Effect of different dextrose equivalents of maltodextrin on oxidation stability in encapsulated fish oil by spray drying

Microencapsulated Asiatic Pennywort (Centella asiatica) fortified chocolate oat milk beverage: Formulation, polyphenols content, and consumer acceptability

This study investigated the use of microencapsulated Asiatic pennywort (Centella asiatica) (CA) as a functional ingredient to formulate a novel chocolate oat milk beverage. The main objectives of the study were to characterize and encapsulate bioactive components from CA and to determine the polyphenol content and sensory properties of the beverage. CA extract was microencapsulated using maltodextrin and gum Arabic as carriers and subsequently freeze-dried to produce microcapsules. Microencapsulated CA was incorporated into chocolate oat milk at varying concentrations. Polyphenol content of the beverages was quantified using liquid chromatography-mass spectrometry. Consumer acceptability and sensory perception of the beverages were evaluated through an acceptance test and a check-all-that-apply test, respectively, to assess the sensory characteristics of the chocolate oat milk beverage. CA fortified chocolate oat milk contained fourteen polyphenols. Increasing the concentration of microencapsulated CA led to an increase in the polyphenol content of the beverage. Among the identified polyphenols, asiatic acid and asiaticoside stood out as the unique and most abundant compounds in CA (p < 0.05). Additionally, the incorporation of cocoa powder into the beverage further contributed to the polyphenol content, introducing bioactive compounds such as benzoic acid, caffeic acid, catechin, chlorogenic acid, kaempferol, luteolin, madecassic acid, p-coumaric acid, and quercetin. Evaluation of consumer acceptability revealed that chocolate oat milk beverages containing 2% and 4% microencapsulated CA were liked by consumers. However, beverages with higher concentrations of CA were perceived as less acceptable, characterized by grassy, bitter, and earthy attributes. In conclusion, this study demonstrates the potential of microencapsulated CA as a functional ingredient in chocolate oat milk beverages. PRACTICAL APPLICATION: This study reveals new insights on the microencapsulation of bioactive compounds in CA, proposing its potential as a novel functional ingredient in food and beverage applications in Western markets. The study revealed microencapsulated CA retained polyphenols in CA including asiatic acid and asiaticoside responsible for its bioactive properties. Consumer perception of CA added to oat milk revealed that it can be added at an acceptable level of 4%; however, higher amounts can decrease consumer acceptability. As practitioners explore the incorporation of CA as a functional component in food products, it is crucial to explore preservation techniques for the sensitive bioactive components while balancing the optimal amount of CA to enhance overall consumer liking.

Exploring conventional and emerging dehydration technologies for slurry/liquid food matrices and their impact on porosity of powders: A comprehensive review

The contribution of dehydration to the growing market of food powders from slurry/liquid matrices is inevitable. To overcome the challenges posed by conventional drying technologies, several innovative approaches have emerged. However, industrial implementation is limited due to insufficient information on the best-suited drying technologies for targeted products. Therefore, this review aimed to compare various conventional and emerging dehydration technologies (such as active freeze, supercritical, agitated thin-film, and vortex chamber drying) based on their fundamental principles, potential applications, and limitations. Additionally, this article reviewed the effects of drying technologies on porosity, which greatly influence the solubility, rehydration, and stability of powder. The comparison between different drying technologies enables informed decision-making in selecting the appropriate one. It was found that active freeze drying is effective in producing free-flowing powders, unlike conventional freeze drying. Vortex chamber drying could be considered a viable alternative to spray drying, requiring a compact chamber than the large tower needed for spray drying. Freeze-dried, spray freeze-dried, and foam mat-dried powders exhibit higher porosity than spray-dried ones, whereas supercritical drying produces nano-porous interconnected powders. Notably, several factors like glass transition temperature, drying technologies, particle aggregation, agglomeration, and sintering impact powder porosity. However, some binders, such as maltodextrin, sucrose, and lactose, could be applied in controlled agglomeration to enhance powder porosity. Further investigation on the effect of emerging technologies on powder properties and their commercial feasibility is required to discover their potential in liquid drying. Moreover, utilizing clean-label drying ingredients like dietary fibers, derived from agricultural waste, presents promising opportunities.

