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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]

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]

Karkade calyces' samples (variety Rahad) collected from different local sites were spray dried, and the powder samples were analyzed physically, chemically and microbiologically. The particle size of the various karkade powder samples ranged from 11.8 to 14.1 μm, while the flowability (angle of repose) ranged from 41° to 43° 20'. The reconstitution properties slightly varied when the various karkade samples were compared. The ranges of wettability, sinkability and dispersibility were 320-370 s, 800-850 s and 0.04-0.05 OD, respectively. The bulk density ranged from 0.57 to 0.65 g/ml, and the yield of karkade powder of the various samples ranged between 31.4 and 34.3%. The spray-dried samples from different sites were comparable in most of the chemical components, and they contained relatively good amount of macro- and micronutrients and high nutritive value. Virtually, all the spray-dried karkade powder samples were devoid of coliform, staphylococci and Salmonella cells. [ABSTRACT FROM AUTHOR]

In this study, new smoothies were formulated based on low fat milk and barberry concentrate, and their physicochemical and bioactive properties were investigated. Physicochemical parameters of functional smoothie powders were obtained by applying low and high temperature drying methods, and by a combination of procedures programmed to process smoothie powders. The effect of spray drying (SP), refractance window (RW), foam mat drying (FM), spouted bed drying (SB) and a combination of spouted bed drying were studied herein, while the infrared lamp system (SBIR) shows how these methods affect the smoothie's physical properties (such as bulk density, porosity, color) and its chemical properties (such as total anthocyanin content and antioxidant capacity measured by the DPPH method). The study also proved that an increase in the speed of rotation from 10 rpm to 100 rpm would lead to a diminished apparent viscosity from 642.39 mPas to 381.98 mPas regarding all reconstituted dried powders, which thus verifies their shear thinning behavior. The work highlighted that this new approach to combining the drying methods for the production of functional smoothie powders at an inlet temperature of 80 °C can result in the best maintenance of antioxidant activity (11.67 %) with the least moisture content (3.19 %). [ABSTRACT FROM AUTHOR]

A scaling-up approach from drying of a thin layer wet material in a experimental tunnel to a pilot scale spray drying was developed through determining drying kinetics of quick evaporation process. Maltodextin was selected as solid material in solution to be dried. Critical moisture contents as a function of initial water evaporation rate (drying rate) shows that there is the same variation between the small scale test tunnel and the pilot scale spray dryer. Result of CFD modelling demonstrates that drying kinetics obtained from the small-scale tunnel could be properly applied to scale-up the spray drying process. [ABSTRACT FROM AUTHOR]

Toona sinensis, whose young leaves and shoots are edible and nutritious, is a perennial deciduous tree vegetable. In this paper, the volatile constituents of dehydrated fresh young leaves of Toona sinensis obtained by different drying methods were micro-extracted in solid-phase, and then analyzed with gas chromatography-mass spectrometry (GC-MS). The major flavor components include caryophyllene, aromadendrene, nonadecane, and phytol. Comparing with convection oven drying and natural solar drying, vacuum drying and microwave drying can preserve most of the original flavors of Toona sinensis. [ABSTRACT FROM AUTHOR]

This work investigates the effect of different drying processes on chemical, nutritional and leaves colour characteristics for Ilex paraguariensis leaves. These processes were composed of typical drying techniques (roasting + rotary dryer and roasting + conveyor dryer), and cutting-edge techniques (microwave oven [MW], freeze-drying (FD) and oven dryer [OD]). The MW can be an alternative technique, this is because the content of phenolic compounds (77 mg/g), antioxidant capacity (DPPH and ABTS) (∼370 and ∼1040 μM TE/g), methylxanthines and caffeoylquinic acids (2–4 mg/g) were similar, and sometimes higher, to the conventional drying processes. Leaves dried with MW also exhibited satisfactory nutritional analysis for protein (16.4%), dietary fibre (52.3%), ash (6.4%), lipid (6.1%) and moisture (5.7%), implying that yerba mate is a potential source of fibre and protein. Furthermore, the MW preserved leaves green colour (high and low scores of b* and a*, respectively). [ABSTRACT FROM AUTHOR]

