Powder Yield Research Articles

Optimization of Spray Drying Parameters and Wall Material Composition of Juniper (Juniperus drupacea L.) Extract Using Response Surface Methodology

The aim of this study was to produce a juniper extract powder rich in some bioactive and volatile components such as phenolics, α-pinene and d-limonene with a high yield. For this purpose, the juniper extract, which can be used in various food formulations, was spray-dried under optimized conditions. In this optimization, inlet air temperature (120°C - 180°C) in the spray drying process and the carrier composition were selected as independent variables, while dependent variables included drying efficiency and the total phenolic (TPC), and α-pinene contents of the extract powder. Response surface methodology was used to maximize product yield, TPC and volatile levels, especially α-pinene. The optimum inlet air temperature and carrier ratio were 180ºC and 15 g gum Arabic (GA) per 100 mL extract, respectively. The highest powder yield (37.92%), TPC (9.91 mg GAE/g dm powder) and α-pinene content (peak area 1.3×107) were obtained under the optimum conditions while the bulk and compressed bulk densities, TPC and antioxidant activity of the extract powder were 0.39±0.01 g/cm3 and 0.51±0.02 g/cm3, 9.89±0.27 g gallic acid equivalent (GAE)/100 g (dm) and 4.12±0.14 g Trolox® equivalent antioxidant activity (TEAC)/100 g dm, respectively. The particle size of the powder produced under optimum conditions ranged from 1.09 to 22.39 µm. Fifteen volatiles in both juniper extract and the reconstituted form of the extract powder were identified, and the major components of juniper extract were d-limonene, α-pinene and γ-muurolene.

Production of a herbal drink by spray drying of mixed purple basil extract-lemon juice; formulation, process optimization, and characterization

This article focuses on the production of an herbal drink containing the mixture of basil extract and lemon juice (65:35 (% v/v)), at inlet air temperature (IAT) (110–190 °C) as well as the concentrations of maltodextrin (MD, 0–7.5%) and gum Arabic (GA, 0–7.5%). Response surface methodology (RSM) was employed to investigate the variation of spray-dried powder attributes including moisture content (MC), water activity, water solubility, product yield, particle size, total monomeric anthocyanins (TMA), and aroma components. The optimum conditions for maximizing encapsulation efficiency and powder yield were IAT of 146 °C, 9.68% MD, and 5.32% GA. Both IAT and MD/GA ratio had a significant effect on final powder properties except for water activity. The GC-MS data revealed that the predominant aroma components in the final powder, lemon juice, and the reconstituted product were limonene and γ-terpinene; limonene; γ-terpinene, linalool, and 1.8 cineole, respectively. The results demonstrated that spray drying (SD) using GA/MD blends improved the consolidation of bioactive compounds in powdered form.

An Investigation of the Metal Powder Ultrasound Atomisation Process of 316L Stainless Steel.

This paper presents the results of a study on the atomisation process of 316L material. The primary objective of the study was to obtain the highest quality, quantity and yield of 316L metal powder for the established atomisation parameters (torch current and wire feed speed) at the assumed process time. Using experiment planning according to the Taguchi method, 16 pairs of controllable variable parameters were developed. It was observed that the low current high-wire speed configuration resulted in the formation of a considerable amount of molten metal on the sonotrode platform. This phenomenon prevented the ultrasound system from working properly, so some of the processes were interrupted. The results obtained from the tests showed that torch current and wire feed speed are parameters that have a significant impact on the efficiency of the ultrasonic atomisation process. The highest efficiency was achieved by the process with a torch current of 100 A and a wire feed speed of 9 mm/s.

