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Summary: Preserving food products from oxidation improves their quality and stability. This study compares the effects of storage on L‐theanine, caffeine, moisture content and antioxidant activity of spray‐dried and freeze‐dried white tea infusions. The antioxidant activities of both dried infusions were restored over a 60‐day storage. On Day 60, the L‐theanine and caffeine levels of the freeze‐dried samples were respectively 1.45 ± 0.03 mg mL−1 and 2.23 ± 0.04 mg mL−1 compared with 1.16 ± 0.03 mg mL−1 and 1.97 ± 0.01 mg mL−1 on Day 0. In the spray‐dried samples, the L‐theanine was 0.32 ± 0.01 mg mL−1 on Day 60 and 0.36 ± 0.02 mg mL−1 on Day 0, while caffeine remained unchanged. Regarding undried/control samples, L‐theanine and caffeine declined from respectively 0.29 ± 0.0004 mg mL−1 and 0.33 ± 0.01 mg mL−1 on Day 0 to 0.2 ± 0.001 mg mL−1 and 0.26 ± 0.02 mg mL−1 on Day 60, associated with a decrease in DPPH activity from 75.87% (Day 0) to 15.34% (Day 60). Freeze‐drying and spray‐drying tea infusions yielded functional products with stable antioxidant activity and moisture. Both drying techniques are reliable for preserving tea preparations. [ABSTRACT FROM AUTHOR]

Spray drying (SD) and freeze drying (FD) represent common methods utilized across various industries to achieve powdered final products. Electrostatic spray drying (ESD) is an emerging alternative as a continuous process to dry sensitive products without degradation, challenging the established drying techniques. This study aims to explore the efficacy of this process (ESD) in preserving the integrity of active components like oils, lactic acid bacteria (LAB), and enzymes. Additionally, a life cycle assessment (LCA) of these three drying technologies was conducted for a comprehensive evaluation. In oil encapsulation, the study showed that oxidation was significantly influenced by the formulation and the drying processes employed, where higher encapsulation efficiency resulted in lower degradation. This was observed, for instance, in the saponin composition dried with ESD. For LAB encapsulation, the results demonstrated higher preservation using FD and ESD. However, the impact of climate change using FD is twice superior to the ESD process. Finally, for enzyme application, β-gal activity was retained maximally while encapsulating using skim milk or maltodextrin. Specifically, regardless of drying technique, maltodextrin exhibited a maximum retention of β-gal activity, exceeding 30%. In all the case studies, ESD proved to excel in encapsulating thermosensitive actives, highlighting superior retention of native viability and properties compared to SD. Additionally, ESD generated results comparable to those achieved with FD. Therefore, ESD appears to be a promising method for high powder quality and a more sustainable process than FD and SD. [Display omitted] • Introduction of ESD compared to SD & FD was performed. • Effects of formulation and scales were studied. • LCA was conducted to evaluate powder production scenarios. • ESD was the most efficient to encapsulate thermosensitive active. [ABSTRACT FROM AUTHOR]

Lactobacillus delbrueckii subsp. bulgaricus and Lactiplantibacillus plantarum are two lactic acid bacteria (LAB) widely used in the food industry. The objective of this work was to assess the resistance of these bacteria to freeze- and spray-drying and study the mechanisms involved in their loss of activity. The culturability and acidifying activity were measured to determine the specific acidifying activity, while membrane integrity was studied by flow cytometry. The glass transitions temperature and the water activity of the dried bacterial suspensions were also determined. Fourier transform infrared (FTIR) micro-spectroscopy was used to study the biochemical composition of cells in an aqueous environment. All experiments were performed after freezing, drying and storage at 4, 23 and 37 °C. The results showed that Lb. bulgaricus CFL1 was sensitive to osmotic, mechanical, and thermal stresses, while Lpb. plantarum WCFS1 tolerated better the first two types of stress but was more sensitive to thermal stress. Moreover, FTIR results suggested that the sensitivity of Lb. bulgaricus CFL1 to freeze-drying could be attributed to membrane and cell wall degradation, whereas changes in nucleic acids and proteins would be responsible of heat inactivation of both strains associated with spray-drying. According to the activation energy values (47–85 kJ/mol), the functionality loss during storage is a chemically limited reaction. Still, the physical properties of the glassy matrix played a fundamental role in the rates of loss of activity and showed that a glass transition temperature 40 °C above the storage temperature is needed to reach good preservation during storage. Key points: • Specific FTIR bands are proposed as markers of osmotic, mechanic and thermal stress • Lb. bulgaricus CFL1 was sensitive to all three stresses, Lpb. plantarum WCFS1 to thermal stress only • Activation energy revealed chemically limited reactions ruled the activity loss in storage [ABSTRACT FROM AUTHOR]

The present study compared vacuum drum drying (VDD) and conventional spray drying (SD) for solidifying crystalline ABT-199 nanosuspensions into redispersible oral drug products. The aim was to optimize formulation compositions and process conditions to maintain nanoparticle size after tablet redispersion. The impact of drug load (22%, 33%, 44%) and type of drying protectant (mannitol, mannitol/trehalose mix (1:1), trehalose) on redispersibility and material powder properties were investigated. Moreover, compression analysis was performed assessing the influence of compaction pressure on primary nanocrystal redispersibility and tablet disintegration. Higher drug loads and lower drying protectant levels resulted in particle growth, confirming a drug load dependence on redispersibility behavior. Notably, all drying protectants showed similar protection properties at properly chosen drying process parameters (Tg-dependent), except when VDD was used for mannitol formulations. Differences between the applied drying processes were observed in terms of downstream processing and tabletability: mannitol-containing formulations solidified via VDD showed an improved processability compared to formulations with trehalose. In conclusion, VDD is a promising drying technique that offers advantageous downstream processability compared to SD and represents an attractive novel processing technology for the pharmaceutical industry. As demonstrated in the present study, VDD combines higher yields with a leaner manufacturing process flow. The improved bulk properties provide enhanced tabletability and enable direct compression. [ABSTRACT FROM AUTHOR]

Traditional drying processes used to dry high-quality baijiu yeast-Sporidiobolus johnsonii A do not offer advantages such as high efficiency, high survival rate, and low energy consumption. Therefore, we investigated the damage inactivation mechanism of S. johnsonii A for the spray drying process. Subsequently, the combined drying process and equipment for spray + vacuum-microwave-vibration were designed. The results reveal selective permeability damage and collapse owing to gel and anti-hexagonal phase transitions of the cell membrane, resulting in S. johnsonii A inactivation and massive inactivation at 52 °C with a water content of 0.21 and at 71 °C with a water content of 0.07, respectively. The combined drying process developed in this study successfully dried S. johnsonii A with high efficiency (1.1 h) and excellent quality (85.4 ± 2 %). [ABSTRACT FROM AUTHOR]

