can help treatment of metabolic disturbs. Accordingly, this study intended to optimize palm oil microencapsulation by complex coacervation using gelatin and gum Arabic as wall materials. For this purpose, the effects of wall material concentration (WM) (2.5, 5.0, and 7.5% w/v), gelatin:gum Arabic ratio (G:GA) (1:2; 1:1; 2:1), and core:wall material ratio (C:WM) (75, 100, and 125%) on the encapsulation efficiency, particle morphology, and size distribution of microcapsules were investigated. Microencapsulation assays followed a factorial central design and, after coacervation, the microcapsules were freeze‐dried. The highest values of encapsulation efficiency were obtained using G:GA = 1:1 or 2:1 with C:WM = 100%, whereas the WM concentration could vary from 2.5 to 7.5%. High concentrations of WM (7.5%) and G:GA = 2:1 hampered the formation of spherical or oval microcapsules. Microcapsules showed average diameter (D[4.3]) between 97 and 690 µm, with increasing concentration of WM and higher C:WM ratio contributing to formation of larger microcapsules. The G:GA ratio showed the highest influence on the particle size, with the 1:2 ratio resulting in smaller microcapsules. Practical applications Palm oil is a significant source of antioxidants and other phytonutrients, and its microencapsulation may protect these bioactive compounds, enabling its use to nutritional enrichment of dry food formulations, at the same time as functioning as a natural pigment given the intense reddish‐orange color of the oil. In addition, the microcapsules may slow down palm oil release in the gastrointestinal tract, since the coacervates are insoluble in acid pH of stomach, allowing this nutrient to achieve the ileum before being digested and help treatment of metabolic disturbs. Accordingly, microencapsulation of palm oil can be of great interest for food and pharmaceutical industries to develop controlled‐delivery systems to encapsulate and slow down digestion of lipids, inducing modulation of satiety response.

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Food safety and extended shelf life linked to convenience were the major reasons for the development of the packaging field. However, advances in material science and the widespread encapsulation technologies are allowing the establishment of new concepts for packages, such as intelligent and active packages. Particulate systems have been developed in recent years for the most diverse area with several purposes that can be employed to improve packaging performance mainly focusing on the modification of barrier properties. This review analyzes the recent developments using encapsulation in food packaging and the main concepts about mass transfer evolved in the functionality of these packages, as well as discusses the research challenges faced by the food packaging sector.

Solid lipids are commonly used as carrier systems for encapsulation processes. However, formulations containing only solid lipids tend to form a highly ordered crystal lattice, which can expel the active compound during long-term storage, due to the dynamics of polymorphic transitions. Regarding the aspects of particle production, the cooling step of the melted lipid is essential for determining the type of formed crystals. This work aimed to analyze the effects of the crystallization step on the physicochemical properties of lipid particles. Carnauba wax (CW) particles with a relatively high melting point (T m = 78 C) were produced by the dripping method, based on melting-crystallization steps, and by cold extrusion, which uses temperatures lower than the melting point of the lipid. Then, the physical properties, thermal behavior, and X-ray of CW particles were analyzed. The particles obtained by dripping and extrusion presented mean sizes of 3.7 and 1.5 mm, respectively. All particles presented a similar thermal behavior (T m = 78 C; ΔH = 200 J g −1 ) and crystalline arrangement of the lipids. However, the dripping system presented an operational problem of clogging, requiring efficient thermal insulation, whereas the extrusion is a cost-effective, time-saving, and eco-friendly method.

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