Rekayasa Proses Pembuatan Serbuk Minuman Tradisional dari Rempah dan Non-Dairy Creamer melalui Foam Mat Drying

Spice drinks are traditional beverages made from ginger and lemongrass, with the addition of vegetable creamer to enhance their quality. This study aimed to determine the effect of varying the ratio of spices to vegetable creamer on the organoleptic and physicochemical characteristics of the drink. Additionally, it sought to evaluate the yield, antioxidant activity, specific heat, and mass balance of the spice drink powder from the selected formulation. The experimental design was a Completely Randomized Design with two factors: the percentage ratio of spices to vegetable creamer. The results showed that varying the spices to vegetable creamer ratio significantly affected the organoleptic characteristics, particularly hedonic and hedonic quality attributes. Regarding physicochemical properties, the ratio of spices significantly affected color, dissolution time, total soluble solids, pH, and moisture content. The ratio of vegetable creamer significantly influenced color lightness, dissolution time, pH, and moisture content. The best treatment was the A3B1, which resulted in a yield of 18.09%, exhibited an antioxidant activity of 73.5%, had a specific heat of 1.5361kJ/kgoC, and showed an efficiency value of not more than 1 (100%). The most significant mass loss occurred during washing, amounting to 216,21 g or 65,63% of the incoming raw material.

Investigation of the Effect of Milling Time on Elemental Powders of Oxi‐Reduction Nickel and Hydrogenation–Dehydrogenation Titanium

Mechanical alloying (MA) is widely applied in the synthesis of blended elemental or prealloyed powders. This work evaluates the effect of milling time on elemental nickel and titanium powders produced by oxi‐reduction and the hydrogenation–dehydrogenation process, respectively. The powders are characterized by scanning electron microscopy, X‐ray diffraction, particle size, powder yield, and differential scanning calorimetry. It is observed that increasing the milling time promotes the formation of a structure composed of thin lamellae of nickel and titanium, which results in the beneficial effect of lowering the temperature for the formation of the intermetallic of the Ni–Ti system and in the powder yield achieved. The reduction of milling time in the MA process of NiTi alloys enhances technological efficiency by decreasing their overall processing time.

Modeling the interaction between powder particles and laser heat sources

This study investigates the spheroidization of titanium Ti-6Al-4V powder particles using numerical models developed in Abaqus and OpenFOAM. Spherical particles are crucial in powder-based additive manufacturing due to their superior flowability, packing density, and mechanical properties, enhancing printing precision and the quality of final products. While conventional techniques such as gas atomization and plasma spheroidization have been extensively researched, the potential of laser spheroidization remains underexplored. To address this gap, detailed numerical analyses of laser spheroidization were conducted, modeling heat transfer from the laser to powder particles using a transient uncoupled heat transfer method with latent heat considerations, while particle deformation was simulated with a phase-fraction-based interface-capturing approach integrated with Navier-Stokes equations. The results, validated against analytical models, indicate that particles within the 20–80 μm range experience optimal spheroidization within a 0.005-second residence time under laser heating, with particles smaller than 30 μm reaching evaporation temperatures of 5,000°C, while larger particles reshape without evaporating under a typical heat flux of 94 MW/m2 (1.8 kW laser power). This study demonstrates that laser spheroidization of Ti-6Al-4V powder can potentially increase powder yield by 10%, offering higher power density and shorter melting times compared to plasma spheroidization, thus presenting a more efficient alternative for achieving spherical particles of specific sizes.

Effect of Ti/Ta ratio on the microstructure and mechanical properties of Hf20Mo15Nb25Ta20-xTi20+x refractory high-entropy alloys

The limited deformation capacity at room temperature remains a significant challenge in refractory high-entropy alloys (RHEAs). In this study, the fine-grained Hf20Mo15Nb25Ta20-xTi20+x (x = 0, 5, 10, 15) alloys were prepared by mechanical alloying and subsequent spark plasma sintering (SPS), based on precise component regulation. The impact of altering the Ti/Ta ratio (R, R = (20+x)/(20-x)) on the pre-alloyed powders and the as-sintered alloys were investigated. An increase in R-value led to larger powder particle sizes and lower powder yields, which was attributed to the improvement in the plasticity of the pre-alloyed powders. After SPS sintering, the as-sintered alloys were comprised of two BCC solid solution matrices and nanoscale precipitated phases. As the R-value increases, the stability of the microstructure decreases slightly, while the yield strength shows a slight improvement, and the plastic strain experiences a relatively significant enhancement. The as-sintered Hf20Mo15Nb25Ta20-xTi20+x alloys all exhibited an excellent balance of strength and plasticity. Theoretical calculations revealed that the yield strength of the alloys was the result of the combined effect of several strengthening mechanisms, predominantly substitutional solid solution strengthening. Furthermore, a systematic discussion was conducted on the reasons for the improvement in the plasticity of the as-sintered alloys. This study presents an effective approach to enhancing the room temperature deformation capacity of RHEAs, thereby facilitating their broader application.