Encapsulation efficiency and fatty acid analysis of chia seed oil microencapsulated by freeze-drying using combinations of wall material

Chia seed oil (CSO) was encapsulated using whey protein concentrate (WPC) and modified tapioca starch (MTS) through freeze-drying. A central composite design was used to evaluate the effect of independent variables (MTS:WPC ratio, homogenization pressure, and oil content). Encapsulation efficiency (EE) and α-linolenic acid content (ALA) were evaluated for all runs. The results showed that higher MTS ratios led to maximum ALA retention, while higher WPC ratios led to maximum EE. The optimized conditions resulted in high EE (97 %), ALA content (59.54 %), and a Ω-3:Ω-6 ratio (3.34). The fatty acid composition, oxidative and thermal stability showed that the MTS:WPC ratio of 25:75 was the best combination for encapsulating CSO. The encapsulated CSO with a balanced Ω-3:Ω-6 ratio can be used as a functional ingredient in foods for health benefits.

Research progress of starch as microencapsulated wall material

Starch is non-toxic, low cost, and possesses good biocompatibility and biodegradability. As a natural polymer material, starch is an ideal choice for microcapsule wall materials. Starch-based microcapsules have a wide range of applications and application prospects in fields such as food, pharmaceuticals, cosmetics, and others. This paper firstly reviews the commonly used wall materials and preparation methods of starch-based microcapsules. Then the effect of starch wall materials on microcapsule properties is introduced in detail. It is expected to provide researchers with design inspiration and ideas for the development of starch-based microcapsules. Next the applications of starch-based microcapsules in various fields are presented. Finally, the future trends of starch-based microcapsules are discussed. Molecular simulation, green chemistry, and solutions to the main problems faced by resistant starch microcapsules may be the future research trends of starch-based microcapsules.

Strategies for improving loading of emulsion-based functional oil powder

Functional oil is type of oil that is beneficial to human health and has nutritional value, however, functional oils are rich in bioactive substances such as polyunsaturated fatty acids which are sensitive to environmental factors and are susceptible to oxidation or decomposition. Construction of emulsion-based oil powder is a promising approach for improving the stability and solubility of functional oils. However, the low effective loading of oil in powder is the main challenge limiting encapsulation technology. This manuscript focuses on reviewing the current research progress of emulsion-based functional oil powder construction and systematically summarizes the processing characteristics of emulsion-based oil powder with high payload and summarizing the strategies to enhance the payload of powder in term of emulsification and drying, respectively. The impact of emulsion formation on oil powder production is discussed from different characteristics of emulsions, including emulsion composition, emulsification methods and emulsion types. In addition, the current status of improving material loading performance by various modifications to the drying technology is discussed, including the addition of drying processing additives, changes in drying parameters and the effect of innovative technological means.

Wall Materials for Encapsulating Bioactive Compounds via Spray-Drying: A Review

Spray-drying is a continuous encapsulation method that effectively preserves, stabilizes, and retards the degradation of bioactive compounds by encapsulating them within a wall material. The resulting capsules exhibit diverse characteristics influenced by factors such as operating conditions (e.g., air temperature and feed rate) and the interactions between the bioactive compounds and the wall material. This review aims to compile recent research (within the past 5 years) on spray-drying for bioactive compound encapsulation, emphasizing the significance of wall materials in spray-drying and their impact on encapsulation yield, efficiency, and capsule morphology.

Effects of particle formation behavior on the properties of fish oil microcapsules fabricated using a micro-fluidic jet spray dryer

Fish oil was encapsulated with whey protein isolate (WPI) as wall material using a Micro-Fluidic Jet Spray Dryer. The effects of core/wall material ratio, drying temperature and total solids content on the properties of microcapsules were studied. Low core/wall material ratios at 1:5 and 1:3 resulted in high encapsulation efficiency (EE) and excellent oxidative stability of microparticles during storage. Reducing the inlet temperature from 160 to 110 °C remarkably decreased EE from around 99 to 64.8%, associated with substantial increases in peroxide value during storage. The total solids content mainly altered the morphology of microcapsules, showing little influence on EE and oxidative stability. We proposed that the different drying conditions impacted on particle formation behavior during spray drying, which could be a crucial factor responsible for the differences in the quality attributes of microparticles. A low core/wall material ratio and high drying temperature facilitated the formation of a rigid protein skin at droplet surface during drying, whereas a high solids fraction in the droplets could limit possible droplet shrinkage. These factors contributed positively to the encapsulation of the lipophilic core material.

Effect of Dextrose Equivalent on Maltodextrin/Whey Protein Spray-Dried Powder Microcapsules and Dynamic Release of Loaded Flavor during Storage and Powder Rehydration

The preparation of powdered microcapsules of flavor substances should not only protect these substances from volatilization during storage but also improve their diffusion during use. This study aimed to investigate the effects of maltodextrin (MD) with different dextrose equivalent (DE) values on retention of flavor substances during storage, and the dynamic release of flavor substances during dissolution. MDs with three different DE values and whey protein isolate were mixed in a ratio of 4:1 as wall materials to encapsulate ethyl acetate, and powdered microcapsules were prepared by spray drying. It was proved that MD could reduce the diffusion of flavor substances under different relative humidity conditions through the interaction between core material and wall material. During dissolution, MD released flavor substances quickly owing to its superior solubility. The reconstituted emulsion formed after the powder dissolved in water recaptured flavor substances and made the system reach equilibrium. This study explored the mechanism of flavor release during the storage and dissolution of powder microcapsules and should help us understand the application of powder microcapsules in food systems.

