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Whey is a very perishable food and a potent source of protein. It might be more commercialized through the process of spray drying, which would enhance its shelf life. No CFD computational models applied to the drying of fresh sweet whey have been reported in the literature to investigate transport phenomena in spray dryers and to predict crucial design parameters such as deposition, powder recovery, and drying efficiency. Using an Eulerian-Langragean technique, the behavior of multiphase flow as well as heat and mass transfer were investigated. The influence of the inlet air temperature was evaluated in relation to the velocity profiles of the continuous and discrete phases, the residence time distribution, the particle diameter formed, the air temperature near the injection zone, the particle temperature, and the mass fraction of evaporated water. Furthermore, performance parameters such as powder recovery, particle deposition, and drying efficiency were projected for varied air inlet temperatures. The velocity, residence time, and particle size distribution patterns were similar for the different air inlet temperatures. Greater variations might be noticed in the injection zone, especially in the temperature and mass fraction profiles. The lowest drying temperature resulted in the lowest particle deposition and the best thermal efficiency, making it the optimal process condition. This investigation can serve as a benchmark for the design of optimized spray dryers with greater thermal efficiency and yield to produce powdered whey.

The application of low-temperature, dehumidified air-assisted spray drying was evaluated as a method to produce carrier-free powders of selected sugar-rich and acid-rich food materials: blackcurrant juice concentrate, mango puree, purple carrot juice concentrate, sauerkraut juice, kiwiberry pulp, and tomato pulp. As a consequence of decreased drying air humidity, inlet/outlet air temperature was lowered to 80/55°C. In order to validate this new approach, the conventional spray drying was conducted as well at 180/80°C inlet/outlet air temperature. The powder recovery, physical properties and color parameters of powders were determined. For blackcurrant juice concentrate, mango puree, purple carrot juice concentrate and sauerkraut juice it was possible to obtain carrier-free powders only by low-temperature drying, while for kiwiberry pulp and tomato pulp both variants of spray drying were effective. Decreased drying temperature positively influenced some properties of powders; i.e. , median particle size diameter and hygroscopicity of the powders obtained by spray drying with dehumidified air were lower compared to those of the powders dried by conventional spray drying. Carrier-free powders of some raw materials (blackcurrant juice concentrate, mango puree, purple carrot juice concentrate, sauerkraut juice) were spray dried solely with dehumidified air, underlining its importance in the production of "clean label" products.

The application of low-temperature, dehumidified air-assisted spray drying was evaluated as a method to produce carrierfree powders of selected sugar-rich and acid-rich food materials: blackcurrant juice concentrate, mango puree, purple carrot juice concentrate, sauerkraut juice, kiwiberry pulp, and tomato pulp. As a consequence of decreased drying air humidity, inlet/outlet air temperature was lowered to 80/55°C. In order to validate this new approach, the conventional spray drying was conducted as well at 180/80°C inlet/outlet air temperature. The powder recovery, physical properties and color parameters of powders were determined. For blackcurrant juice concentrate, mango puree, purple carrot juice concentrate and sauerkraut juice it was possible to obtain carrier-free powders only by low-temperature drying, while for kiwiberry pulp and tomato pulp both variants of spray drying were effective. Decreased drying temperature positively influenced some properties of powders; i.e., median particle size diameter and hygroscopicity of the powders obtained by spray drying with dehumidified air were lower compared to those of the powders dried by conventional spray drying. Carrier-free powders of some raw materials (blackcurrant juice concentrate, mango puree, purple carrot juice concentrate, sauerkraut juice) were spray dried solely with dehumidified air, underlining its importance in the production of "clean label" products. [ABSTRACT FROM AUTHOR]