Spray Drying of Inca Peanut Meal Protein Hydrolysate to Produce Protein Powder Drink Mix

The optimal conditions (maltodextrin concentration and inlet air temperature) for spray drying Inca peanut meal protein hydrolysate (IMPH) were determined. The maltodextrin concentration was varied at 5, 10 and 15 % by weight, and inlet air temperature was varied at 150, 160 and 170 °C. The IMPH was subjected to spray drying, where the feed solution was atomized into fine droplets and exposed to a hot air stream, leading to rapid drying and the formation of powder. The moisture, protein, yield, water activity and water solubility index (WSI) of IMPH powder were analyzed. The optimal condition for spray drying IMPH powder utilized 10 % maltodextrin and an inlet air temperature of 160 °C. Under these conditions, the moisture, protein, yield and WSI of IMPH powder were 2.93, 36.93, 38.95 and 99.59 %, respectively, while water activity was 0.41. IMPH powder particles were spherical and non-agglomerate. Inca peanut meal protein powder drink mix (IMPD) with cocoa flavor was the most acceptable. The IMPD with cocoa flavor could be promoted as a high protein and high dietary fiber product. It could be kept at 35 ± 2 °C for 12 weeks, whilst retaining good microbiological properties. HIGHLIGHTS The optimal conditions for spray drying Inca peanut meal protein hydrolysate (IMPH) were determined to be 10% maltodextrin and an inlet air temperature of 160 °C. This resulted in high yield, protein content, and water solubility, while keeping moisture and water activity low. IMPH powder had spherical, non-agglomerated particles, and cocoa-flavored Inca peanut protein powder drink mix (IMPD) was the most preferred in sensory evaluations. The IMPD with cocoa flavor was identified as a high-protein, high-dietary-fiber product, suitable for storage at 35 °C for up to 12 weeks while maintaining good microbiological quality. The study highlights the nutritional benefits of the cocoa-flavored IMPD, which includes essential amino acids, omega-3 fatty acids, and antioxidant properties. GRAPHICAL ABSTRACT

Luminescence Properties of Cs<sub>3</sub>Cu<sub>2</sub>I<sub>5</sub> Phosphors Powder with Solid State Method

The low-temperature solid-state method is utilized to prepare Cs3Cu2I5 phosphors powder by using the cesium iodide (CsI) and cuprous iodide (CuI) as the raw materials. The phase structures of samples were investigated by using X-ray spectrum and steady-state fluorescence spectrometer. The experimental results show that all of samples were crystallized in the orthorhombic structure with pnma space group at the annealing temperature of 100-400°C. Cs3Cu2I5 phosphors exhibits a strong blue photoluminescence emission with peak at 440nm under excitation at 310nm. With the increase of the annealing temperature in the range of 100-400°C, the photoluminescence quantum yield (PLQY) of Cs3Cu2I5 powder achieved the 79.95%. It is revealed that the prepared Cs3Cu2I5 powder phosphors potentially have the promising application in the blue light emitting materials.

Star-shaped multifunctional organic emitters based on N-(2-cyanophenyl) carbazole frameworks: Effects of steric hindrance fluorene and heavy-atom bromine

