Background Many biologically active and functional components are chemically unstable, and exhibit variable water/oil solubility, which reduce their bioavailability and efficacy. Therefore, the development and application of edible emulsion-based delivery systems for these compounds using food-grade materials would be extremely beneficial to the food industry. Recently, particle-stabilized emulsions (i.e., Pickering emulsions) have attracted significant attention from the scientific community owing to their surfactant-free character. Scope and approach This Review summarizes the recent applications of Pickering emulsions stabilized by food-grade particles for the encapsulation and delivery of lipophilic and hydrophilic bioactives. Firstly, the beneficial features of Pickering emulsions and their potential use for targeted delivery of bioactives are discussed. Next, different designs of Pickering emulsion-based delivery system (PEDS) and their performance in bioactives delivery are highlighted. Finally, the challenges and opportunities for future research are addressed. Key findings and conclusions Particles derived from proteins, polysaccharides, and lipids have received considerable research interest owing to their intrinsic biochemical properties that enable the development of PEDS that can improve the stability and delivery of bioactives. Different types of PEDS (i.e., O/W or W/O single emulsions, O/W/O or W/O/W double emulsions, emulgel, high internal phase emulsion, and microcapsules) have been developed and studied as versatile tools for encapsulation of both lipophilic and hydrophilic bioactives. Future research should focus on the elucidation of the release mechanism of bioactives from PEDS and the evaluation of the compatibility of PEDS with real food systems, as well as the efficacy and safety of PEDS using in vivo model. Development of PEDS in non-liquid state should also be a focus for future research in order to bridge the gap between lab and market.

Food-grade Pickering emulsions for encapsulation and delivery of bioactives

Background The essential fatty acids (EFAs) are recognized as functional oils for humans as they possess nutritional and pharmaceutical benefits and can promote whole-body health in different ways. Scope and approach This review describes and classifies different types of EFAs, gives an overview of the spray drying process alongside its probable challenges for encapsulation of functional oils. Also, various used wall materials, and the effects of the process conditions on the encapsulation efficiency of functional oils have been discussed. Moreover, it focuses on the spray drying encapsulation of functional oils derived from marine and plant-based sources in recent years (2016-2019), and the fortification of different foods with encapsulated functional oils. Key findings and conclusions Protecting EFAs through efficient methods such as spray drying encapsulation and enriching the various foods with encapsulated functional oils is an emerging field, which has drawn lots of attention these days. The wall materials (carriers) and spray drying conditions are two major influential factors that can easily affect the properties of final produced powders.

Recent advances in the spray drying encapsulation of essential fatty acids and functional oils

Background Continuous increase in global human population and depletion of natural resources threat to environment needs and sustainable food supply. In particular, food industries generate an extensive amount of by-products. Several studies have shown that food by-products might be suitable feedstock to recover bioactive compounds such as phenolics, carotenoids, proteins, likewise their promising technological properties. Thus, this paper aims to overview recent advances in the utilization of food by-products. Scope and approach This review deals with the main techniques for obtainment, enrichment, incorporation, and technological application of food by-products. Finally, several examples are discussed considering the application of food by-products as a bioactive source to enrich food, through encapsulation or another technological process, or as an encapsulating material. This study's main approach is to critically discuss the techno-functionality of food by-products, highlighting their potential for application in food science and technology. Key findings and conclusions There are many nutritional properties of food by-products; however, their technological properties are promising. For example, orange juice by-products can be used as encapsulating material by spray drying. The apple pomace can stabilize Pickering-type emulsions and has prebiotic potential. Saccharomyces cerevisiae can be used as an encapsulating agent to hydrophobic and hydrophilic compounds, while its extract can improve the sensory characteristics of cooked ham. Thus, by-products valorization is a challenging field of study since the circular economy concepts introduced in food science aim to ensure environmental protection and enhance economic development, reducing the environmental impact of food production.

