Mini Spray Dryer Research Articles

Microencapsulation of Annona muricata L. seed extract for the control of Plutella xylostella

Insecticidal plants have stood out in Integrated Pest Management (IPM), associated with other control strategies, and therefore, the development of microencapsulated formulations, which make the active ingredient protected with slow and continuous release, becomes necessary. Thus, the present study aimed to develop, characterize and evaluate the lethal effect of the Microencapsulated Ethanolic Extract (MEE) from Annona muricata L. (Annonaceae) seeds on Plutella xylostella. MEE was developed in a B-290 BUCHI Mini Spray Dryer, using polymers starch, maltodextrin, gelatin and aerosil, and characterization was carried out through microparticle size and humidity, polydispersity index, morphologic analysis, Thermogravimetric analysis (TGA) and scanning electron microscope (SEM). MEE presented particle distribution with evident bimodal behavior, with diameters from 0.48 to 79.43 μm and polydispersity index equal to 6.414. Through SEM analysis, microparticles presented spherical and irregular shape, with smooth and rough/wavy, continuous, homogeneous surface, with variable size and external surface continuous in walls, with no apparent cracks. TGA demonstrated 5 decomposition stages, similar to the ethanolic extract. The estimated Lethal Concentrations (LC) for the ethanolic extract and MEE were: LC50 and CL99 of 0.204 and 5.675 g/L and 0.114 and 4.166 g/L, respectively. It could be concluded that the development of MEE was effective using the spray dryer method, with uniform microcapsules with insecticidal action able to be more soluble and persist the action of the active ingredient for longer times, improving its application in the field.

Hydrolyzed glucomannan as an encapsulant for various iron concentrations using spray drying method

Among the encapsulation methods, spray-drying is one of the simplest methods to protect iron from oxidation. Hydrolyzed glucomannan (HGM) has shown to have a potential as iron encapsulant in spray drying process due to its ability to form a barrier between the mineral and its surroundings. This work aimed to evaluate the effects of iron concentration (i.e., 20-50 ppm) on the spray dried powder properties using HGM as an encapsulant. The spray drying was conducted using Mini Spray Dryer B-290 Buchi. Feed temperature and aspirator were set at 100oC and 90% aspirator, with 1 mL.min-1 of flow rate. Increasing iron did not affect on encapsulation efficiency (98.66-99.4%) but allowed to push loading capacity from 30 to 61.5%. Lower iron concentration tended to result in more uniform particle size of the powders. Iron concentration insignificantly modified crystallinity and functional groups of the powder. Meanwhile, difference in thermal profile of spray-dry powders was observed due to iron concentration.

Precision forecasting of spray-dry desulfurization using Gaussian noise data augmentation and k-fold cross-validation optimized neural computing

Perceptron models have become integral tools for pattern recognition and classification problems in engineering fields. This study envisioned implementing artificial neural networks to forecast the performance of a mini-spray dryer for desulfurization activities. This work adopted k-fold cross-validation, a rigorous technique that evaluates model performance across multiple data segments. Several ANN models (21) were trained on data obtained from sulfation conditions, including sulfation temperature (120 °C–200 °C), slurry pH (4–12), stoichiometric ratio (0.5–2.5), slurry solid concentration (6%–14%) as the feed input and sulfur capture as the response. Three hundred synthetic datasets generated using the Gaussian noise data augmentation underwent a 10-fold cross-validation process before simulation on neural networks triggered by the logsig and tansig activation functions. The computation accuracy was further evaluated by altering the number of hidden cells from 2 to 10. The ANN architectures were assessed using statistical metrics such as mean square error (MSE), root mean square error (RMSE), mean absolute percentage error (MAPE), and the coefficient of determination (R 2) techniques. Overall, error estimation suggests cross-validation and data augmentation are critical in efficient neural network generalization. The logsig function trained with 10 hidden cells presented closer data articulation when mapped onto actual values.