To investigate the effects of steric hindrance fluorene and heavy-atom bromine on the general optoelectronic properties of star-shaped organic emitters based on 9-(2-cyanophenyl) carbazole (OCzPhCN) frameworks, heavy element of bromine and steric hindrance fluorene were introduced into OCzPhCN to produce four derivatives of 2-(3-bromo-9H-carbazol-9-yl)benzonitrile (BrCzPhCN), 2-(3-bromo-6-(9-(4-ethoxyphenyl)-9H-fluoren-9-yl)-9H-carbazol-9-yl)benzonitrile (BrFCzPhCN), 2-(3-(9-(4-ethoxyphenyl)-9H-fluoren-9-yl)-9H-carbazol-9-yl)benzonitrile (FCzPhCN) and 2-(3,6-bis(9-(4-ethoxyphenyl)-9H-fluoren-9-yl)-9H-carbazol-9-yl)benzonitrile (2FCzPhCN). The fluorene units obviously improve the thermal stability of the obtained compounds, and 2FCzPhCN has the highest thermal stability with 5 % mass heat loss temperature reaching 447 °C. In different polar solvents, the absorption peaks wavelength of OCzPhCN, FCzPhCN and 2FCzPhCN are basically unchanged, and the redshifted emission peaks are positively correlated with solvent polarity. The photoluminescence quantum yields (PLQYs) of OCzPhCN, BrCzPhCN, FCzPhCN, BrFCzPhCN and 2FCzPhCN powders were 20.17 %, 5.43 %, 30.75 %, 3.27 % and 23.56 %. The fluorescence and phosphorescent quantum efficiencies of OCzPhCN, BrCzPhCN, FCzPhCN, BrFCzPhCN and 2FCzPhCN powders are 9.76 % and 10.41 %, 1.2 % and 3.23 %, 28.45 % and 2.3 %, 3.27 % and 0 %, 23.56 % and 0 %. OCzPhCN, BrCzPhCN and FCzPhCN powders show obvious room temperature phosphorescent emission, and the phosphorescent emission lifetime of OCzPhCN, BrCzPhCN and FCzPhCN powders at 561 nm, 576 nm and 568 nm are 193.17 ms, 18.65 ms and 7.25 ms. Compared with OCzPhCN, the introduction of bromine decreases the PLQY and the phosphorescent lifetime of BrCzPhCN powder, while the fluorescence quantum efficiency of the compound FCzPhCN powder has been improved. The corresponding single-triplet energy splitting (ΔEST) of OCzPhCN, FCzPhCN and 2FCzPhCN in solutions are 0.49 eV, 0.63 eV and 0.63 eV, and the corresponding ΔEST values of OCzPhCN, BrCzPhCN FCzPhCN powders are 1.19 eV, 0.74 eV and 0.55 eV. The steric hindrance fluorene units result in smaller and stabilized ΔEST in the solid powder states, and the same situation is opposite in the unimolecular solutions. The maximum external quantum efficiency of organic light-emitting diode based on 10,10′-(4,4′-sulfonylbis (4,1-phenylene)) bis (9,9-dimethyl-9,10-dihydroacridine) hosted by OCzPhCN reaches 12.7 %, and the external quantum efficiency at 100 cd/m2 rolls down to 11 %. OCzPhCN is the best emitters in terms of room temperature phosphorescent emission and host applications.

RETRACTED ARTICLE: Starch Recovery Process from the Tiger Nut Horchata Processing Waste

AbstractTiger nut horchata solid residue (HSR) has high starch content (about 23%, dry basis) that can be recovered to valorise this waste, together with other valuable components, such as oil, fibres, or phenolic compounds. In this study, a chemical-free, sustainable process was proposed to obtain starch with good yield and purity. This consists of a high-speed homogenisation step with distilled water, followed by filtration and phase separation by density in the slurry to obtain a starch-rich sediment that can be isolated by decantation. Five minutes of homogenisation at 10,200 rpm allows for obtaining 14.5 g of starch powder per 100 g of dried HSR, with a purity of about 85% and WI of 94.97. Applying 1 washing cycle to the filtering residue increased the starch powder yield up to 17 g/100 dried HSR, without notable losses in starch purity, whereas centrifugation at 15,000 g for 1 h in the phase separation step highly reduced separation time, increasing starch purity up to 92%. Thus, it was possible to recover up to 70% of the starch present in the HSR. The obtained starch had similar morphological characteristics, crystallinity degree, and gelatinisation behaviour to that present in the tiger nut tubers, exhibiting similar thermal stability to that reported for other native starches. Therefore, HSR can be used as a starch source for different uses.