This paper discusses the physicochemical properties of powders obtained by spray drying of cloudy beetroot juice, using dehumidified air in variants with or without carriers. The inlet air temperature was 130 °C or 90 °C, and the addition of the carriers was at a ratio of juice to carrier solids of 3:2. In the obtained powders, the following physicochemical properties were determined: water content and water activity, apparent density, loose and tapped density, porosity, flowability, particle size and morphology, and the content and retention of betalains. It was possible to dry cloudy beetroot juice without the use of carriers at low temperatures (90 or 130 °C). The 100% beetroot powders were characterized by satisfactory physicochemical properties, often better than those with carriers (including lower hygroscopicity and higher color saturation and yield). A lower loss of betalains was found for the powders with the addition of carriers. The best process yields were obtained for the powder without carriers at 130 °C and 90 °C. [ABSTRACT FROM AUTHOR]

BACKGROUND Apple concentrate and honey were spray‐dried with traditional carriers (maltodextrin, Nutriose®, Kleptose®) and with skimmed milk powder as a carrier substitute offering added value for the final product. RESULTS: Skimmed milk powder, although having the lowest glass transition temperature, was the best carrier in terms of the highest powder recovery (higher than 80% was achieved) and with powder physical properties comparable to those obtained with other carriers. Thus, skimmed milk powder was used to produce honey powder of reduced carrier content (to 25% solids). The physical properties of the powders obtained and lower powder recovery indicated more problematic drying of AC. Powders produced with skimmed milk were characterized by enhanced nutritional value compared with variants with traditional carriers. CONCLUSION: Thus, skimmed milk is proposed as a natural carrier for spray‐drying, offering high processing yield, the possibility to reduce carrier content in honey powder, and to create products of nutritional added value. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This paper discusses the physicochemical properties of powders obtained by spray drying of cloudy beetroot juice, using dehumidified air in variants with or without carriers. The inlet air temperature was 130 °C or 90 °C, and the addition of the carriers was at a ratio of juice to carrier solids of 3:2. In the obtained powders, the following physicochemical properties were determined: water content and water activity, apparent density, loose and tapped density, porosity, flowability, particle size and morphology, and the content and retention of betalains. It was possible to dry cloudy beetroot juice without the use of carriers at low temperatures (90 or 130 °C). The 100% beetroot powders were characterized by satisfactory physicochemical properties, often better than those with carriers (including lower hygroscopicity and higher color saturation and yield). A lower loss of betalains was found for the powders with the addition of carriers. The best process yields were obtained for the powder without carriers at 130 °C and 90 °C.

The aim of the work was to obtain and characterize powdered honey containing substantially higher amount of honey than was reported in literature before. For this purpose, dehumidified air was applied as a drying medium during spray drying at low temperature (inlet/outlet air temperature: 75/50 °C). This method gave the possibility to reduce carrier content in the final product. Apart from maltodextrin, used traditionally as drying carrier, NUTRIOSE characterized by prebiotic properties was also tested, to produce added-value honey powder. Drying parameters were adjusted compared to traditional high temperature spray drying to perform the process at high drying rate and yield (powder recovery). By using dehumidified air as the drying agent honey powders containing 80% of honey solids were obtained, with a yield above 80%. Both these values were higher than noted ever before in the case of honey spray drying. The physical properties of powders were typical for spray dried materials, although increased honey content resulted in increased hygroscopicity. Even though NUTRIOSE has a higher potential as a health promoting ingredient, compared to maltodextrin, it had lower potential as a drying carrier (powders had higher water activity and hygroscopicity). [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]