Influence of Spray Drying Inlet Temperature on the Physical Properties and Antioxidant Activity of Black Garlic Extract Powder

Black garlic is a fermented product from garlic (Allium sativum L.) that is processed by heating fresh garlic at a certain temperature and humidity for several days. Black garlic has higher antioxidant activity and is rich in organosulfur compounds. Therefore, black garlic has an unpleasant taste and odor. Spray drying of black garlic extract is important for wider application, preservation and prolongation of its shelf-life. Black garlic powders were produced using SD-18A mini spray dryer. The purpose of this research was to evaluate the effect of inlet temperatures on the physical properties and antioxidant activity of aqueous black garlic powder. The inlet temperatures ranged from 165 to 225 °C, whereas other conditions were kept constant such as maltodextrin concentration (8 %) and feed flow rate (4.5 mL/min). The black garlic powders were examined for powder yield, moisture content, hygroscopicity, bulk density, wettability, antioxidant activity and total phenolic and flavonoid content. The optimal conditions for the drying process were achieved with an inlet temperature of 225 °C. An increase in the inlet temperature of the spray dryer has increased the powder yield, hygroscopicity, antioxidant activity and total phenolic and flavonoid content of the black garlic powder, but reduced the water content, bulk density and wettability of the spray-dried product. HIGHLIGHTS The best properties of black garlic powder were obtained at an inlet temperature of 225 °C The bioactive compounds of black garlic were stable at high temperatures The higher inlet temperatures increased antioxidant activity in black garlic powders GRAPHICAL ABSTRACT

Effects of Mimosa caesalpiniifolia pre-formulation on the intestinal barrier during sodium dextran sulfate-induced colitis in Wistar rats.

Anti-inflammatories, immunosuppressants, and immunobiological are commonly used in the treatment of inflammatory bowel disease. However, some patients do not present an adequate response or lose effective response during the treatment. A recent study found a potential anti-inflammatory effect of the hydroalcoholic extract of Mimosa caesalpiniifolia on trinitrobenzene sulfonic acid-induced colitis in Wistar rats. To evaluate the effects of M. caesalpiniifolia pre-formulation on the intestinal barrier using dextran sulfate sodium-induced colitis model. Leaf extracts were prepared in 70% ethanol and dried with a Buchi B19 Mini-spray dryer using 20% Aerosil® solution. Thirty-two male Wistar rats were randomized into four groups: basal control, untreated colitis, pre-formulation control (125 mg/kg/day), and colitis treated with pre-formulation (125 mg/kg/day). Clinical activity index was recorded daily and all rats were euthanized on the ninth day. Colon fragments were fixed and processed for histological and ultrastructural analyses. Stool samples were collected and processed for analysis of the short-chain fatty acid. Treatment with the pre-formulation decreased the clinical activity (bloody diarrhea), inflammatory infiltrate, and the ulcers. Pre-formulation did not repair the epithelial barrier and there were no significant differences in the goblet cells index. There was a significant difference in butyrate levels in the rats treated with the pre-formulation. The pre-formulation minimized the clinical symptoms of colitis and intestinal inflammation, but did not minimize damage to the intestinal barrier.

The Effect of Maltodextrin Concentration and Spray Dryer Drying Temperature on the Characteristics of Coconut Milk Powder

Coconut milk has a higher water content than other contents, so microbes can easily damage and spoil it. To obtain a low-moisture powder product, the liquid coconut milk was dried using a Buchi Mini Spray dryer B-290 with inlet temperatures of 150°C, 160°C, and 170°C. The researchers added maltodextrin to coconut milk, which had a ratio of grated coconut to the water of 1:3, in concentrations of 9%, 10%, 11%, 12%, and 13%. The addition of maltodextrin and the use of drying temperature did not significantly affect the pH, solubility, and percentage of product mass but did significantly affect the moisture content. The best operating conditions for producing coconut milk powder were at a maltodextrin concentration of 13% and a temperature of 170°C. Under these conditions, the produced coconut milk powder had a pH value of 6.12, a moisture content of 4.56%, a solubility of 98.74%, a product mass of 24.99 grams and an overall percentage of product mass of 21.32%.