The final particle moisture content of ceramic slurry spray drying affects the processing, product quality, and process energy consumption. While the real-time moisture content determination is very difficult for spray drying process due to nonlinear, severe lag, interference factors, and complexity of the systems, the high temperature, high humidity drying environment and short drying process. In current work, an improved moth optimization (IMFO) algorithm combined with backpropagation neural network (BPNN) was proposed to predict the moisture content of ceramic slurry particles during spray drying. The performance of the model is trained and tested. Results demonstrate that IMFO has better convergence ability and speed compared to other algorithms such as particle swarm optimization (PSO) and gravitational search algorithm (GSA). The IMFO-BPNN model achieves a MAE of 0.0293, RMSE of 0.0383, and R2 value of 0.9113, outperforming the prediction performance of BPNN and MFO-BPNN models. The absolute error rate of the IMFO-BPNN model (0–5%) is lower compared to BPNN (5–10%) and MFO-BPNN model (>10%), showcasing superior accuracy in predicting moisture content. This mathematical model established in the study provides an efficient, accurate, and nondestructive method for predicting the drying endpoint of ceramic slurry spray drying. [ABSTRACT FROM AUTHOR]

The aim of this article is to model CFD (Computational Fluid Dynamics modeling), a spray dryer, for which experimental studies were conducted, and the general parameters of the drying process in the software environment ANSYS, FLUENT were determined. The numerical model should meet most requirements, such as the modeling of spray dryers. Thus, the purpose of the basic model is to provide the principles of a modern industrial approach to the modeling of spray dryers at moderate computational costs, while laying the foundation for further development and evaluation of relevant aspects of modeling spray systems equipped with disk sprayers. [ABSTRACT FROM AUTHOR]

Knowledge of drying history and structure formation is essential for the quality of spray dried products. In this study, these factors are investigated using the denaturation of phycocyanin. By studying the denaturation kinetics of this marker, added to the feed solution, it was found that denaturation can neither occur in the constant drying rate regime nor in the final stage of drying, as the temperature (T < 60 °C) and the moisture content (aw < 0.6) is too low, respectively. Thus, it was concluded that phycocyanin denaturation is influenced by the crust formation during spray drying. This was applied to pilot scale spray drying, where the effect of air inlet and outlet temperature, air moisture content, feed solids content and particle residence time was investigated. The qualitative agreement between phycocyanin denaturation and the determined particle structure provides a basis for the validation of models, predicting structure development during drying. [ABSTRACT FROM AUTHOR]

Honey is an excellent alternative to be used in different applications by the food, pharmaceutical, and cosmetics industries. However, the use of honey in its liquid form can present several disadvantages due to its high viscosity and density. In addition, honey can naturally crystallize during storage time, limiting its application in new products by industries. Thus, an alternative to using liquid honey in industry is the powder form. The objective of this study was to obtain honey powder by spray drying using a plant-based protein as a carrier. The honey used as raw material showed acceptable physicochemical parameters by the legislation of honey quality control, such as pH of (4.0 ± 0.1), the water content of (20.70 ± 0.3) g/100 g, ash of (0.48 ± 0.02) g/100 g, the fructose content of (35.42 ± 0.14) g/100 g, (43.05 ± 0.46) g/100 g for glucose, (0.56 ± 0.02) g/100 g for sucrose, and 5-hydroxymethylfurfural (HMF) value of (37.47 ± 1.04) mg/kg of honey, leading to the production of the honey powder. The mixture of fresh honey and plant-based protein was made with dispersions of 15, 16 and 18 g/100 g of honey using isolated rice protein as a carrier (total solid at 30 g/100 g d.b.). Finally, the honey powder produced was physicochemically characterized. The dispersion with 16 g/100 g of honey achieved an intermediary sugar/honey recovery of 35.93 ± 0.82% and 68.54 ± 2.16% of total protein recovery, and the spray drying yield was satisfactory > 50%. The overall results suggested that this dispersion is the ideal formulation when commercialization of the honey powder as an ingredient is intended. [ABSTRACT FROM AUTHOR]

In recent years, many fast drying techniques such as spray-drying are being explored as alternatives to biopharmaceutical freeze-drying. Thus, it is essential to understand how the processability of commonly used excipients will be affected when these new techniques are employed. This study reports a series of observations outlining how the thermally-induced oxidative degradation of polysorbates (PS) evolves in liquid to solid transitions, such as those expected in spray-drying. Firstly, the impact of different evaporation rates on the oxidative degradation of aqueous solutions of two different PS types namely, PS20 and PS80, were screened via evaporative solvent casting. The latter revealed that the evaporation rate could critically impact the rate-limiting steps of PS thermal oxidation. In addition, the potential of saccharides as excipients to mitigate the thermal oxidation of PS80 under slow and fast evaporation conditions was investigated. Five different saccharide excipients were screened, i.e., trehalose dihydrate, maltodextrin, hydroxypropyl-β-cyclodextrin, and Dextran 40. Under slow evaporation conditions, only trehalose dihydrate seemed to be beneficial in avoiding the thermal oxidation of PS80. For fast evaporation conditions, hydroxypropyl-β-cyclodextrin prevented the oxidative degradation of PS80. This implies that distinct strategies to mitigate PS oxidative degradation might be necessary depending on the drying process and rates. [ABSTRACT FROM AUTHOR]

A considerable number of grape pomaces are generated annually. It represents a rich source of bioactive compounds, such as phenolic compounds and anthocyanins. Pressurized liquid extraction (PLE) has emerged as a green technology for recovering bioactive compounds from vegetal matrixes. In our study, PLE parameters (temperature, number of cycles, and rinse volume) have been studied to produce grape pomace extracts with high bioactive content using an experimental design. The experimental data obtained were adjusted to linear and quadratic models. The first-order model was better in predicting anthocyanins contents (TA, R2 = 0.94), whereas the second-order model was predictive for total phenolic compounds (TPC, R2 = 0.96). The main process parameter for the recovery of bioactive compounds was temperature, and the results showed opposing behaviors concerning TPC and TA, as it is difficult to optimize conditions for both. The extract containing the higher concentration of TPC (97.4 ± 1.1 mg GAE/g, d.b.) was encapsulated by spray-drying using maltodextrin as wall material. Particles presented with a spherical shape (~7.73 ± 0.95 μm) with a recovery yield of 79%. The results demonstrated that extraction followed by encapsulation of grape pomace extract is a good strategy to simplify future applications, whether for food, cosmetics or pharmaceutical fields.