Innovative utilization of olive mill wastewater phenolics extracted by lecithin: spray-dried powders in cake formulations

In the present study, the olive mill wastewater (OMW) phenolics were extracted with soy lecithin using the cloud point extraction method, and this enriched lecithin (OMW-L) was converted into spray-dried powders using maltodextrin (MD) and whey protein concentrate to be utilized as a dry food ingredient in a cake premix. The inlet temperature of 170 °C and a 3 mL/min feed flow rate yielded the highest powder yield (70.88 ± 2.12%) with a moisture content of 3.78 ± 0.03% when the mass ratio of lecithin to MD was 1:3 (w:w). The hydroxytyrosol and tyrosol contents of the powder were 42.60 ± 4.51 mg/100 g and 15.48 ± 2.50 mg/100 g, respectively. Vanillic acid, caffeic acid, 3-hydroxybenzoic acid, catechin, and rutin were also identified in the powders. The spray-dried OMW-L powder with a higher loading of polyphenols was then used in a cake premix, replacing 1% and 3% of wheat flour. This substitution significantly reduced the K value of the cake batter, as determined by rheological analyses. The addition of spray-dried OMW-L powder to the cake samples, particularly at higher concentrations (3%), influenced both crust and crumb color, causing changes in L*, a*, and b* values. The hardness values of the cake samples did not alter when blank or OMW-enriched lecithin powders were added; rather, the hardness value was influenced by the powder content. Overall, this research offers a different perspective on the use of OMW phenolics in food applications, especially in ready-to-use blends, and demonstrates the effects of the obtained spray-dried lecithin powders on batter rheology and cake characteristics.Graphical abstract

Chia seed oil microencapsulated by spray-drying: optimization and microcapsules characteristics

A current trend in food research is the development of beneficial health products that could help to decrease certain risks of diseases. The chia seed (Salvia hispanica L.) oil is a proven source of essential fatty acids (omega-3), which can help to prevent cardiovascular diseases. In this study, chia seed oil was characterized and fatty acids were identified before and after the spray-drying process. A 32 factorial design with response surface methodology was utilized for chia seed oil spray drying experiments. Statistic design factors and levels were as follows: gum arabic: maltodextrin mixture (GA:MD) (1:1, 1:2 and 1:3 w/w) and drying temperatures (DT) (140, 160, and 180°C). A total of 67.9% of unsaturated fatty acids were found in raw chia seed oil and 65.7% in microencapsulated oil. The optimal parameters for the spray drying process were as follows: GA:MD 51:1 and DT, 180°C; powder yield rate, 49.5% (w/w), mean size of particles 129 µm, and sphericity coefficient of 0.11. Microcapsules tended to demean over time, changing their color, and producing agglomerate, which decreased their flowing capacity. On the other hand, the product was easier to handle, the oil was protected from heat and moisture conditions, and the microencapsulation process provided stability to the oil's active substances, such as omega-type fatty acids.

Application of Carboxymethyl Cellulose and Glycerol Monostearate as Binder Agents for Protein Powder Production from Honey Bee Brood Using Foam-Mat Drying Technique.

This study investigates the development of protein powder from honey bee drone broods using foam-mat drying, a scalable method suitable for community enterprises, as well as the preservation of bee broods as a food ingredient. Initially, honey bee broods were pre-treated by boiling and steaming, with steamed bee brood (S_BB) showing the highest protein content (44.71 g/100 g dry basis). A factorial design optimized the powder formulation through the foam-mat drying process, incorporating varying concentrations of S_BB, glycerol monostearate (GMS), and carboxymethyl cellulose (CMC). The physicochemical properties of the resulting powder, including yield, color spaces, water activity, solubility, protein content, and total amino acids, were evaluated. The results showed that foam-mat drying produced a stable protein powder. The binders (CMC and GMS) increased the powder's yield and lightness but negatively affected the hue angle (yellow-brown), protein content, and amino acid content. The optimal quantities of the three variables (S_BB, GMS, and CMC) were determined to be 30 g, 6 g, and 1.5 g, or 80%, 16%, and 4%, respectively. Under this formulation, the protein powder exhibited a protein content of 19.89 g/100 g. This research highlights the potential of bee brood protein powder as a sustainable and nutritious alternative protein source, enhancing food diversification and security.