Carrot peel generated from the juice factories is considered as waste and it can be potential for further recovery of carotenoids. Drying treatment is essential to minimise degradation of carotenoids and ease transportation as well as storage of the peel for further processing. This study aimed to determine the impact of different drying conditions on its physicochemical and antioxidant properties to propose the most suitable conditions for drying carrot peel for further recovery of carotenoids. Drying conditions were found to significantly affect retention of total carotenoids, β-carotene, lutein and lycopene as well as antioxidant capacity in carrot peel. Optimal conditions for hot-air drying were at 40 °C for 3.5 h; vacuum drying were at 60 °C, −60 kPa for 4 h; dehumidification drying was at 50 °C for 2.5 h with relative humidity (RH) of 16–21 %; and microwave drying was at 600 W for 7 min. In comparison with freeze drying (control) and other three different drying methods at each optimal conditions, dehumidification drying at 50 °C with RH of 16–21 % was the most effective method as it retained high levels of total carotenoids (2.75 mg/g DW), β-carotene (1.57 mg/g DW), lutein (0.17 mg/g DW) and lycopene (0.78 mg/g DW). Dried carrot peel also had potent antioxidant properties (ABTS: 4.71 and CUPRAC: 19 mM TE/g DW). Therefore, these conditions are recommended for drying carrot peel for further recovery of carotenoids. [ABSTRACT FROM AUTHOR]

This work investigated the agglomeration of native cornstarch and production of microcapsules by dripping of sodium alginate suspensions into calcium chloride solution. The crosslinking reaction formed a calcium alginate that worked as an encapsulation matrix and coated the cornstarch granules. The spherical beads produced were rigid and compact, and resistant to mechanical handling. The differential scanning calorimetry (DSC) computed the thermal resistance of the cornstarch-alginate beads. Particles containing 50 % w/w calcium alginate showed an increased gelatinization peak compared to particles with a higher starch content. The increase in alginate fraction resulted in beads with a higher particle density. Scanning electron micrographs showed the coating of cornstarch by the calcium alginate matrix. The beads were compact and with no superficial pores. DSC thermograms of native cornstarch showed a gelatinization temperature of 70.0 °C, and the gelatinization range was 64.6-80.4 °C, while beads containing 50 % alginate had an increased peak at 79.5 °C and the gelatinization interval was 71.0-90.2 °C. When compared with the native cornstarch, cornstarch-alginate beads had a lower water absorption, and the gelatinization occurred at a higher temperature and over a wider temperature range. [ABSTRACT FROM AUTHOR]

Gac fruit (Momordica cochinchinensis L.) pulp is high in carotenoids and fiber; however, it is discarded during process. Both maturity stages of matured gac fruit could be used in the drying experiments. Gac fruit pulp was dried by different drying methods including tray drying (40-60 °C), heat pump-assisted dehumidified drying (40-60 °C), microwave drying (450-900W), mixed-mode solar drying and freeze drying. The Modified Henderson model presented the best fit of desorption isotherms. New model proposed was the best drying model. Quality evaluation by β-carotene, lycopene, lutein, total phenolics and antioxidant activity revealed that heat pump-assisted dehumidified drying at 60 °C provided the highest lutein, total phenolics and antioxidant activity and could reduce drying time by 25% and increased lutein, total phenolics and antioxidant activity by 12.6%, 32.0% and 0.3%, respectively and is more promising drying method for gac fruit pulp. [ABSTRACT FROM AUTHOR]

In China, there are about 1.6 million tons of thinned young apples (TYAs) every year after blossoming and fruit thinning. These resulting fruits, in reality, could be utilized as agricultural and food resource. This study was undertaken to evaluate the influence on physical properties, bioactive attributes of TYAs that were subjected to chosen drying techniques. In general, significant differences ( p < 0.05) exist in physical appearance and polyphenol. Antioxidant capacity was also investigated on the basis of assay for Trolox equivalent antioxidant capacity (TEAC) by 2,2ʹ-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), reducing power and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging ability. Judging from the results, it was concluded that hot air drying at 60℃ is appropriate for large-scale production; furthermore, vacuum freeze drying tends to manufacture high-value up-market TYA products that are available to give the best results for dehydrated fruits. It is suggested that TYA has great potential in the food industry as functional ingredient. [ABSTRACT FROM AUTHOR]