This study aims to improve the quality of spray-drying Lonicera edulis powder. Maltodextrin, β-cyclodextrin and whey protein were used as the compound additives. A systematic investigation was implemented to clarify the effects of compound additives on the physicochemical properties of spray-drying Lonicera edulis powder. The golden split formulation test was designed as a single-factor test. An analysis was made on the effects of low-temperature air inlet temperature (50- 90 °C) on anthocyanin retention rate, powder collection rate, and water content of Lonicera edulis powder. The results show that the powder collection rate was as high as 37.96% in the first golden split formulation test, when the mass ratios of maltodextrin and β-cyclodextrin were 85.4% and 14.6% (test point T4), respectively. There was an increasing trend in the glass transition temperature (Tg), water solubility index, bulk density, L* value, a* value, and color difference ΔE of Lonicera edulis powder, with the increase in the mass ratio of maltodextrin in the feed solution, while the water content, anthocyanin content, and b* value showed a decreasing trend. A comparison was then made on the physicochemical index of each test point in the first golden split. The test point T4 was selected for the second golden split formulation test; The highest powder collection rate (40.11%) was achieved, when the ratios of maltodextrin, β-cyclodextrin and whey protein were 72.9%, 12.5%, and 14.6% (test point E4), respectively. The contents of water and anthocyanin tended to increase in the prepared Lonicera edulis powder, with an increase in the proportion of whey protein in the feed solution, while there was a decrease in the glass transition temperature (Tg), water solubility index, L* value, a* value, b* value and color difference ΔE. A comparison was also made on the physicochemical indexes of single additive T6 (maltodextrin mass ratio of 100%), T7 (β-cyclodextrin mass ratio of 100%), E7 (whey protein mass ratio of 100%), the best composite additives T4 (in the first golden section), and E4 (in the second golden section) test points. The composite additives significantly improved the powder collection rate of Lonicera edulis powder via a synergistic effect (P<0.05). The physical and chemical indexes (such as water content, water solubility index, and bulk density) were all close to the optimum level, indicating that the composite additives improved the comprehensive quality of Lonicera edulis powder better than that of a single additive. The additives in the feed solution shared their physical and chemical properties during spray drying and then interacted with each other with the biological activity. The low-temperature spray drying test showed that the powder collection rate and water content were negatively correlated with the increase in inlet air temperature. The test site E4 presented a high anthocyanin retention rate (89.94%) while maintaining a high powder collection rate at 90 oC. The spectral and proton density images were captured in the Lonicera edulis stock and sample solution at each test site. Additives were added to increase the content of strong bound water, weak bound water and immobile water in the feed and liquid. The freedom of free water was also reduced for the stable hydrate, in order to improve the droplet coalescence resistance, the overall Tg of feed and liquid, and the powder collection rate. The water distribution of the sample solution was much more uniform, while the whole solution was more stable after pretreatment with compound and single additive, which was conducive to the preparation of blue Lonicera edulis powder by spray drying. Fourier transform infrared spectroscopy (FTIR) analysis showed that the compound additives formed the intermolecular hydrogen bonds in Lonicera edulis powder, thus protecting the anthocyanins and other active substances. The findings can provide theoretical support and reference for the production of Lonicera edulis spray drying. [ABSTRACT FROM AUTHOR]

A considerable number of grape pomaces are generated annually. It represents a rich source of bioactive compounds, such as phenolic compounds and anthocyanins. Pressurized liquid extraction (PLE) has emerged as a green technology for recovering bioactive compounds from vegetal matrixes. In our study, PLE parameters (temperature, number of cycles, and rinse volume) have been studied to produce grape pomace extracts with high bioactive content using an experimental design. The experimental data obtained were adjusted to linear and quadratic models. The first-order model was better in predicting anthocyanins contents (TA, R2 = 0.94), whereas the second-order model was predictive for total phenolic compounds (TPC, R2 = 0.96). The main process parameter for the recovery of bioactive compounds was temperature, and the results showed opposing behaviors concerning TPC and TA, as it is difficult to optimize conditions for both. The extract containing the higher concentration of TPC (97.4 ± 1.1 mg GAE/g, d.b.) was encapsulated by spray-drying using maltodextrin as wall material. Particles presented with a spherical shape (~7.73 ± 0.95 μm) with a recovery yield of 79%. The results demonstrated that extraction followed by encapsulation of grape pomace extract is a good strategy to simplify future applications, whether for food, cosmetics or pharmaceutical fields. [ABSTRACT FROM AUTHOR]

Mint (Mentha spicata L.) is a herbaceous plant from the Lamiaceae family, with numerous varieties. Fresh leaves have high moisture, which enables microbial growth and renders them perishable. Thus, drying aromatic plants, such as mint, is an alternative to increase their shelf life. Therefore, the objective of this work was to study the drying of mint, with and without blaching, by spray drying and to evaluate the moisture, color, hygroscopicity, bulk density, chlorophyll, carotenoids, phenolics, particle size distribution and morphology of the obtained powder. Thus, in addition to the effect of using blanching or not, the influence of temperature, drying airflow, and solution feed flow was investigated. Blanching contributed to a greater retention of carotenoid pigments and higher levels of chlorophyll and total phenolics. The highest observed yield value was 50.24% for the powder obtained with blanching produced at lower temperatures, which was associated with a high flow rate of the solution. In conclusion, this research sheds light on the potential of using blanching in conjunction with spray drying to conserve mint's bioactive components, offering practical applications in food and pharmaceutical industries, and potentially contributing to enhanced shelf life and product quality. Practical applications: Mint is renowned for its medicinal and sensory attributes; however, its inherent perishability post‐harvest necessitates exploring conservation techniques. While dried mint is available on the market, many drying processes remain artisanal and need more control over conditions to prevent the loss of its essential properties. Hence, this study sought to investigate mint drying through spray drying and the effect of process conditions on the product properties. Another essential point also evaluated was the impact of bleaching as a pre‐treatment. Integrating bleaching techniques with drying proved instrumental in preserving carotenoid pigments elevating chlorophyll and total phenolic levels. These findings offer significant potential for the food industry. Furthermore, the pharmaceutical industry stands to gain by harnessing mint's preserved bioactive compounds for medicinal applications. Overall, this research provides invaluable insights for optimizing mint preservation methods and promises to enhance product quality and shelf life across various industrial domains. [ABSTRACT FROM AUTHOR]

Excess vapor content in the spray-drying system leads to various issues such as undesired agglomeration or caking of products. The majority of the drying in spray-dryers occurs during the initial phase, where the feed is still liquid. Drying kinetics is very sensitive to the droplet size, and the droplet size is heavily influenced by collisions that can coalesce or split droplets. An analytical model is developed to examine the role of droplet collisions on drying kinetics, and the evaporation rate during the first phase of drying. In addition, droplet collision dynamics are implemented into an Eulerian-Lagrangian framework, where droplets are tracked in the Lagrangian frame, and the background gas is modeled as a continuum. The collision dynamics is capable of predicting the outcome of collisions based on a regime map constructed from the experimental data from the literature. The relative velocity and the Weber number between colliding droplets affect whether droplets coalesce or split into satellite droplets. The modeling framework includes fully coupled interphase heat transfer between the droplet and gas phases. The analytical and numerical models are then used to analyze a simplified pseudo-1D spray system. Both models show a linear relationship between the Weber number and the evaporation rate at low droplet number densities. Further, comparing both methods' results reveals droplet number density as another critical factor influencing the evaporation rate. It is shown that at high droplet number densities, the relationship between the evaporation rate and the Weber number becomes non-linear, and at extremely high droplet number densities, the evaporation rate decreases even at high Weber numbers. [ABSTRACT FROM AUTHOR]