Pulmonary delivery of spray-dried Nisin ZP antimicrobial peptide for non-small cell lung cancer (NSCLC) treatment

Nisin ZP is an antimicrobial peptide (AMP) produced by the bacterium Lactococcus lactis, and we have previously demonstrated anticancer activity in NSCLC (A549) cells. In this study, we formulated a nisin ZP dry powder (NZSD) using a spray dryer to facilitate inhaled delivery for the treatment of NSCLC. Nisin ZP was spray-dried with mannitol, l-leucine, and trehalose in a ratio of 75:15:10 using Büchi mini spray-dryer B-290 in different drug loadings (10, 20, and 30% w/w). NZSD powder revealed a good powder yield of >55% w/w with ≤3 % w/w moisture content and high nisin ZP drug loading for all the peptide ratios. The NZSD powder particles were irregularly shaped with corrugated morphology. The presence of an endothermic peak in DSC thermograms and attenuated crystalline peaks in PXRD diffractograms confirmed the semi-crystalline powder nature of NZSD. The anticancer activity of nisin ZP was maintained after fabricating it into NZSD powder and showed a similar inhibitory concentration to free nisin ZP. Stability studies indicated that NZSD powders were stable for three months at 4 and 25 ℃ with more than 90% drug content and semi-crystalline nature, as confirmed by DSC and PXRD. Aerosolization studies performed using NGI indicated an aerodynamic diameter (MMAD) within the desired range (1–5 µm) and a high fine particle fraction (FPF > 75%) for all peptide ratios, suggesting powder deposition in the lung's respiratory airways. In conclusion, a dry powder of nisin ZP was formulated using a spray dryer with enhanced storage stability and suitable for inhaled delivery.

Physicochemical characterization of sangorache natural colorant extracts (A<i>maranthus quitensis</i> L.) prepared via spray- and freeze-drying

<abstract> <p>In this study, we sought to prepare sangorache encapsulate (<italic>Amaranthus quitensis L.)</italic> by spray- and freeze-drying, using three different concentrations (3, 5 and 7%) of the encapsulating agent, maltodextrin. To atomize the powder, we used a Buchi mini spray-dryer B-290 with three inlet temperatures (140, 160 and 180 ℃) and a laboratory freeze dryer with a −0.8 bar pressure for 4 days. During atomization, the powders presented lower moisture content and water activity with the addition of maltodextrin; however, there were no significant changes in the moisture of the freeze-dried powders. Colorimetric analysis revealed that the luminosity (<italic>L</italic>) and chroma (<italic>C</italic>) values changed as maltodextrin concentration increased. The structures of particles were examined by scanning electron microscopy (SEM) SEM, and very different morphological characteristics resulted from the two drying methods. Also, apparent density, hygroscopy and dissolution testing revealed significant differences between the powders. Sangorache antioxidant compounds were preserved to a greater extent by applying low concentrations of the encapsulating agent and by the freeze-drying technique. The natural colorant from sangorache inflorescences could serve as an additive to improve food color in the industry.</p> </abstract>

Nanoparticles Obtained from Zein for Encapsulation of Mesalazine.

We encapsulated MSZ in zein nanoparticles (NP-ZN) using a desolvation method followed by drying in a mini spray dryer. These nanoparticles exhibited a size of 266.6 ± 52 nm, IPD of 0.14 ± 1.1 and zeta potential of -36.4 ± 1.5 mV, suggesting colloidal stability. Quantification using HPLC showed a drug-loaded of 43.8 µg/mg. SEM demonstrated a spherical morphology with a size variation from 220 to 400 nm. A FTIR analysis did not show drug spectra in the NPs in relation to the physical mixture, which suggests drug encapsulation without changing its chemical structure. A TGA analysis showed thermal stability up to 300 °C. In vitro release studies demonstrated gastroresistance and a sustained drug release at pH 7.4 (97.67 ± 0.32%) in 120 h. The kinetic model used for the release of MSZ from the NP-ZN in a pH 1.2 medium was the Fickian diffusion, in a pH 6.8 medium it was the Peppas-Sahlin model with the polymeric relaxation mechanism and in a pH 7.4 medium it was the Korsmeyer-Peppas model with the Fickian release mechanism, or "Case I". An in vitro cytotoxicity study in the CT26.WT cell line showed no basal cytotoxicity up to 500 μg/mL. The NP-ZN showed to be a promising vector for the sustained release of MSZ in the colon by oral route.

