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In the present study, dryings by foam mat, foam mat freeze-drying, spray-drying and freeze-drying were proposed to microencapsulate bioactive compounds extracted from espresso spent coffee. Albumin, maltodextrin and gum arabic were used as wall materials, and the dried product was characterized and compared. The foams produced were dried in a tunnel dryer at different temperatures and air velocities. The drying time ranged from 200 to 450 min, and shorter drying times were obtained for the highest temperatures. For all drying methods, dried products with good physicochemical properties and high levels of phenolic and antioxidant compounds were obtained. The foam mat resulted in samples with higher moisture content and bulk density. On the other hand, freeze-dried samples had greater hygroscopicity and shorter wettability times. Spray-dried samples were lighter (highest value of parameter L*). The encapsulation efficiency values were between 66.46% and 88.01%, with the lowest values obtained for the foam mat. [ABSTRACT FROM AUTHOR]

Propolis, which is a bee glue is potentially a useful food additive since it contains antioxidant and preservative-like properties. However, its application in the food industry remains limited, due to its strong taste and low solubility. Microencapsulation is a technique that can improve its characteristics and the most widely used is spray drying. To obtain a spray-dried product with desired properties, optimization of both the encapsulating materials and equipment operating conditions are crucial. In this review, the use of different wall materials and operational conditions for spray drying of propolis are discussed, in order to guide selection of these parameters to obtain optimal spray dried microcapsules. In addition, comparison with other microencapsulation techniques is also discussed and pertinent industrial applications of spray-dried propolis given. [ABSTRACT FROM AUTHOR]

Repaglinide (RPG, antidiabetic) and Diltiazem HCL (DIL, antihypertensive) loaded ethyl cellulose (EC) nanoparticles were prepared by the spray drying process using Placket Burman Design (PBD). The amount of EC (A, mg), Methanol (B, ml), Inlet temperature (C, OC), Feed rate (D, rpm), Nozzle diameter (E, mm) and Aspiration (F, rpm) were considered independent variables while EE of RPG (Y1) and EE of DIL (Y2) were selected as dependent variables. The optimized DIL and RPG loaded EC nanoparticles were further used for the development of oral fast disintegrating sustained release tablets by direct compression method. The tablets were evaluated for weight variation, thickness, hardness, disintegration time, friability and dissolution test. FTIR study showed no chemical interaction between drug and polymer. Scanning electron microscope showed spherical as well as oval shape and discrete nature of both nanoparticles. The physical parameters of oral fast disintegrating tablets developed with optimized formulation of drug loaded nanoparticles were found within the range. Drug loaded nanoparticles as well as oral fast disintegrating tablets showed very good sustained release behavior. [ABSTRACT FROM AUTHOR]

Cocona is native to Amazon, rich in 5-caffeoylquinic acid (5-CQA). The objective of this study was to evaluate the influence of the inlet air temperature (120-180 °C) and of the combination of encapsulating agents maltodextrin and hydrolyzed collagen (MD:HC, 0:100-100:0), on cocona powders, by central composite rotatable design (CCRD). The main results were: solids recovery of 30.9-68.2%, antioxidant capacities of 98.6-141.3 mM TE/g (FRAP) and 53.1-143.3 mM TE/g (ABTS), 5-CQA of 99.7-670.8 µg/g and encapsulation efficiency of 91.2-98.1%. The best parameters, by CCRD were an MD:HC of 20:80 and a temperature of 120 °C, with high values of FRAP (88.12 mM TE/g), ABTS (81.39 mM TE/g), 5-CQA (532.20 µg/g), and encapsulation efficiency (95.97%). Additionally, cocona powder was evaluated for hygroscopicity (17.14 g/100 g), solubility (76.51%), morphology and color. It is, therefore, a good alternative to enhancing foods, given the bioactive properties of the fruit and of HC. [ABSTRACT FROM AUTHOR]