Compared with the commonly used technique of freeze-drying, spray drying has lower energy costs. However, spray drying also has a fatal disadvantage: a lower survival rate. In this study, the survival of bacteria in a spray-drying tower decreased as the water content was reduced. The water content of 21.10% was the critical point for spray drying Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) sp1.1 based on sampling in the tower. Based on the relationship between the moisture content of spray drying and the survival rate, the water content of 21.10% was also the critical point for the change in the survival rate during spray drying. Proteomic analysis was used to investigate the reasons for L. bulgaricus sp1.1 inactivation during and after spray drying. Gene Ontology (GO) enrichment revealed that differentially expressed proteins were mainly associated with the cell membrane and transport. In particular, proteins related to metal ion transport included those involved in the transport of potassium, calcium and magnesium ions. The protein–protein interaction (PPI) network revealed that Ca++/Mg++ adenosine triphosphatase (ATPase) may be a key protein. Ca++/Mg++ ATPase activity decreased substantially during spray drying (p < 0.05). Supplementation with Ca++ and Mg++ significantly increased the expression of ATPase-related genes and enzyme activity (p < 0.05). The Ca++/Mg++ ATPase activity of L. bulgaricus sp1.1 was enhanced by increasing the intracellular Ca++ or Mg++ concentration, thus increasing the survival of spray-dried LAB. Bacterial survival rates were increased to 43.06% with the addition of Ca++ and to 42.64% with the addition of Mg++, respectively. Ca++/Mg++ ATPase may be the key to the damage observed in spray-dried bacteria. Furthermore, the addition of Ca++ or Mg++ also reduced bacterial injury during spray drying by enhancing the activity of Ca++/Mg++ ATPase. [ABSTRACT FROM AUTHOR]

[Display omitted] Despite extensive research in spray drying of biopharmaceuticals, identifying the optimal formulation composition and process conditions to minimize the various stresses a biopharmaceutical undergoes during this drying process. The current study extends previous research on investigating how spray drying processing and solution composition can affect the stability of monoclonal antibodies (mAbs) in reconstituted solutions for subcutaneous injections. The decoupling process stresses on a model mAb (mAb-A) compared to the effect of coupled spray-drying stresses revealed that excipients and protein concentration had a more pronounced effect on stabilizing mAb-A against shear and thermal/dehydration stresses than spray drying operating conditions. These results prompted the continuation of the study, with the aim to investigate in greater depth the effect of mAb-A concentration in the formulation designated to spray-drying and then the effect of type and the concentration of individual excipients (sugars, amino acids and surfactants). The outcomes of this investigation suggest that a general increase in the concentration of excipients, particularly surfactants, correlates with a reduction in aggregation and turbidity observed in the reconstituted spray-dried mAb-A powders. These results, contribute to the identification of a suitable composition for a spray-dried mAb-A powder that ensures robust stability of the protein in reconstituted solutions intended for subcutaneous injection. This valuable insight has important implications for advancing the development of pharmaceutical formulations with enhanced stability and efficacy. [ABSTRACT FROM AUTHOR]

[Display omitted] Spray drying is increasingly being applied to process biopharmaceuticals, particularly monoclonal antibodies (mAbs). However, due to their protein nature, mAbs are susceptible to degradation when subjected to various stresses during a drying process. Despite extensive research in this domain, identifying the appropriate formulation composition and spray drying conditions remains a complex challenge, requiring further studies to enhance the understanding on how process and formulation parameters impact mAb stability in reconstituted solutions. This research aims to explore spray drying as technique for producing pharmaceutical mAbs-based powders intended for reconstitution and subcutaneous injection. In the initial phase of this study, using a model mAb (mAb-A), the influence of dissociated and coupled process stresses on protein stability after solution reconstitution was investigated. The findings revealed a detrimental interplay of mechanical, interfacial, and thermal/dehydration stresses on mAb-A stability, notably characterized by an increase in protein aggregation. Subsequently, in a second phase, the study delved into the impact of spray drying processing conditions, the level of excipients, and protein concentration on mAb-A aggregation in reconstituted solutions. The obtained results highlighted the critical role of formulation composition as a parameter deserving further study, specifically concerning the selection of type and concentration of stabilizers to be added in the liquid mAb-A solution to be dried. [ABSTRACT FROM AUTHOR]

Beta-lapachone (βlap) is a naphthoquinone derived from Lapachol, a substance extracted from the Bignoniaceae family of trees, genus Tabebuia; found in the Northern and Northeastern regions of Brazil. βlap shows excellent pharmacological activity as an antiparasitic, antitumor, and anti-inflammatory drug, but its water solubility is low, which decreases its bioavailability. This work aims to evaluate the solubility and dissolution rate of βlap from solid dispersions obtained by the Spray Drying technique and compare them with the physical mixture (PM) of compounds. βlap solid dispersions were prepared with polyethylene glycol (PEG 6000) and polyvinylpyrrolidone (PVP K30) at 1: 2 (w/w) ratio and characterized by thermal analysis [differential scanning calorimetry (DSC)], X-ray powder diffraction (XRPD), Fourier transform infrared (FTIR), Scanning electron microscopy (SEM), solubility tests, dissolution profile assays and analyzed by mathematical models to link to the system properties. βlap/PVP solid dispersion provided a 15-fold increase in dissolution rate compared to pristine βlap in the first 5 min. The release constants obtained from Korsmeyer–Peppas and Weibull models demonstrate that βlap is released more rapidly from the PVP system produced by Spray Drying than by PM. The thermal analysis suggests that the βlap was successfully encapsulated into spherical shape and uniform size distribution microparticles produced by SD/PVP, as shown by the SEM technique. In addition, it afforded about 9-fold higher solubility than the free βlap. The results of DSC and XRD showed a tendency of the βlap crystallinity to decrease. FTIR showed intermolecular interaction between drug and polymer molecules (PVP and PEG). Thus, the results suggest that βlap/PVP-based solid dispersions can be successfully applied in pharmaceutical formulations. [ABSTRACT FROM AUTHOR]

We report a spray-drying method to fabricate silver nanoparticle (AgNP) aggregates for application in surface-enhanced Raman spectroscopy (SERS). A custom-built system was used to fabricate AgNP aggregates of four sizes, 48, 86, 151, and 218 nm, from drying droplets containing AgNPs atomized from an AgNP suspension. Sample solutions of Rhodamine B (RhB) at 10–6, 10–8, and 10–10 M concentrations were dropped onto the AgNP aggregates as probe molecules to examine the enhancement of the Raman signals of the RhB. The ordering of the analytical enhancement factors (AEFs) by aggregate size at a 10–6 M RhB was 86 nm > 218 nm > 151 nm > 48 nm. When RhB concentrations are below 10–8 M, the 86 and 151 nm AgNP aggregates show clear RhB peaks. The AEFs of the 86 nm AgNP aggregates were the highest in all four aggregates and higher than those of the 218-nm aggregates, although the 218-nm aggregates had more hot spots where Raman enhancement occurred. This finding was attributable to the deformation and damping of the electron cloud in the highly aggregated AgNPs, reducing the sensitivity for Raman enhancement. When RhB was premixed with the AgNP suspension prior to atomization, the AEFs at 10–8 M RhB rose ~ 100-fold compared to those in the earlier experiments (the post-dropping route). This significant enhancement was probably caused by the increased opportunity for the trapping of the probe molecules in the hot spots. [ABSTRACT FROM AUTHOR]