Manipulation of Spray-Drying Conditions to Develop an Inhalable Ivermectin Dry Powder.

SARS-CoV-2, the causative agent of COVID-19, predominantly affects the respiratory tract. As a consequence, it seems intuitive to develop antiviral agents capable of targeting the virus right on its main anatomical site of replication. Ivermectin, a U.S. FDA-approved anti-parasitic drug, was originally shown to inhibit SARS-CoV-2 replication in vitro, albeit at relatively high concentrations, which is difficult to achieve in the lung. In this study, we tested the spray-drying conditions to develop an inhalable dry powder formulation that could ensure sufficient antiviral drug concentrations, which are difficult to achieve in the lungs based on the oral dosage used in clinical trials. Here, by using ivermectin as a proof-of-concept, we evaluated spray-drying conditions that could lead to the development of antivirals in an inhalable dry powder formulation, which could then be used to ensure sufficient drug concentrations in the lung. Thus, we used ivermectin in proof-of-principle experiments to evaluate our system, including physical characterization and in vitro aerosolization of prepared dry powder. The ivermectin dry powder was prepared with a mini spray-dryer (Buchi B-290), using a 23 factorial design and manipulating spray-drying conditions such as feed concentration (0.2% w/v and 0.8% w/v), inlet temperature (80 °C and 100 °C) and presence/absence of L-leucine (0% and 10%). The prepared dry powder was in the size range of 1–5 μm and amorphous in nature with wrinkle morphology. We observed a higher fine particle fraction (82.5 ± 1.4%) in high feed concentration (0.8% w/v), high inlet temperature (100 °C) and the presence of L-leucine (10% w/w). The stability study conducted for 28 days confirmed that the spray-dried powder was stable at 25 ± 2 °C/<15% RH and 25 ± 2 °C/ 53% RH. Interestingly, the ivermectin dry powder formulation inhibited SARS-CoV-2 replication in vitro with a potency similar to ivermectin solution (EC50 values of 15.8 µM and 14.1 µM, respectively), with a comparable cell toxicity profile in Calu-3 cells. In summary, we were able to manipulate the spray-drying conditions to develop an effective ivermectin inhalable dry powder. Ongoing studies based on this system will allow the development of novel formulations based on single or combinations of drugs that could be used to inhibit SARS-CoV-2 replication in the respiratory tract.

Development of a microencapsulated cocoa (Theobroma cacao) - based product and evaluation of total phenolic compounds and antioxidant capacity

Oxidative stress is associated with the pathogenesis of several chronic diseases. Cocoa is a food rich in polyphenols, with high antioxidant properties, and is an important food in its fight. However, most polyphenols have low solubility, which impairs their biological action. Therefore, encapsulation through the spray drying technique can significantly improve these parameters by generating a protective layer using proteins and polysaccharides. Therefore, the objective of this work was to elaborate a cocoa-based product encapsulated with maltodextrin (CM) or goat milk whey (CW) and to evaluate the total phenolic compounds and their antioxidant capacity, as well as the particle size of the encapsulated product. Cocoa-based products were encapsulated using maltodextrin DE20 or goat whey using a B-290 mini spray dryer (Büchi Labortechnik, Flawil, Switzerland) in a 1:1 weight ratio. Subsequently, the antioxidant capacity was analyzed by the 2,2'-azino-bis (3-ethylbenzoatiazoline-6-sulfonic acid) (ABTS) method and total phenolic compounds using the phenol reagent Folin-Ciocalteu by spectrophotometry, as well as the size of the particle. The CW obtained a higher yield (33.11%) when compared to the CM (24.03%) in the spray dryer. Most of the particles (90%) present in the CM and CS had a size of 21.92 and 21.12 µM, respectively. CW had a higher content of phenolic compounds compared to CM (CM: 536 ± 8.0 vs. CW: 818 ± 77.0 mg GAE/100g dw, p = 0.05). No significant difference was observed in antioxidant capacity between samples (CM: 545 ± 26.0 vs. CW: 478 ± 18.0 µmol TE/100g dw, p = 0.114). The results showed that although CS has a higher content of phenolic compounds, both had the same antioxidant capacity.