Spray drying is one of the oldest, most common, and economical techniques typically employed for producing dry powders from flowable feeds which can be a solution, dispersion, or even paste. In the food industry, spray drying technology has also been employed as a means for microencapsulation of food active ingredients such as oils, fragrances, and flavors. Spray drying as a microencapsulation technique provides several beneficial functionalities such as easing handling of liquid labile active compounds, enhancing solubility, improving stability, providing protection against degradation, controlling or delaying release, and masking unpalatable tastes or smells. This article reviews the latest findings and research works on microencapsulation of food core materials by spray drying. It is aimed to give an overview of the vast variety of food active compounds studied in this particular area of interest. This article is organized by the type of food core material, i.e., oil, flavors, antioxidants and polyphenols, nutrients, pigments, vitamins, and enzymes, to facilitate comprehensive discussion on physicochemically similar compounds. [ABSTRACT FROM AUTHOR]

The impact of spray drying conditions on encapsulated rapeseed oil was investigated regarding the encapsulation efficiency (EE). The drying rate was modified by the solid content (25–55% w/w) of atomized feed droplets, the inlet temperature (140–220 °C) and relative humidity (0.12–1.57%) of the drying air. The moisture, aw, bulk and tapped density, particle size, and EE were analyzed. An accelerated drying rate due to a higher solid content and inlet temperature as well as a slower drying induced by an increased air humidity resulted in larger particle and more efficient encapsulation. A higher EE was obtained with increasing particle size which is in accordance with a theoretical EE calculated based on the particle- and oil droplet diameter. [ABSTRACT FROM AUTHOR]

In the present study, taste masked drug–resin complex (DRC) of efavirenz (EFV) was prepared by spray drying technique. The DRC was then incorporated in to a fast dissolving tablet dosage form. EFV is antiretroviral agent of very bitter taste and low oral bioavailability. To investigate the influence of the independent variables on encapsulation efficiency (EE) as well as on the bitter taste of EFV, response surface methodology was employed. Ion-exchange resin (tulsion-335) and amount of solvent were selected as the independent variables while the EE was selected as the dependent variable. DRC was characterized for EE, X-ray diffraction, particle size distribution, Fourier transform infrared spectroscopy, surface morphology, and in vitro dissolution study. The spectrophotometric method was used for the evaluation of bitter taste of EFV. The EE was found to be 37–84%. The compressed tablets were evaluated for the hardness, Friability, wetting time, disintegration time and in vitro drug release studies. This study confirmed that complexation of the drug with an ion-exchange resin can effectively mask the bitter taste of the drug in combination with production of fast dissolving tablets. [ABSTRACT FROM AUTHOR]

This study was performed to investigate the influence of air inlet temperature (AIT) on the microencapsulation of hazelnut oil by spray drying. Encapsulated powders were analyzed for moisture content, powder yield, surface oil, encapsulation efficiency (EE), bulk density, and particle morphology. The obtained results demonstrated that moisture content, surface oil, and bulk density decreased by 37.8, 27.5, and 33%, respectively as AIT increased from 140 to 220°C. However, powder yield and encapsulation efficiency increased considerably with the rise in AIT. Higher EEs of about 75–80% were observed in this study. [ABSTRACT FROM PUBLISHER]

Ethyl cellulose (EC) and Eudragit RL-100 (ERL-100) were used for the preparation of sustained released microparticles of mefenamic acid (MFN) by using oil-in-oil (o/o) solvent evaporation as well as spray drying. A Plackett-Burman design was employed using Design-Expert software. The resultant microparticles were characterized for their size, surface morphology, encapsulation efficiency, and drug release. Imaging of microparticles was performed by field emission scanning electron microscopy. The drug and polymer interaction was investigated by Fourier transform infrared (FTIR) spectroscopy and X-ray powder diffractometry (XRPD). The microparticles showed encapsulation efficiency in the range of 29.44 to 89.20% by solvent evaporation and 83.73 to 96.69% by spray drying. The surface of the microparticles was smooth, round, and regular, without any erosion and cracking. The size of the microparticles was found to be in the range of 6.55 to 41.1 µm. FTIR analysis confirmed no interaction of MFN with the polymers. XRPD showed the dispersion of the drug within the microparticle formulation. These results helped in finding the optimum formulation variables for encapsulation efficiency (EE) of microparticles. [ABSTRACT FROM PUBLISHER]