This study investigated droplet shrinkage and crystallization behaviors of easily crystalline mannitol model material. Different sized droplets were generated from feeds of different solid contents and dried into uniform microparticles via a microfluidic jet spray dryer. The droplet shrinkage behavior was characterized by comparing the size of dried microparticles and initially atomized droplets. Morphology and polymorphs of the microparticles were analyzed via SEM and XRD. Droplet shrinkage and crystallization behaviors were shown to be closing related to size, morphology, and polymorph of the spray dried microparticles. Droplets with small size or low solid content followed perfect shrinkage behavior, while droplets with larger sizes or higher solid contents demonstrated less shrinkage due to the earlier precipitation of a crust. Dense, partially hollow, or hollow spherical particles with different polymorphs (mixture of α- and β-mannitol or fully β-mannitol) were obtained depending on the process parameters, indicating the occurrence of different crystallization behaviors. [ABSTRACT FROM AUTHOR]

The goal of this study was to investigate the influence of the emulsifier system on the changes in oil droplet size occurring during the drying step of spray drying of emulsions. Atomization and spray drying experiments were performed with emulsions stabilized with whey protein isolate (WPI) alone or in combination with low molecular weight emulsifiers (lecithin, mono‐ and diglycerides (MoDi), and citrem). Oil droplet coalescence was observed for the systems WPI/Citrem and WPI/MoDi, as the d90,0 increased from 0.86 ± 0.16 and 1.67 ± 0.35 µm after atomization to 1.83 ± 0.24 and 1.90 ± 0.17 µm after drying, respectively. Oil droplets stabilized with WPI or WPI/Lecithin remained stable during drying. Measurements of dilatational rheology of the interfacial film showed that phase angle values increase in the order WPI/Lecithin < WPI < WPI/Citrem = WPI/MoDi. Therefore, in the studied system oil droplet coalescence during drying increases when the elastic behavior of the interfacial film decreases. Practical applications: Spray drying of emulsions is a widely used process in the food industry for production of, for example, infant formula, dairy powders, and encapsulated aroma and coloring compounds. The oil droplet size in the resulting powder determines sensory aspects and stability of the final product. This study deepens the understanding of the changes in oil droplet size occurring during spray drying as affected by the formulation components, allowing therefore a better control of the quality of spray dried food emulsions. [ABSTRACT FROM AUTHOR]

Ultrasound assisted spray drying has been extensively used in the food and pharmaceutical industries for increasing the stability of variety of compounds involved in different applications, especially for drying sensitive compounds in the case of pharmaceutical industries. The use of ultrasonic spray drying has shown promising results in pharmaceutical sector though the application in food industries is still in the development stage possibly due to the absence of suitable designs, lower throughput values, and scale of operations. Considering these aspects, the current review focuses on the analysis of ultrasound-assisted spray drying for the food products and bioactive compounds so as to provide a better perception for the use in food processing industries. A detailed study into the diverse application of ultrasound in spray drying for encapsulation, microsphere generation, etc. in food industry and the enhancement into such applications using ultrasonic nozzle has been presented. Along with this, guidelines for the operating conditions involved in ultrasonic atomization for suitable applications with desired outputs and a detailed comparison with other nozzles have also been presented. Several advantages of ultrasonic spray drying over conventional method such as better size distribution, no nozzle clogging, lower velocity atomization, etc. have also been discussed. The low velocity spray generation using ultrasonic atomizers eliminates the requisite for large drying chambers thus, contributing to the compact designs. Overall, it has been clearly demonstrated that ultrasound offers lots of promise for improving the operations mainly with reduced processing times, enhanced production rates, and product quality. [ABSTRACT FROM AUTHOR]

Nowadays, there is a growing trend in the consumption of bioactive food ingredients and their use in the production of functional foods. Since these bioactive components are very sensitive to process and environmental conditions, and also to deliver them appropriately into our body, encapsulation technology has been emerged as a promising solution to achieve these goals. Spray drying is one of the most common and popular techniques for the encapsulation and drying of food ingredients. With the emergence of nanotechnology and its many benefits, scientists have focused on the development of nano-based materials and techniques in the food industry. Bioactive ingredients loaded in nanoparticles and nanocarriers could be applied as helpful nano delivery systems for the production of functional foods and nutraceutical delivery systems. The problem with conventional spray drying is the limited possibility of obtaining powder nanoparticles as the cyclone separating units can not result in collecting those very small particles. Nano spray dryer has been designed successfully to address this issue. This article will focus on the fundamentals of a nano spray drying system and its applications in the food industry. The scientific findings so far confirm that the nano spray dryer technology has been well-practiced in the drying and encapsulation of different food ingredients such as vitamins and minerals, phenolic compounds, carotenoids, and essential oils and fatty acids, although it is still at the beginning. It is possible to produce powder nanoparticles with a uniform size distribution through the ultrasonic atomizer in this system and electrostatic separation unit. A very small volume of sample is needed for this instrument which is a big advantage for expensive raw ingredients. The main challenge is that there is no possibility to conduct pilot or industrial scale experiments with this nano spray dryer system for the commercialization of the relevant products that could be available in the coming years. Image 1 • Spray drying is one of the most common techniques for encapsulation of food ingredients. • The problem with conventional spray drying is limited possibility of obtaining nanoparticles. • Nano spray dryer has been designed successfully to produce powder nanoparticles. • The main challenge is no possibility of pilot/industrial-scale experiments with this system. [ABSTRACT FROM AUTHOR]

Microparticles embedded with cellulose nanofibers (CNFs) are produced via spray drying. The microdroplets are created in the spray dryer by atomization. The solvent evaporates from the droplet, and the dried particles are formed. The drying kinetics on the scale of one droplet is still not well understood. Drying of a single droplet CNF suspension was investigated in an acoustic levitator. The drying kinetics and morphology evolution during the drying process were obtained. The reaction engineering approach (REA) model provided a reasonable prediction of the drying kinetics. An absolute relative error of 2.5 % between the measured initial mass of the droplet and the REA model's estimated value was reported. [ABSTRACT FROM AUTHOR]