Unsteadiness and resolution effects in experimentally verified simulations of a spray drying process

In this work, time-resolved three-dimensional numerical simulations supported by laboratory experiments aim to provide complementary information of the spray drying process, revealing pivotal details about the flow and particles dynamics. A drying model was implemented in the OpenFOAM open-source code and large-eddy simulations (LES) of the flow were performed on a BÜCHI Mini-spray dryer using real working conditions and input parameters. This work involved simulating a realistic number of particles (10,000 particles/s), higher than those commonly used. The simulation allowed to describe the average strong recirculation in the drying chamber, highlighting the wide spread of the residence time of each particle and how it affected its distribution. The percentage of product loss due to wall contamination is in good agreement with those in the experiment, showing that the simulations are reliable. This study illustrated the importance of unsteady and well-resolved simulations to gain insight into how flow characteristics affect particle trajectories and the product quality, giving information complementary to experimental measurements. Our observations also showed the importance of an appropriate resolution to describe flow features, those identification is crucial to design new devices with greater efficiency.

Enhanced anticancer effect of quercetin microparticles formulation obtained by spray drying

AbstractThis study unravels a formulation made of food‐based microparticles (MPs) able to control the release of quercetin, a natural anticancer compound, which activity is only limited by its poor aqueous solubility and consequent low bioavailability. To solve this issue, a spray‐dried micro delivery system was developed using a bench mini spray dryer B290 Buchi. The resulting MPs were only manufactured with food‐derived ingredients such as whey proteins and milk, avoiding the use of any other synthetic material. These microparticles were characterised with a testing campaign encompassing either the physical–chemical characterisation with SEM, DSC and DLS, or the technological and biological features with in vitro, ex vivo and in vivo studies, the latter being characterised by a human colon cancer xenograft model. These studies showed as the quercetin solubility and release rate improved when tested in condition mimicking oral administration, resulting in a general improvement of its bioavailability and the consequent anticancer activity. This study shows as the whey proteins may serves as natural adjuvant able to provide valuable technological features when used to manufactures micro carriers by spray drying.

Исследование процесса гранулирования нанопорошка системы W – Ni – Fe методом распылительной сушки

A method for obtaining nanopowder microgranules of the W – Ni – Fe system (composition of the VNJ-90) of a micron size range by spray drying of a suspension based on composite nanoparticles obtained by plasma chemical synthesis is considered. The parameters of operation of the Buchi Mini Spray Dryer B-290 spray drying laboratory unit with an ultrasonic nozzle have been experimentally determined, providing for the production of nanopowder microgranules of VNJ-90 with an output of the target fraction of 25 – 63 µm at the level of 65 %. The dependence of the size and morphology of the obtained granules on the choice of the dispersion medium, the concentration of the dispersed phase and the organic binder in the suspension is established. The effect of the suspension flow rate during spray drying on the yield of granules of a fraction of 25 – 63 µm was evaluated. The test of the manufactured experimental sample of nanopowder microgranules in the process of plasma spheroidization was carried out.

A Design of Experiment Approach to Optimize Spray-Dried Powders Containing Pseudomonas aeruginosaPodoviridae and Myoviridae Bacteriophages.