A systematic review and meta-analysis of fish oil encapsulation within different micro/nanocarriers

Fish oil is one of the most important sources of omega 3 polyunsaturated fatty acids (PUFAs), especially eicosapentaenoic acid and docosahexaenoic acid which are the most important PUFAs with several health benefits. However, PUFAs are prone to oxidation and have a poor water solubility which limits the use of fish oils into food formulations. Encapsulation techniques can be applied to overcome these challenges. There is a large number of published micro/nanoencapsulation papers, where each of them contains a limited number of wall materials, feed formulation, encapsulation technique, and storage conditions. Therefore, without systematic evaluation of the data extracted from available studies, the design of functional foods containing fish oil would not be very successful. The objective of this systematic review is a meta-analysis of published researches on the nano/microencapsulation of fish oil. A comprehensive literature search was performed between 1 October and 31 December 2019 with encapsulation, fish oil, and oxidative stability keywords. Overall, 39 qualified articles were selected for the statistical analysis. Based on the technique used for encapsulation, the fish oil-loaded carriers were classified into four main groups: (a) spray-dried particles; (b) freeze-dried particles; (c) electrospun fibers and electrosprayed capsules; and (d) other carriers prepared by supercritical antisolvent, gelation, liposomes, spray-freeze drying, and transglutaminase catalyzed cross-linking. The three most frequent methods applied for fish oil encapsulation were spray drying (42.86%), freeze drying (21.43%), and electrohydrodynamic (19.04%) methods, respectively. Averagely, the best encapsulation efficiency was obtained for electrohydrodynamic processes. Also, the combination of polysaccharide-protein based wall materials provided the best performance in terms of fish oil encapsulation efficiency.

Factors determining the surface oil concentration of encapsulated lipid particles: impact of the emulsion oil droplet size

Microencapsulation of oxidation sensitive oils aims to separate lipids from the environmental oxygen by embedding oil droplets in a solid matrix, which builds a physical barrier. Some oil droplets are not fully incorporated and are in contact with the powder surface generating surface oil. It is proposed that the probability of oil droplets being in contact with the particle surface increases with the oil droplet size. The aim of the study is to investigate the impact of the oil droplet size on the encapsulation efficiency (EE). Two sets of feed emulsions differing in the applied homogenization pressure and in the protein to oil ratio were spray dried using a pilot plant spray dryer. The oil droplet size of the emulsion was determined by static light scattering (SLS). In addition, nuclear magnetic resonance (NMR) was used to measure the d3,2 of oil droplets in the emulsion and in the powder before and after surface oil removal. Encapsulates were analyzed regarding aw, moisture content, particle size, oil load and EE. The oil droplet size in the emulsion decreased with increasing protein to oil ratio as well as with the homogenization pressure. Large oil droplets and in particular droplet clusters resulted in more non-encapsulated oil. The experimentally determined EE was in accordance with the theoretical one, calculated based on the droplet and particle diameter. For emulsions with a diameter > 1 µm, the d3,2 decreased in the powder and further by removing the surface oil, which was related to the deformation of oil droplets contributing to the non-encapsulated oil.

Stability and release behavior of encapsulated flavor from spray-dried Saccharomyces cerevisiae and maltodextrin powder

Yeast cells (Saccharomyces cerevisiae), from which β-glucans have been partially extracted, were used to encapsulate flavor inside the lipid bilayer membrane as natural encapsulant. The focus of this study was to investigate the release and stability of flavors (d-limonene and ethyl hexanoate) encapsulated in yeast cells and maltodextrin (MD) (DE = 19) by spray drying. The release behavior of encapsulated flavors from yeast cells was measured at 40, 60, 80, and 105 °C with different moisture content (0, 50, 100, and 200% of powder). Water affected flavor release from the yeast cells. The release rate constants were correlated using Gaussian distribution of the activation energy of the release rate constants. The release of d-limonene from the spray-dried MD powder showed a different trend than that of yeast cells at various temperatures. The activation energies of the release rate constant for ethyl hexanoate and d-limonene from yeast were 55 and 49 kJ/mol, respectively, under a wet condition. The formation rates of limonene oxide and carvone were slower in yeast than that of MD powder at 30 °C after 2 months.