This paper reviews experimental works on the effects of single nozzle location and multi-nozzle atomization on the mechanism of particle agglomeration in spray drying. In addition to the naturally occurring primary agglomeration, forced and secondary agglomeration is observed as an effect of different nozzle positions or multiple-nozzle atomization in spray drying. Particle size diameters in the spray drying process for atomization from a single nozzle located at the top of the tower are larger than at the bottom of the tower because of the lower ambient air temperatures and longer residence time in the agglomeration zone. The trend of reduction in particle size is observed in all analyzed works when the nozzle is moved down towards the air inlet, due to droplets' exposure to higher air temperatures and shorter residence time in the drying chamber. Conditions of droplet–droplet, dry–dry or sticky–dry collisions leading to the development of coalescence, agglomeration and rebound zones for multiple-nozzle atomization are described and discussed. Typically, log normal PSD was found for single-nozzle spraying whereas for multi nozzle arrangement, bi-modal particle size distribution was found both for drying in lab and industrial scale. [ABSTRACT FROM AUTHOR]

Inhalable metal organic framework (MOF) aerosols have been developed via spray drying as a therapy for multi-drug resistant (MDR) tuberculosis (TB). The CuPOA2 (pyrazinoate acid) MOFs can be tailored to exhibit a respirable mass median aerodynamic diameter (MMAD) of 2.6 μm. This method is repeated to manufacture Gd0.1Cu0.9(POA)2 MOFs for inhalable theragnostics. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the possibility of obtaining a juçara pulp powder by spray drying with no carrier agent addition. The pulp was filtered and then dried in a lab scale spray dryer. The process yield was relatively high (66%) and a highly anthocyanin-rich (7,079 ± 83 mg/100 g cyanidin-3-glucoside) powder was obtained. Total phenolic content (14,305 ± 551 mg/100 g) and antioxidant capacity (4,155 ± 92 µmol of Trolox/g) were satisfactorily preserved after drying, showing similar or better results than those reported using carrier agents, as well as solubility, bulk density and morphology. Finally, pulp powder was stable for 103 days, at different storage conditions, with respect to color, anthocyanin content and antioxidant capacity, showing potential to be used as a natural colorant or antioxidant in food products. [ABSTRACT FROM AUTHOR]

The thermal degradation of fresh skim milk, reconstituted skim milk and two model systems with different lactose/WPI ratios in a new design of spray dryer has been investigated. The extent of thermal degradation has been measured by the formation of Advanced Maillard reaction products, as assessed by a fluorometric method. Significant changes have been found when the inlet temperature increased from 180°C to 190°C, suggesting that temperature may play an important role in the kinetics of milk degradation in spray dryers. The non‐uniform distribution of particle residence time in the pilot‐scale dryer suggested that the design and operation of the spray dryer used for drying may also affect the extent of thermally induced reactions during the spray‐drying process. Results from the spray drying of model systems with different lactose/WPI ratios suggested that WPI concentration may be the rate‐limiting factor. Colourimetric analysis of the samples suggested a strong correlation between the formation of advanced Maillard reaction products and the color intensities of the spray‐dried products. Practical Applications: A correlation exists between the color intensity of the spray‐dried products and formation of advanced Maillard reaction products, which can be potentially further developed as a rapid, cost‐effective quality evaluation method for spray‐dried products. The discussion of the effect of spray drying conditions on the wall‐deposition and re‐entrainment process and thus the particle residence time distribution may also assist in improving the spray‐drying process for thermally sensitive products. [ABSTRACT FROM AUTHOR]

Increased awareness by industry of greenhouse gas (GHG) emissions is forcing companies to examine electrical technologies as alternatives to fossil fuel‐driven thermal ones. Spray drying of milk is recognized as a high‐energy process and is of particular importance to New Zealand. It requires inlet air temperatures higher than most existing electrically‐driven heat‐pumps can reliably achieve. Already some companies internationally are considering freezing and shipping milk concentrates rather than drying which begs the question as to whether the GHG emissions of frozen concentrate outweigh the GHG avoided by not drying. This research note assesses the relative GHG emissions and indicates a GHG advantage for frozen concentrate shipping. Practical applications: Increased awareness of the significance of greenhouse gas (GHG) emissions is forcing companies to examine alternatives to fossil fuel‐driven thermal technologies. Spray drying of milk is recognized as a high‐energy process and is of particular importance to New Zealand. It requires inlet air temperatures higher than most existing electrically‐driven heat‐pumps can achieve and so commonly requires fossil‐fuel use. Already some companies internationally are considering freezing and shipping milk concentrates rather than shipping dried milk. This research note assesses the relative GHG emissions of conventional (fossil‐fuelled) processes, and a novel process involving frozen concentrate. The evaluation shows that significant greenhouse gas reduction is possible by shipping frozen concentrate. [ABSTRACT FROM AUTHOR]

Absorption enhancers are often a major component of solid oral peptide formulations as compared to the active pharmaceutical ingredient and excipients. This commonly results in poor tabletability that is hard to mitigate in direct compaction by addition of small amounts of excipients. To improve the tabletability of bulky absorption enhancers, the model absorption enhancers, sodium cholate and deoxycholic acid, were co–spray-dried with hydroxypropyl methylcellulose E5, where the percentage of absorption enhancers was not lower than 90% (w/w). The physicochemical properties of the resulting powders were assessed by laser diffraction, scanning electron microscopy, X-ray powder diffraction, thermogravimetric analysis, and differential scanning calorimetry. The powders were compressed into tablets, and the tabletability was evaluated. Co–spray drying with 10% of hydroxypropyl methylcellulose significantly improved the tabletability of the both absorption enhancers. Moreover, it was demonstrated that small particle size and amorphous state rather than high moisture content contributed to the improved tabletability of the spray-dried powders. The study suggests that spray drying technology can be promising to overcome the poor tabletability of oral peptide formulation consisting of large amounts of absorption enhancers. [ABSTRACT FROM AUTHOR]

A continuous challenge for spray drying operations is the optimal control of product quality despite the complex process removal of water and particle formation. In general, high product functionality (e.g. in terms of reconstitution behavior, high enzyme activity or appropriate living probiotic bacteria) is key to the success of spray-dried powders. In this article, we review scientific studies that employ single droplet drying approaches to unravel underlying phenomena of spray drying process. Moreover, we identify scientific challenges to advance single droplet drying studies and thus contribute to development of mechanism-based guidelines for spray drying of functional food powders. [ABSTRACT FROM AUTHOR]

Myrtle (Eugenia gracílima Kiaersk) is a fruit that has significant amounts of anthocyanins and its sensory characteristics give it commercial value and its short shelf life justifies studies on conservation processes. The aim of this study was to assess the dehydration of myrtle pulp in spray dryer using maltodextrin as promoter, evaluating the effect of drying temperatures of 150, 170, and 190 °C on the powder obtained. Increasing the drying temperature provided lower moisture content, water activity and anthocyanin values and total color difference. Acidity and insolubility of powders were better for lower drying temperatures. In general, there were changes in the shape of powder particles by increasing the drying temperature and different collection locations on the spray dryer. The model that best fit experimental data of adsorption isotherms at 25 °C was Peleg. Isotherms were classified as type III. [ABSTRACT FROM AUTHOR]