In the present study, we evaluated the effect of spray-drying formulations and operating parameters of a laboratory-scale spray-dryer on the characteristics of spray-dried powders containing two Pseudomonas aeruginosa bacteriophages exhibiting different morphotypes: a podovirus (LUZ19) and a myovirus (14-1). We optimized the production process for bacteriophage-loaded powders, with an emphasis on long-term storage under ICH (international conference on harmonization) conditions. D-trehalose-/L-isoleucine-containing bacteriophage mixtures were spray-dried from aqueous solutions using a Büchi Mini Spray-dryer B-290 (Flawil, Switzerland). A response surface methodology was used for the optimization of the spray-drying process, with the following as-evaluated parameters: Inlet temperature, spray gas flow rate, and the D-trehalose/L-isoleucine ratio. The dried powders were characterized in terms of yield, residual moisture content, and bacteriophage lytic activity. L-isoleucine has demonstrated a positive impact on the activity of LUZ19, but a negative impact on 14-1. We observed a negligible impact of the inlet temperature and a positive correlation of the spray gas flow rate with bacteriophage activity. After optimization, we were able to obtain dry powder preparations of both bacteriophages, which were stable for a minimum of one year under different ICH storage conditions (up to and including 40 °C and 75% relative humidity).

Study of a process of obtaining of protein preparation from sunflower seeds for application in food industry

The article deals with a study of processing methods of obtaining protein preparations from sunflower seeds. For obtaining of food-grade protein preparations from the defatted sunflower kernels phenolic compounds were additionally removed. Modern Russian and foreign literature sources devoted to the isolation of phenolic compounds from vegetable protein raw materials were analyzed. The objective of obtaining a light-colored food-grade protein preparation from sunflower seeds was solved through developing of a multi-stage extraction process with removal of various groups of non-protein compounds, including the stage of aqueous ethanol extraction and removal of phenolic compounds. Parameters of different stages of obtaining of protein substances from defatted sunflower seed kernels after removal of phenolic compounds were studied. These stages included alkaline extraction of protein and nitrogen-free extractives (NFE), separation of the insoluble residue, isoelectric precipitation of protein compounds from the clarified extract, neutralization of the protein suspension. Drying of the protein suspension was carried out on a laboratory spray installation Buchi Mini Spray Dryer with a temperature at the entrance of the dryer 180–190 ℃ and at the exit – up to 90 ℃. Protein preparations of light gray color were obtained with a crude protein content of 75,72% and 87,15% on dry matter basis, which corresponds to the crude protein content of commercial sunflower and soy protein concentrates. Solubility pattern of proteins and functional characteristics of finished protein preparations after spray drying have been analyzed. Based on the high fat-holding capacity and moderate fat-emulsifying properties of the obtained protein preparations it’s possible to recommend the obtained sunflower protein preparation for usage as a vegetable protein enricher and functional additive in food industry.

Microencapsulation of Anchovy Fish Oil (Engraulis encrasicolus) with Fish Protein (Equulites klunzingeri) Isolate: Nutritional Assessment

Fish protein isolates extracted from underutilised fish species were used for coating material of anchovy oils and their nutritive value was investigated in this study. For this purpose, Klunzinger’s ponyfish (Equulites klunzingeri) proteins were extracted by using pH shifting process. Micro particles were prepared with anchovy oil (Engraulis encrasicolus) as core material (10%), and as wall materials a ratio of 5% and 10% fish protein isolate (FPI) was used. Maltodextrin (DE: 18:20) was added to both groups in a ratio of 10%. The emulsions were fed immediately into a Buchi Mini Spray Dryer (B290, Switzerland). The inlet temperatures, feed rate and aspiration rate were maintained at 160 oC, 15 mL/min and 35m3/h, respectively. The lipid, protein and moisture contents of anchovy oil microcapsules containing 5% FPI and 10% FPI were found as 43.76-43.09%, 4.34- 9.82% and 3.95-3.92%, respectively. The main amino acids in microcapsule samples were lysine, glutamic acid, and leucine which constituted in the range of 349-578 mg/100 g sample for microcapsules containing 5% FPI, and 805-1547 mg/100 g sample for microcapsules containing 10% FPI. In addition to that, essential and non-essential amino acids (E/NE) ratio for microencapsulated fish oil with 5% FPI and 10% FPI were determined 0.92 and 0.95, respectively. As a result of this study, it can be concluded that the addition of fish protein isolate enhanced the nutritive value of microencapsulated fish oil.