The effect of heat treatment (75 °C) and spray drying with the addition of Arabic gum (inlet/outlet air temperature 180/75 °C), on the diastase activity of multifloral honey (MH) and rape honey (RH) was investigated. The physical properties of the powders (particle size and morphology, water content and activity, bulk loose and tapped density, angle of repose, hygroscopicity) directly after drying and after 12 weeks of storage were studied. During heat treatment, diastase activity decreased gradually, to decline below limit values after 180 min. Diastase activity in the powders was lower than in fresh honeys, but it was concluded that temperature was not the only factor affecting this decrease. Powders were characterized by low water content and medium flowability, which was improved after storage due to particle size increase. Diastase activity in powders was stable during storage. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the powder recovery, color characteristics, glass transition temperature (Tg), and sticky point (Ts) temperature of spray-dried pomegranate juice powder as affected by different concentrations of maltodextrin (DE 20). Five different combinations of pomegranate juice and maltodextrin (95:5, 90:10, 85:15, 80:20 and 75:25 v/w) were prepared and spray dried in a laboratory-type spray dryer. Increase in concentration of maltodextrin significantly increased the powder recovery and 20% of maltodextrin was required for successful spray drying of pomegranate juice (powder recovery > 50%). Color values of pomegranate juice powder were significantly influenced by concentration of maltodextrin. With increase in concentration of maltodextrin powder, lightness (L* value) increased from 45.54 to 74.46, a* value decreased from 20.43 to 11.45 and b* value decreased from 2.16 to −3.83. Results showed that with increase in maltodextrin concentration from 5% to 25%, Tg increased from 38.23°C to 71.61°C. Sticky point temperature also showed an increase from 56.86 to 89.43°C with increase in concentration of maltodextrin.

The potential of maltodextrin (DE 20) and soya protein isolate (SPI) in spray drying of tamarind pulp was compared. Powder recovery was zero when the tamarind pulp was spray dried alone. A greater amount of maltodextrin (MD; 55%) was required for successful spray drying of tamarind pulp, whereas a small amount of SPI (20%) was needed for the same purpose. The study revealed that the mechanism for the increase in product recovery with the addition of MD is due to the increase in overall glass transition temperature of tamarind pulp powder. However, using SPI, preferential migration of the protein to the surface of droplets/particles resulting in the formation of a glassy skin was responsible for a reduction in stickiness between the particles and dryer wall and hence increased the powder recovery. The potential of SPI in reducing powder hygroscopicity was almost comparable to that of MD, confirming its efficiency as a drying aid. Tamarind pulp powders produced with SPI had a larger particle size with a wrinkled particle surface morphology and high flowability compared to powders produced with MD. The study showed the excellent potential of SPI as a drying aid in production of quality tamarind pulp powder. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the effect of adding soya protein isolate (SPI) as a complementary drying aid of maltodextrin (MD) on spray drying of tamarind pulp. Tamarind pulp powders were prepared by spray drying of tamarind pulp, adding 0, 5, 10, 15, and 20% of SPI together with maltodextrin as the drying aids. The results showed that the addition of SPI resulted in a significant increase in powder recovery from 9.35 to 70.04%, thereby reducing the requirement of higher levels of maltodextrin for the production of quality tamarind pulp powder. The powders were evaluated for moisture content, bulk density, particle size, morphological characteristics, cohesiveness, and glass transition temperature. With the addition of SPI in the feed material, the powder samples showed a significant variation in their properties. Addition of SPI decreased the cohesion index of the powders from 14.21 to 9.29 mm, thereby increasing the flowability of the powders. Surface morphology of the powders showed that the addition of SPI resulted in an indented and wrinkled particle surface, a characteristic feature of powders produced with protein as the drying aid. [ABSTRACT FROM PUBLISHER]

• Recrystallization of α occurs during PBF-EB part recovery and hot isostatic pressing. • Widmanstätten α / β at the surface recrystallizes to globular α / β. • Globular surface layer thickness increases with increasing blasting intensity. • This globular surface may be present for all net-shape PBF-EB Ti-6Al-4V parts after HIP. A globular α recrystallization has been discovered at the surface of net shape electron beam powder-bed fusion (PBF-EB) Ti-6Al-4V alloy parts. This recrystallization is the result of powder recovery blasting followed by hot isostatic pressing treatment (HIP), which mimics the thermomechanical treatment necessary to achieve globularization in wrought Ti-6Al-4V. The thickness of the globular surface α is variable depending on the blasting intensity as well as the presence of surface protrusions that block the line-of-sight of the blasting media. The globular layer contains a 0001 orientation relationship parallel to the blasting direction, plus a low intragranular orientation deviation, when compared to the bulk. The results indicate that this globular α at the surface may be present for all net-shape Ti-6Al-4V components that have been manufactured via PBF-EB and subjected to a HIP treatment. Tunable fatigue and wear performance may be possible through controlled blasting parameters and globular surface layer thickness. [ABSTRACT FROM AUTHOR]