Lyotropic liquid crystals (LLCs) are interesting wall-materials for encapsulation technology, in which monoacylglycerols (MAGs) are considered as potential ingredient for LLC formulation. This study, therefore, applied palm oil-based MAGs to encapsulate Gac fruit oils and compared the effect of two drying methods (freeze-drying and spray-drying) on the quality of products during storage. Wall-materials were prepared by ultrasound dispersing MAGs/water mixtures (40/60, w/w) into Pluronic solution (2%, w/w) to formulate LLC dispersions. Then, Gac fruit oils were encapsulated by freeze-drying and spray-drying. Various technologies were applied to characterize the properties of dispersions, the encapsulated powder morphology and the loading capacity. Obtained results showed that LLC dispersions made of palm oilbased MAG were micro- and nano-emulsions which were very convenient for encapsulating Gac fruit oils. For both drying methods, β-carotene of Gac fruit oils was successfully entrapped by MAGs with a high loading capacity (200 μg β-carotene/g powder). The degradation of encapsulated β-carotene after four storage weeks was 10 - 40% and freeze-dried samples showed a better protection effect in comparison to spray-dried samples. [ABSTRACT FROM AUTHOR]

This study evaluated the physical-chemical properties and structure of cellulose nanocrystals (CNC) produced from pine cellulose pulp, and dried by two different methods: Spray-Drying (SD) or Freeze-Drying (FD). After drying, CNC were characterized in terms of size, z-potential, elemental analysis, conductometric titration, crystallinity and thermogravimetry. Complementary, analysis by force microscopy, dynamic sorption and infrared spectroscopy were carried out. Results showed that different drying methods did not produce significant differences in zeta potential, crystallinity and degradation temperature. However, CNC dried by FD showed smaller size but higher aspect ratio, and higher sulfur content, which would explain the significant higher sorption observed in CNC-FD at relative humidity higher than 80%. Drying method does not influence the formation or modification of cellulose bonds as FTIR suggested. Our study suggests that how CNC is dried will influence the CNC's structure and will modify some of their physico-chemical properties. This information is relevant since it can be used as an input for the scale-up processing of CNC and would define the performance in some of their technological applications. [Display omitted] • Drying method produced cellulose nanocrystals (CNC) with different aspect ratio. • Drying method defines the sulfur content in CNC. • Sulfur content and CNC's structure modify the moisture sorption mainly at high relative humidity. • Physico-chemical properties such as charge, crystallinity and degradation temperature were not affected by the drying method. [ABSTRACT FROM AUTHOR]

O objetivo do trabalho foi avaliar o potencial do soro de leite líquido como agente encapsulante de Bifidobacterium Bb-12 por spray drying, comparando-o com a goma arábica, a qual é tradicionalmente utilizada na tecnologia de microencapsulação. Foram determinados o rendimento da microencapsulação e a viabilidade das microcápsulas durante o armazenamento. Quando o soro de leite foi utilizado como agente encapsulante, o rendimento da microencapsulação foi maior e a viabilidade das células manteve-se elevada e constante durante doze semanas. O soro de leite apresentou-se como um eficiente agente encapsulante de Bifidobacterium por spray drying.The objective of this study was to evaluate the potential of liquid whey as the encapsulating agent Bifidobacterium Bb-12 by spray drying, compared with arabic gum, which is typically used in microencapsulation technology. The microencapsulation yield and viability during storage were determined. When the whey was used as the encapsulating agent, the microencapsulation yield was higher, and cell viability remained high and steady for twelve weeks. The whey was shown to be an effective encapsulating agent of Bifidobacterium by spray drying.

Aloe mucilages of Aloe ferox (A. ferox) and Aloe vera (A. vera) were spray-dried (SD) at 150, 160 and 170 °C. Polysaccharide composition, total phenolic compounds (TPC), antioxidant capacity and functional properties (FP) were determined. A. ferox polysaccharides were comprised mainly of mannose, accounting for >70% of SD aloe mucilages; similar results were observed for A. vera. Further, an acetylated mannan with a degree of acetylation >90% was detected in A. ferox by 1H NMR and FTIR. SD increased the TPC as well as the antioxidant capacity of A. ferox measured by both ABTS and DPPH methods, in particular by ~30%, ~28% and ~35%, respectively, whereas in A. vera, the antioxidant capacity measured by ABTS was reduced (>20%) as a consequence of SD. Further, FP, such as swelling, increased around 25% when A. ferox was spray-dried at 160 °C, while water retention and fat adsorption capacities exhibited lower values when the drying temperature increased. The occurrence of an acetylated mannan with a high degree of acetylation, together with the enhanced antioxidant capacity, suggests that SD A. ferox could be a valuable alternative raw material for the development of new functional food ingredients based on Aloe plants. [ABSTRACT FROM AUTHOR]

[Display omitted] Amino acids (AAs) have been used as excipients in protein formulations both in solid and liquid state products due to their stabilizing effect. However, the mechanisms by which they can stabilize a protein have not been fully elucidated yet. The purpose of this study was to investigate the effect of AAs with distinct physicochemical properties on the stability of a model protein (lysozyme, LZM) during the spray-drying process and subsequent storage. Molecular descriptor based multivariate data analysis was used to select distinct AAs from the group of 20 natural AAs. Then, LZM and the five selected AAs (1:1 wt ratio) were spray-dried (SD). The solid form, residual moisture content (RMC), hygroscopicity, morphology, secondary/tertiary structure and enzymatic activity of LZM were evaluated before and after storage under 40 °C/75 % RH for 30 days. Arginine (Arg), leucine (Leu), glycine (Gly), tryptophan (Trp), aspartic acid (Asp) were selected because of their distinct properties by using principal component analysis (PCA). The SD LZM powders containing Arg, Trp, or Asp were amorphous, while SD LZM powders containing Leu or Gly were crystalline. Recrystallization of Arg, Trp, Asp and polymorph transition of Gly were observed after the storage under accelerated conditions. The morphologies of the SD particles vary upon the different AAs formulated with LZM, implying different drying kinetics of the five model systems. A tertiary structural change of LZM was observed in the SD powder containing Arg, while a decrease in the enzymatic activity of LZM was observed in the powders containing Arg or Asp after the storage. This can be attributed to the extremely basic and acidic conditions that Arg and Asp create, respectively. This study suggests that when AAs are used as stabilizers instead of traditional disaccharides, not only do classic vitrification theory and water replacement theory play a role, but the microenvironmental pH conditions created by basic or acidic AAs in the starting solution or during the storage of solid matter are also crucial for the stability of SD protein products. [ABSTRACT FROM AUTHOR]

Abstract Rapeseed and honeydew honey were spray dried by dehumidified air, with NUTRIOSE® as a drying carrier, to create a product with prebiotic properties, in line with current "clean label" trend. Because of the low inlet air humidity, drying temperature was decreased (inlet/outlet: 75/50 °C). Such an approach gave the possibility to reduce the amount of added carrier. Thus, honey powders containing 80% of honey solids were produced and characterized. Drying was performed with very high powder recovery (84.4–93.9%), especially in the variants containing 80% of honey solids. Although there were some differences in the physical properties between powders produced by the application of dehumidified air and by the traditional spray drying (but containing the same ratio of honey to carrier), the overall properties were comparable: low water content (below 2.5%) and low water activity (below 0.2), medium or high cohesiveness, high hygroscopicity (above 20%), bed porosity between 50 and 70%. [ABSTRACT FROM AUTHOR]

