The porosity of carbohydrate-based spray-dried microparticles containing limonene stabilized by pea protein: Correlation between porosity and oxidative stability.

In this study, the effects of different concentrations of pea protein concentrate (PPC) in the physical properties, porosity features, and oxidative stability of maltodextrin-based spray-dried microparticles containing orange essential oil (OEO, rich in limonene) were evaluated. The use of PPC resulted in spray-dried microparticles with encapsulation efficiencies of about 99 wt%, without visible pores, and relatively high glass transition temperature (66,4 °C) at Aw âˆ¼ 0.3. The nitrogen adsorption and positron annihilation lifetime spectroscopy measurements showed that the increase of PPC concentration from 2.4 to 4.8 wt% (g of PPC/100 g of emulsion) did not affect the porosity features of the microparticles. These results were confirmed by the profiles of OEO retention and limonene oxide production, which were similar for both samples throughout four weeks of storage. Based on these results, we verified that the lower amount of PPC we tested can effectively protect the OEO during storage, showing that a relatively cheaper orange flavor powder can be produced using less protein.

Prospection of the use of encapsulation in food packaging.

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.

Performance of oil-in-water emulsions stabilized by different types of surface-active components.

The emulsion stability depends on the physicochemical properties of the dispersed phase and their interaction with the continuous phase. Surface-active compounds (SAC) are added in emulsions to reduce the interfacial tension (IT) between these phases and keep the oil droplets stabilized. Moreover, small amounts of SAC can occupy intermolecular voids in the dried matrix, reducing the oxidation. However, the formulation must reflect a trade-off between protection and emulsion stabilization. Therefore, this work aimed to identify the minimum concentration of SAC (modified starch-MS, gelatin-GE, and whey protein isolate-WPI) ranging from 0.48 to 6 % (w/w) to form and stabilize droplets of an unsaturated triglyceride (fish oil-FO) or a volatile oil (orange essential oil-OEO). GE did not change the IT (6.7 mN/m) and stabilized the emulsions only through an increase of the viscosity (∼42 mPas for FO-emulsions and ∼97 mPas for OEO-emulsions), presenting high droplet size (∼10 µm) and low surface charge (∼1.5 mV). WPI reduced the IT to a limit value (4.5 mN/m at 1.2 % w/w for OEO and 5.3 mN/m at 2.4 % w/w for FO), whereas MS reduce constantly the IT with the increase of the concentration for both oils (∼4.2 mN/m at 6 % w/w). Both WPI and MS-emulsions presented similar droplet size (∼2.0 µm), but WPI presented higher surface charge of WPI-emulsions (-45 mV) than MS-emulsions (-30 mV). This study allowed to gain a consistent understanding of structure-property relationships on the use of SAC in emulsions.