Seedless barberry is one of the most popular native fruits in Iran. Conventionally, barberry fruit is dried and consumed as ornamental additive in traditional food. Barberry fruit juice contains high anthocyanins, therefore its spray dried powder can be used as good sources of anthocyanins. Maltodextrin(MD)-Arabic gum(AG) mixture, as carrier in various ratios, were added to the extract to prepare spray dried powder. The drying inlet air temperatures were 160°C and 180°C with air flow rate set to 50 m³/h. The anthocyanins content, product recovery, color, moisture content, dissolution, water activity, and density of spray-dried barberry powder were measured. The results revealed that the product recovery was about 78% when the air temperature set to 160°C and the barberry extract was supplemented with 75:25 ratio of MD:AG. The optimum amount of anthocyanins (390.46 mg/100g) in powder was achieved when the inlet air temperature was 160°C and equal proportions of MD:AG added to the feed. Powder loose and tapped bulk density increased from 0.179 to 0.310 and 0.380 to 0.570 g/cm3 respectively, as level of MD in the ratio increased from 7.5 to 15 g/100 ml. SEM micrographs of the powder indicate an increasing trend in particle size as result of increase of concentration of MD as drying aid. The data obtained in the present work may be used to prepare spray dried barberry extract in a commercial scale. [ABSTRACT FROM AUTHOR]

The aim of this work was to spray dry honey (rape and buckwheat varieties) with Arabic gum ( AG) as a carrier alone or in combination with sodium caseinate (1% and 2% w/w NaCas) as a drying aid. Powder recovery ranged from 66.2 ± 0.7% to 75.8 ± 4.9%, and the values were significantly higher for samples containing NaCas. Powders were characterised by good flowability, the addition of NaCas had positive impact on this factor. However, the hygroscopicity of protein-containing powders was higher, especially at 2% w/w of NaCas. Powders hygroscopicity was related to particle size: AG powder of the smallest particle size was the most hygroscopic, while the particle size did not affected flowability, which was strongly related to the feed solution composition. Based on the obtained results, it was concluded that the addition of 1% w/w of NaCas as a drying aid during buckwheat and rape honey spray drying with Arabic gum as a carrier is favourable, while the further increase of protein content does not give additional benefits. [ABSTRACT FROM AUTHOR]

The aim of this work was to compare the efficiency of different carrier agents (maltodextrin, gum arabic, starch sodium octenyl succinate, whey protein concentrate, and egg albumin) on the powder recovery and physicochemical properties of persimmon powders produced by spray drying. Moisture content, water activity, hygroscopicity, solubility index, total phenol retention, color parameters, particle size, morphology, crystalline state, and sorption isotherms of persimmon powders were determined. No powder was recovered when the persimmon pulp was spray dried alone. The amount of maltodextrin, gum arabic, starch sodium octenyl succinate, whey protein concentrate, and egg albumin needed to obtain a powder recovery of 70% was 45, 30, 30, 25, and 10%, respectively. The use of maltodextrin, gum arabic, and starch sodium octenyl succinate resulted in higher total polyphenol retention and better reconstitution properties, but the powders were paler than those with whey protein concentrate and egg albumin. All carriers could aid the formation of persimmon irregular spherical microcapsules. However, powders produced with maltodextrin and gum arabic had a smoother surface and a more spherical shape than powders produced with other carriers. In addition, powders produced with starch sodium octenyl succinate, whey protein concentrate, and egg albumin were more agglomerated and shriveled compared to those produced with maltodextrin and gum arabic. All experimental data of water adsorption were well fitted to the Guggenheim-Anderson-de Boer (GAB) model. [ABSTRACT FROM AUTHOR]