Effect of Microscopic Properties on Flow Behavior of Industrial Cohesive Powder

The characteristics of powders on a bulk scale are heavily influenced by both the material properties and the size of their primary particles. Throughout the stages of storage and transportation in the powder processing industry, various forms of deformation and stress, such as pressure and shear, impact these materials. Recognizing the point at which a powder undergoes yielding becomes particularly significant in numerous applications. There are also times when the level of stress needed to maintain it must be understood. The measurement of powder yield and flow properties remains a challenge and is addressed in this study. As part of the European collaborative project, a number of shear experiments were performed using two shearing devices: the Schulze ring shearing device and the Anton Paar Powder Cell (APCC). These experiments have three purposes: (i) test reproducibility/consistency between two shear devices and test protocols; (ii) relate bulk behavior to microscopic particle properties, focusing on bulk density and thus the effect of cohesion between particles; and (iii) investigate the influence of the temperature of heated powders on the powder’s flow properties, which is important for industrial reactors. Interestingly, for samples with small particle sizes, bulk cohesion increases slightly, but bulk friction increases significantly because of particle interaction effects. The experimental data not only provide useful insight into the role of microscopically attractive van der Waals gravitational and/or compressive forces on the macroscopic flow behavior of bulk powders but also have industrial relevance. We also provide robust data of cohesive and attritional fine powder for silo design used for calibration and validation of silos, models, and computer simulations.

Objective texture evaluation of cosmetic sericite powders mixed with oil using constant-volume shear cell tester

Although sensory evaluation is often used to evaluate cosmetic powder textures, such evaluations are problematic because they are subjective and depend on human senses. Consequently, an objective evaluation is highly desired. We therefore report herein the use of a constant-volume shear tester to objectively evaluate the physical properties of a cosmetic powder. The goal of the study is to detect the differences in the physical properties of powders, which is done by applying a constant-volume shear test to oil-wet powders of differing textures mixed with dimethicone or squalane. Differences between dimethicone and squalane mixtures appear in the stress relaxation ratio (softness), the shear cohesion (moist feeling), the internal friction coefficient for friction (for normal stress of <10 kPa) between powder beds (smoothness), and the dynamic friction coefficient for friction between powder beds. Although the oils presented a similar degree of the powder yield locus, the shape of the powder yield locus indicates the state of the powder beds. The results of the study show that constant-volume shear testing can be used to objectively evaluate oil-wet powder textures.

Safflower protein as a potential plant protein powder: optimization of extraction and spray-drying process parameters and determination of physicochemical and functional properties.

The research about sustainable and alternative plant protein sources has accelerated with the increasing need for protein. Safflower meal has a potential to be used in protein production due to its high protein content. This research aimed to produce an alternative plant-based protein powder using safflower meal. Both extraction and spray-drying parameters of safflower protein powder production were optimized using response surface methodology to achieve maximum yield. Moreover, the physicochemical and functional properties of safflower protein were determined and compared with those of commercial protein powders (soy, sunflower, pea, fava bean, and rice). The optimum extraction conditions were found to be 33.06:1 mL-1 g solvent-to-meal ratio, pH 11.00, 23.34 °C extraction temperature, and 30.86 min extraction time, which were achieved with a protein yield response of 75.21%. The highest powder yield (51.28%) was recorded for drying conditions of inlet air temperature of 160.11 °C, aspiration rate of 54.17 m3 h-1, and feed flow rate of 16.01 mL min-1. According to the amino acid profile of safflower protein, the glutamic acid content (14 475 mg (100 g)-1) was highest, while the methionine content (96 mg (100 g)-1) was lowest. Moreover, safflower protein can be regarded as a high-quality protein due to its high essential amino acid ratio (41.55%). The experiments showed that safflower protein had high solubility and good foam and emulsifying properties. Safflower protein could be a nutritional and functional protein source for the food industry. © 2024 Society of Chemical Industry.