Dragon fruit ( Hylocereus polyrhizus) peel is high in antioxidants and fiber; however, it is discarded during processing. In this study, changes in physico-chemical properties of dragon fruit peel after drum drying were determined. Ground dragon fruit peel was drum dried at 1 rpm with 2 bar steam pressure, then analyzed for physical, chemical and functional properties. The betacyanin content was twofold higher in drum-dried powder (41.55 mg/g dm) than in a fresh sample (80.21 mg/g dm), yet up to 98.62% of the total phenolic content was retained with a 3.328 mg trolox/g dm reduction in the radical scavenging activity. The density of the powder was 0.1315 g/mL with 51.44% soluble in water. The functional properties determined included water holding capacity (2.523 g water/g sample), oil holding capacity (3.565 g oil/g sample) and swelling capacity (6.233 mL/g). The results of this study indicate that drum-dried dragon fruit peel can be considered to contain potentially functional ingredients. [ABSTRACT FROM AUTHOR]

The Box-Behnken design of experiments under response surface methodology (RSM) was used to optimize the foaming process for the development of foam mat-dried muskmelon powder. The independent variables were the concentration of egg albumen (EA), carboxymethyl cellulose (CMC) and whipping time (WT). The responses were foam density, foam drainage volume and foam expansion. The optimum conditions for foaming process were EA (11.59% w/w), CMC (0.59% w/w) and WT (3.97 min). The unfoamed muskmelon pulp took longer time to dry to the final moisture content of 2% d.b than foamed pulp. The effective diffusivity for the foamed muskmelon pulp was found to be higher than the unfoamed pulp. The unfoamed pulp resulted in a sticky and dark colored powder, whereas the foamed pulp had a free-flowing and light colored powder. The flaky and porous foam-dried product can be used as an ingredient in broad range of food products. [ABSTRACT FROM AUTHOR]

The increasing interest in the antioxidant activity of lycopene has been to promote the consumption of tomato and tomato-based products. The aim of this work was to evaluate tomato ( Lycopersicon esculentum Mill) drying in thin layer through response surface methodology. The independent variables investigated in this study were drying air temperature (60, 70 and 80°C) and wet sample thickness (3, 5 and 7 mm). The drying condition with the lower colour value (Hue angle) and higher lycopene content was 60°C and sample thickness of 3 mm. In this condition, the responses for the colour (Hue angle) and lycopene content values were 47.7 0.2° and 301.9 3.1 μg g-, respectively. The lycopene loss was similar to that reported in the literature (30-50%) using more expensive methods of tomato drying such as freeze-drying and lyophilization. [ABSTRACT FROM AUTHOR]1, respectively. The lycopene loss was similar to that reported in the literature (30-50%) using more expensive methods of tomato drying such as freeze-drying and lyophilization. [ABSTRACT FROM AUTHOR]

The technique of in-chamber blending in practice has been investigated, by altering the configuration of a Buchi B290 small-scale spray dryer having a two-fluid nozzle, through adding an extra pipe into the chamber to agglomerate maltodextrin (DE18) particles with 20% salt solution sprayed through the atomizer. Scanning Electron Micrographs showed the importance of splash impacts between salt droplets and maltodextrin particles in this geometry, suggesting that the collision efficiency is strongly affected by whether or not the salt droplets completely surround the dry maltodextrin particles. Changing the air inlet temperature did not affect the measured amount of collisions (from Atomic Absorption Spectroscopy) significantly, but both the main air and the nozzle air flow rates had significant effects on the collision outcomes. [ABSTRACT FROM AUTHOR]

The article discusses the manuscripts included in the issue from the Asia-Pacific Drying Conference, which took place from August 12, 2008 to August 14, 2008. [ABSTRACT FROM AUTHOR]