Standard electron beam powder-bed fusion Ti-6Al-4V powder recovery and hot-isostatic pressing has been found to result in a surface layer microstructure change to globular α / β. Thickness control of this surface layer up to 15 μ m was demonstrated by varying powder recovery blasting working distance and duration. This surface globular layer was found to improve high-cycle rotating bending fatigue strength at 10 7 cycles by 60 MPa for specimens with smooth surfaces. The same trend was not observed for specimens with as-built surface roughness because globularization did not occur at dominant fatigue crack initiation sites; the roots of deep surface crevices. • Globular recrystallization on the surface of Ti-6Al-4V after PRS followed by HIP. • Globular surface thickness controlled by varying blasting working distance/duration. • Thicker globular surface layer leads to higher fatigue strength. • No globular phase at root of deep as-built surface notches. [ABSTRACT FROM AUTHOR]

Concentrated lime juice with 20% total soluble solids was dried using three levels of maltodextrin (40%, 50%, and 60% solid base) and a BÜCHI B-190 spray dryer. The drying air temperature and flow rate were 140 °C, 155 °C, and 170 °C and 47.1, 53.5, and 57.8 m/h, respectively. A total of 27 experiments were conducted (in triplicate) with the feed rate, temperature, and compressed air flow for the atomizer kept constant. Analysis of the data revealed that product recovery increased when the maltodextrin in the feed and drying air flow rate were increased, but the inlet air temperature had no significant ( P < 0.05) effect on powder recovery. The moisture content of the powder varied with the maltodextrin level, inlet air temperature, and air flow rate. Using scanning electron microscope images, larger particle size was observed with the increase of maltodextrin concentration. Powder bulk density also increased from 0.41 to 0.68 g/cm, depending on the level of maltodextrin, whereas the drying air temperature and flow rate were not as effective. The results of this study are beneficial for scaling up the spray drying of lime juice to the food industry. [ABSTRACT FROM AUTHOR]

Abstract: The development of surface stickiness of droplets of sugar and acid-rich foods during spray drying can be explained using the notion of glass transition temperature (T g). In this work, criteria for a safe drying regime have been developed and their physical basis provided. A dimensionless time (ψ) is introduced as an indicator of spray dryability and it is correlated with the recovery of powders in practical spray drying. Droplets with initial diameters of 120 μm were subjected to simulated spray drying conditions and their safe drying regime and ψ values generated. The model predicted the recovery in a pilot scale spray dryer reasonably well. [Copyright &y& Elsevier]

Taking Chongqing Maanshan artificial aggregate processing system as the example, we analyzed the application of power recovery equipment used in the artificial processing system. It shows that the recovery equipment effect is good after nearly four years of operation. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the powder recovery, color characteristics, glass transition temperature (Tg), and sticky point (Ts) temperature of spray-dried pomegranate juice powder as affected by different concentrations of maltodextrin (DE 20). Five different combinations of pomegranate juice and maltodextrin (95:5, 90:10, 85:15, 80:20 and 75:25 v/w) were prepared and spray dried in a laboratory-type spray dryer. Increase in concentration of maltodextrin significantly increased the powder recovery and 20% of maltodextrin was required for successful spray drying of pomegranate juice (powder recovery > 50%). Color values of pomegranate juice powder were significantly influenced by concentration of maltodextrin. With increase in concentration of maltodextrin powder, lightness (L* value) increased from 45.54 to 74.46, a* value decreased from 20.43 to 11.45 and b*value decreased from 2.16 to −3.83. Results showed that with increase in maltodextrin concentration from 5% to 25%, Tgincreased from 38.23°C to 71.61°C. Sticky point temperature also showed an increase from 56.86 to 89.43°C with increase in concentration of maltodextrin. [ABSTRACT FROM AUTHOR]