Impact of spray drying operating conditions on yield, secondary metabolites, antioxidant potential and storage quality of grape (Vitis vinifera L.) pomace powder

In the present investigation, spray drying independent operating conditions such as the inlet air temperature (A-IAT 130, 150 and 170 °C), outlet air temperature (B-OAT 60, 70 and 80 °C), needle speed (C-NS 3S, 4S, 5S), maltodextrin concentration (D-MD 10, 15, 20 %), pump speed (E-PS 5, 10, 15 mL/min) and water/grape pomace ratio (F-W/GP ratio 10, 15, 20) were optimized to develop the spray-dried grape pomace powder (SDGPP) with maximum yield. The impact of these conditions on total phenolic contents (TPC), total flavonoid contents (TFC), and antioxidant activity (DPPH· values) of SDGPP samples were analyzed. The independent spray drying factors (IAT, OAT, NS, MD, PS, and W/GP ratio) impart a strong direct effect (p ≤ 0.05) on powder yield, TPC, TFC, and DPPH· values. The interaction effects (A × B, A × C, A × D, A × E, A × F, B × C, B × D, B × E, B × F, C × D, C × E, C × F, D × E, D × F, and E × F) of independent variables were noted non-significant (p ≥ 0.05) for response values. After validation of the model and verification of results, the independents' variables were found in the range of 170 °C (IAT), 80 °C (OAT), 4S (NS), 15 % (MD), 10 mL/min (PS) and 15 (W/GP ratio) for yield (64.7 ± 1.18 %), TPC (7.66 ± 0.53 mg GAE/g), TFC (3.19 ± 0.30 mg CE/g) and DPPH· 140.3 ± 1.59 (100 µL/mL), respectively. The decrease in TPC, TFC, and DPPH· values of SDGPP samples was noted during 60 days of storage at 25 ± 2 °C and 65 ± 5 % RH (p ≤ 0.05) but not greater than unprocessed samples. It could be concluded that the protection of phenolic contents and retention of antioxidant activity of dried powders can be achieved at optimized spray drying conditions for discerning food and byproduct processing industries.

Performance of spray-dried Ziziphus jujuba extract using insoluble fraction of Persian gum-sodium alginate and whey protein: Microstructural and physicochemical attributes of micro- and nano-capsules.

The study focused on the impact of the insoluble fraction of Persian gum-sodium alginate and a blend of the insoluble fraction of Persian gum-sodium alginate (IFPG-Al) with whey protein isolate (WPI) on sprayed Ziziphus jujuba extract (JE) powder. The addition of whey protein led to powders with higher moisture (10%), higher solubility (99.19%), and lower powder yield (27.82%). The powders fabricated with WPI depicted the best protection of polyphenolic compounds (3933.4 mg/L) and the highest encapsulation efficiency activity (74.84%). Additionally, they had a higher T g (62.63°C), which indicates more stability of the powders during shelf life. The sphericity of the majority of the particles was noticeable in powders, but multi-sided concavities were visible in the protein-containing particles. Based on the particle size's results, IFPG-Al/WPI capsules fabricated relatively smaller particles (2.54 μm). It can be acknowledged that the presence of protein in particles can bring fruitful results by preserving valuable bioactive compounds.

Optimization of spray drying for lulo (Solanum quitoense Lam.) pulp using response surface methodology

Lulo (Solanum quitoense Lam.) is an exotic fruit with high potential in international markets due to its intense aromatic characteristics and its content of nutritional and bioactive compounds. However, it is highly perishable, which backslashes its potential for international exportation. Despite the drying processes affect the nutritional and sensory characteristics, fruit powders obtained by spray drying are promising products for the food, cosmetic, and pharmaceutical industries. This work was conducted aiming to optimize the spray-drying process of lulo pulp. A Box-Behnken design with response surface methodology was used, in which the factors evaluated were inlet air temperature (160 - 220 °C), maltodextrin concentration (15-35%), and whey protein concentration (WPC) (1-5% w/w). The feed rate and air velocity were kept constant at 4 mL/min and 9 m/s, respectively. The optimization resulted in an inlet air temperature of 205.6 °C, 35% maltodextrin, and 1.96% WPC. Under these conditions, the mathematical model estimated a powder yield of 62.8%, a moisture content of 2.3 %, a bulk density of 0.49 g/mL, a solubility of 91.9 %, and an ascorbic acid content of 120.8 mg/100 g powder. The optimal process conditions and the mixture of encapsulants (MD and WPC) allow for obtaining lulo powder with adequate yield and quality characteristics.