To shorten the duration of upper respiratory tract (URT) diseases or reduce the symptoms alternative treatments to antibiotics and decongestants are needed, due to their side effects and frequent failure. Recent human microbiome research has led to the hypothesis that beneficial bacteria, capable of colonizing the human URT, could constitute an interesting approach to prevent and reduce URT diseases. Since probiotics are live microorganisms with a beneficial effect on the host, it is important that the probiotic bacteria are delivered at the site of action, without hampering their viability. Here, the formulation applicability of eight new probiotic candidates belonging to the Lactobacillus genus was evaluated after spray drying. Besides viability, growth and fermentation abilities after drying were confirmed through experiments. A promising strain was chosen for further optimization. Microscopic visualization and flow cytometry of bacterial morphology identified spray drying as a suitable processing method. Adhesion experiments indicated no changes in functionality. Lastly, the contact time between bacteria and hot drying air was identified as a crucial parameter in spray drying of probiotics. [ABSTRACT FROM AUTHOR]

Purpose: Spray drying plays an important role in the pharmaceutical industry for product development of sensitive bio-pharmaceutical formulations. Process design, implementation and optimisation require in-depth knowledge of process-product interactions. Here, an integrated approach for the rapid, early-stage spray drying process development of trehalose and glucagon on lab-scale is presented. Methods: Single droplet drying experiments were used to investigate the particle formation process. Process implementation was supported using in-line process analytical technology within a data acquisition framework recording temperature, humidity, pressure and feed rate. During process implementation, off-line product characterisation provided additional information on key product properties related to residual moisture, solid state structure, particle size/morphology and peptide fibrillation/degradation. Results: A psychrometric process model allowed the identification of feasible operating conditions for spray drying trehalose, achieving high yields of up to 84.67%, and significantly reduced levels of residual moisture and particle agglomeration compared to product obtained during non-optimal drying. The process was further translated to produce powders of glucagon and glucagon-trehalose formulations with yields of >83.24%. Extensive peptide aggregation or degradation was not observed. Conclusions: The presented data-driven process development concept can be applied to address future isolation problems on lab-scale and facilitate a systematic implementation of spray drying for the manufacturing of sensitive bio-pharmaceutical formulations. [ABSTRACT FROM AUTHOR]

This study aimed to develop a simulation model for the kinetics of Maillard reactions during the spray-drying process of model systems. Two different modeling approaches were used: lumped-parameter and distributed-parameter models. The reaction kinetic model was developed by fitting experiment results from iso-thermal heating experiments with different model systems at various temperatures and moisture contents with Arrhenius-type equations. The developed reaction kinetic models were coupled with drying kinetics and segregation models adopted from previous studies. The prediction results from the models developed were then compared with those from spray-drying experiments, and both modeling approaches showed a reasonable agreement with the experimental data. The distributed parameters modeling approach showed a 17.7% improvement in sum of square errors compared to the traditional lumped-distributed modeling approach. Practical Applications Two different mathematical models with different approaches were developed and have shown reasonable performance in predicting the kinetics of Maillard reactions in spray drying. The models developed in this study can be used to improve the spray-drying process of thermally sensitive products where Maillard reaction or other types of thermal degradation may occur. [ABSTRACT FROM AUTHOR]

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The spray dryer is very often applied in chemical and food - processing industries. This drying method includes suspension - spraying with the contents about 30 to 65% of dried substance. The drying period in most cases is only several seconds. The drying agent is the warm air. A model of momentum, heat and mass transfer in the atomization - swirler zone was proposed. To verify the model an extensive experimental investigation was performed on water evaporation at different initial air temperatures, feed rates, flow rates of the drying agent and different parameters of atomization and initial particle size distribution. Good agreement between experimental results and theoretical data was achieved. The model was verified experimentally on the basis of results of investigations on drying of a 40% mass solution of starch and water.

Spent coffee grounds (SCG) are a coproduct that causes environmental impacts worldwide. Thus, consciously reusing the SCG is an eminent need. This work aimed to encapsulate phenolic compounds and antioxidants obtained from SCG extracts through spray‐ and freeze‐drying techniques using different isolated and combined wall materials. The dried powders produced were evaluated for moisture content, water activity, bulk density, hygroscopicity, color, content of phenolic compounds and antioxidants, and the results were compared. The results showed that all evaluated treatments resulted in a powdered product with low values of bulk density, moisture and water activity, especially for freeze‐drying. The freeze‐dried product also showed higher hygroscopicity. Regarding the content of phenolic compounds and antioxidants, both drying methods showed high levels of these compounds in the dried product and good encapsulation efficiency, reaching 83.43%. In most cases, spray‐drying and freeze‐drying did not differ statistically (p > 0.05) in relation to bioactive compound content and encapsulation efficiency. In relation to wall materials, albumin showed the worst performance in the retention of bioactive compounds. On the other hand, pure gum arabic combined with maltodextrin led to better preservation of these compounds. Practical Application: Spent coffee grounds are a coproduct generated in large quantities in the world. The encapsulation of phenolic and antioxidant compounds protects and enables their application in different food matrices. Therefore, the evaluation of different encapsulation methods and wall materials is important to define good process conditions. [ABSTRACT FROM AUTHOR]

In this analytical study, spray drying of detergent particles of diameters 0.4-1 mm by using counter-current air heated at around 300oC is investigated using Matlab©. Particle drying using hot gases is a mature process with a vast variety of applications ranging from dried food to powdered detergent production. The study shows a strong relationship between the drying process (final water content) and particle size, drying gas temperature, as well as the tower dimensions since cross-sectional area of the tower has a direct control on vertical gas velocity, thus heat and mass transfer coefficients while the height of tower is closely related to residence time of particles in tower which guarantees the targeted drying level. The conclusions of this study can be a guide to have a better set of drying parameters such as inlet temperatures and humidity/water content as well as exit temperatures and humidity/water content and valuable information on how these relate to heat energy consumption necessary to heat the air from atmospheric conditions to the desired drying gas temperature. It is also worth indicating that the measurement of the absolute humidity in tower exhaust is a good parameter to control the drying process in an effective way. [ABSTRACT FROM AUTHOR]

The incorporation of bioactive nutrient compounds such as vitamins into food systems can provide a simple way to develop new functional foods. In this work, the controlled release of two vitamins (vitamins B12and C), microencapsulated by a spray-drying process, is studied. With a properly designed controlled-release system, the compounds are released at the desired site and time, and at a desired rate. The main kinetic release models are applied and discussed. Also, the main mechanisms associated to the release were identified. The use of models to predict in vivo bio-performance is an advantage in the development of new products. [ABSTRACT FROM PUBLISHER]