Obtaining dry protein concentrates from secondary gelatin products

The article presents the investigation of the chemical composition of a collagen-containing broth obtained during gelatin production at the stage of defatting bony raw material. Collagen broth is a minor by-product from gelatin production. The aim of the research is to analyze the effect of the duration of the hydrothermal treatment of collagen raw materials on the concentration of high-protein broths by using spray drying. To carry out a set of experimental studies they used broth obtained by the method of hydrothermal treatment of bone at a temperature of 95±5°C for 90 to 180 minutes and its dry concentrate obtained later at the Mini Spray Dryer B-290 laboratory spray drying model (Buchi, Sweden). According to the research results, it has been revealed that the duration of the hydrothermal treatment affects the indicators of fat, protein, and dry matter content in broths. When being treated for 90 minutes, the dry matter content is in the range of 8,1 %, which is 46 % less than with a treatment time of 180 minutes. When the duration of the hydrothermal treatment of raw materials increases, the gelation time of the obtained broths reduces at temperature conditions of 4±2°C. After the spray drying process physicochemical parameters of the obtained dry collagen concentrates have been determined. In the dry concentrate the dependence of the indicator of the content of the mass fraction of protein on the duration of the hydrothermal treatment of broths is observed, the values range from 64,19 % to 82,89 %. The gelling capacity of all samples is high. The obtained dry concentrates are in the form of white to light cream color homogeneous powder.

Functional and Oxidative Quality Characterization of Spray-Dried Omega-3-Enriched Milk Powder

In the present study, fish oil (FO) and wall material were supplemented to milk to produce spray-dried powder (SDP). Furthermore, the mandate of the study was to enlighten the effect of spray-drying (SD) operating conditions on functional and oxidative quality of produced SDP samples. Purposefully, the cow milk was supplemented with 3% FO as omega-enriched source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) for development of milk and FO blends (MFOBs). The lecithin was used as an emulsifier and maltodextrin was supplemented as the wall material (WM) in the MFOBs. Initially, the FO, milk fat (MF), and MFOB samples were characterized for EPA, DHA, and peroxide value (PV) before the SD. The SD of MFOB samples was carried out to produce SDP samples by using a mini spray dryer. Central composite design (CCD) with face-centered rotation was used to optimize SD independent conditions such as inlet air temperature (IAT), pump speed (PS), maltodextrin percentage (MD), and needle speed (NS) in the ranges of 160–200°C, 3–9 mL/min, 10–30%, and 5–9 s, respectively. The encapsulation efficiency (EE) ranged between 89.30 and 81.57%. The EPA and DHA retentions were in the ranges of 2.19–1.87 g/100 g and 3.20–2.75 g/100 g, respectively. The highest results for responses were observed on the following conditions: IAT was 160°C, PS was 9 mL/min, MD was 30%, and NS was 9 s, respectively; the minimum values of response factors were obtained on the following conditions: IAT was 200°C, PS was 3 mL/min, MD was 10%, and NS was 5 s, respectively. The percent losses of EPA and DHA were noted in the range of 2–18%. The IAT was observed as main factor for FA reduction in SDP samples. The SDP samples were stable, and low rate of peroxide values was noted. Overall, spray drying can be potentially used to incorporate the essential fatty acids in milk to produce stable SDP for food applications.

Spray drying of colloidal suspensions: Coupling of particle drying and transport models with experimental validations

A numerically effective approach was developed for the modeling of spray-drying of colloidal suspensions. This approach was based on the integration of two models. The first is a phenomenological and radially symmetric model accounting for the drying of single-droplets, while the second employs computational fluid dynamics (CFD) simulations to account for the gas flow conditions and atomization in a spray dryer. Experiments were also conducted on single suspension droplets trapped in an acoustic field as well as on droplets in a mini-spray dryer. The predictions of the models were found to be in reasonable agreement with the experimental data, in terms of droplet shrinking and buckling, particle yield, and spatial distribution in the spray dryer mockup.