This study evaluated the influence of wall material concentration (10–30%), inlet temperature (135–195°C), and feed rate (0.5–1.0 L · h−1) on the properties of rosemary oil microencapsulated by spray-drying, with gum arabic as carrier. Powder recovery, surface oil, oil retention, and hygroscopicity varied from 17.25%–33.96%, 0.03%–0.15%, 7.15%–47.57%, and 15.87%–18.90%, respectively. The optimized conditions were determined to be a wall material concentration of 19.3%, an inlet air temperature of 171°C, and a feed flow rate of 0.92 L · h−1. At this condition, particles presented no fissures and the compositions of pure and microencapsulated oil were similar. The sorption isotherms could be described by the GAB model. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the effect of the type of wall material and the oil load on the microencapsulation of flaxseed oil by spray drying. Gum arabic, whey protein concentrate, and a modified starch were used to produce the microcapsules, each with four oil concentrations (10, 20, 30, and 40% oil, w/w, with respect to total solids), for a total of 12 tests. Initially, the feed emulsions were characterized for stability, viscosity, and droplet size. Then they were dried in a laboratory-scale spray dryer and the resulting particles were analyzed for encapsulation efficiency, lipid oxidation, moisture content, and bulk density. The increase in oil concentration led to the production of emulsions with larger droplets and lower viscosity, which directly affected powder properties, resulting in lower encapsulation efficiency and higher lipid oxidation. Among the three wall materials evaluated, the modified starch showed the best performance, with the highest encapsulation efficiency and lowest peroxide values. [ABSTRACT FROM AUTHOR]

A new technique for lycopene microencapsulation by spray drying using dehumidified air as the drying medium was developed and the optimum operating conditions for encapsulation efficiency were determined. A pilot-scale spray dryer was employed for the spray-drying process. The modification made to the original design consisted of connecting the dryer inlet air intake to an absorption air dryer. The dextrose equivalent (DE) of maltodextrin, ratio of core to wall material, feed temperature, inlet air temperature, drying air flow rate, and compressed air flow rate were the factors investigated with respect to encapsulation efficiency. The resulting microcapsules were evaluated in terms of moisture content, bulk density, rehydration ability, lycopene isomerization, and storage stability. The optimum operating conditions were found to be as follows: ratio of core to wall material, 1:3.3; feed temperature, 52°C; inlet air temperature, 147°C. Under these conditions, the maximum encapsulation efficiency was about 93%. The use of dehumidified air was proven to be an effective way of increasing lycopene encapsulation efficiency. [ABSTRACT FROM AUTHOR]

Microencapsulation is a rapidly expanding technology which is a unique way to package materials in the form of micro- and nano-particles, and has been well developed and accepted within the pharmaceutical, chemical, food and many other industries. Spray drying is the most commonly used encapsulation technique for food products. A successful spray drying encapsulation relies on achieving high retention of the core materials especially volatiles and minimum amounts of the surface oil on the powder particles for both volatiles and non-volatiles during the process and storage. The properties of wall and core materials and the prepared emulsion along with the drying process conditions will influence the efficiency and retention of core compounds. This review highlights the new developments in spray drying microencapsulation of food oils and flavours with an emphasis on the encapsulation efficiency during the process and different factors which can affect the efficiency of spray drying encapsulation. [ABSTRACT FROM AUTHOR]

Submicron emulsion particles of d-limonene prepared by a microfluidizer and ultrasound were spray dried to produce nanoparticle encapsulated powders. Maltodextrin combined with a surface-active biopolymer (modified starch or whey protein concentrate) or a small molecule surfactant (Tween 20) was used as the wall material. Results showed that microfluidization was an efficient emulsification technique resulting in a powder with the highest retention (86.2%) of d-limonene, mainly due to its capability to produce emulsions with fairly small droplets (d43 of 700-800 nm) and narrow distributions, which had a good stability during the process. Among different emulsifiers used, although Tween 20 significantly reduced the emulsion size (d43 < 200 nm), the resulted powder had the poorest encapsulation efficiency. [ABSTRACT FROM AUTHOR]