The use of food by-products as a novel for functional foods: Their use as ingredients and for the encapsulation process

Spray-dried alginate-coated Pickering emulsion stabilized by chitosan for improved oxidative stability and in vitro release profile

Background Pomegranate is a prevalent fruit with a vast arena of food and pharmaceutical applications. The oil obtained from pomegranate seeds is known for its functional and beneficial health properties. Recently, there was an escalation in the studies concentrating on the applications of PSO in food and the related consequences. Scope and approach This review provides an overview of different methods studied for the extraction of PSO along with its astounding fatty acid profile. The approach also demonstrates the multifaceted applications of PSO in the food industry, ranging from an animal feed to food packaging. An abridged view of the stability, toxicity, and authentication of PSO is given along with an update on the potential market. Scrutiny on scientific literature identified many reviews on pomegranate, its derivatives, and fruit seed oils; however, the present study specifically focused on the recent progress in PSO works. Key findings and conclusions The PSO can be applied as a functional component in food and beverages, a fat replacer, and a property enhancer in food packaging. Moreover, enriching the lipid profile of meat and dairy products ensures the supply of conjugated fatty acids in the daily diet without changing the prevailing diet patterns. The assessment reveals an overview of the PSO applications in food from extraction to daily dietary intake and its immense potentialities, being the major source of punicic acid.

Pomegranate seed oil in food industry: Extraction, characterization, and applications

Pomegranate seed oil (PSO) is rich in bioactive compounds and is susceptible to oxidation. This research sought to encapsulate PSO in conventional and Pickering emulsions using whey protein isolate (WPI) microgels, WPI in its natural form, gum Arabic (GA), and WPI combinations with GA, maltodextrin (MD), and modified starch (Capsul®) as aqueous phase/emulsifier followed by spray drying. Emulsions with 1.39–2.55 μm droplet size, low viscosity (1.47–3.96 mPa s), and final interfacial tensions of 4.21–9.97 mN m−1 were obtained. All formulations were stable with the Turbiscan stability index between 4.57% and 12.95% at 24 h. Emulsions resulted in particles with encapsulation efficiency and yield of 56.28–73.83% and 28.07–93.99%, respectively. PSO powders had small particle sizes (9.86–22.60 μm), high glass transition temperature (103.24–121.62 °C), and oxidative stability index (OSI) of 2.71 h and in the range of 4.11–21.23 h for non-encapsulated and encapsulated PSO, respectively. All formulations promoted the oil oxidative protection when compared with the non-encapsulated one. Treatments presented feasible values of Aw, moisture, solubility, and hygroscopicity for handling and storage of the powders. WPI, WPI:Capsul®, and Pickering treatments promoted greater protection of the encapsulated oil; however, the combination of WPI with modified starch was considered the best wall material, allowing protection of PSO and future applications in the food industry.

Encapsulation of Pomegranate Seed Oil by Emulsification Followed by Spray Drying: Evaluation of Different Biopolymers and Their Effect on Particle Properties

The influence of gum arabic, modified starches (EMCAP® and SNOW-FLAKE® [SN]) and their combination (1:1) as wall materials in microencapsulation of paprika oleoresin (PO) by emulsification followed...

Effect of modified starches and gum arabic on the stability of carotenoids in paprika oleoresin microparticles

This work aimed to obtain novel materials from malt modification for using in oil/water emulsions. Malt was modified using stearic acid (2% w/w) in combination with different energy densities (33.8 × 106, 60 × 106, 72.5 × 106, and 107.5 × 106 J/m3) from ultrasound probe resulting in four materials. These materials were characterized by degree of substitution (DS), amylose content, dextrose equivalent (DE), protein content, solubility, thermal properties, Fourier-transform infrared spectroscopy (FT-IR), crystallinity analysis by X-ray diffraction, and scanning electron microscopy. Emulsions containing 15% total solids (25% canola oil and 75% modified malt as stabilizing agent) were prepared and characterized. Results showed that increasing energy densities produced different effects on malt properties due to an increase in DS, amylose content, and DE values. The sonication process in combination with stearic acid increased malt solubility and the gelatinization temperature of malt, caused modifications of starch crystallinity in the amorphous region and hydrolysis of starch granules, and promoted good stabilizing properties for emulsions containing modified malt.

Eveling Oliveira Bezerra

Papers

Encapsulation of Pomegranate Seed Oil by Emulsification Followed by Spray Drying: Evaluation of Different Biopolymers and Their Effect on Particle Properties

Effect of modified starches and gum arabic on the stability of carotenoids in paprika oleoresin microparticles

Barley malt esterification after ultrasound and stearic acid treatment: characterization and use as stabilizing agent in oil-in-water emulsions

Physicochemical Properties of Capsicum Oleoresin Emulsions Stabilized by Gum Arabic, OSA-Modified Corn Starch, and Modified Malt