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Banana is one of the most important crops produced globally. It contains a wide variety of valuable compounds and has interesting functional properties. Moreover, many by-products and wastes are generated from its collection to its consumption. Bananas are highly perishable due to their high moisture content and an appropriate post-harvest technology and agricultural engineering would prolong its shelf life. Drying is an important and the widely used method of food processing. In addition, drying can also promote the development of value-added products. The quality of dried banana is highly dependent upon the drying method and conditions. Conventionally, bananas are sun- or hot-air-dried. However, these methods are often slow processes and the products obtained have poor quality, so other alternate drying technologies have been developed. This review focuses upon conventional and new drying technologies and pre-treatment methods. The hybrid drying techniques minimize the undesirable effects of drying on banana quality, improve the drying efficiency and provide superior quality products. [ABSTRACT FROM AUTHOR]

In aluminum-clad spent nuclear fuels, an (oxy)hydroxide layer on the surface of the cladding hosts chemisorbed water formed during reactor and post-discharge exposure to water. Any residual water is susceptible to generating hydrogen via radiolysis, which can be a risk associated with dry fuel storage. Engineering-scale forced helium dehydration (FHD) and vacuum drying tests were conducted on mock-up fuel assemblies that included corroded aluminum surrogate plates to assess the removal of bulk and chemisorbed water. Thermogravimetric analysis was performed on samples of the surrogate plates, both undried control samples used to determine onset temperatures associated with a phase change occurring in the oxide layer and samples from drying tests used to determine the effectiveness of each drying method. Both vacuum drying and FHD processes were capable of removing bulk water. However, FHD was determined to provide additional drying capabilities, including partial removal of chemisorbed water from bayerite due to the higher temperatures during drying. The temperature threshold for partial dehydroxylation of the oxide layer was determined to be around 220°C, meaning any drying methods attempting to remove chemisorbed water must exceed 220°C. [ABSTRACT FROM AUTHOR]

Copyright of China Condiment is the property of China Condiment and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A non-invasive capacitance instrument was embedded in the base of a vacuum-drying tray to monitor continuously the residual amount of solvent left in a pharmaceutical powder. Proof of concept was validated with Microcrystalline Cellulose laced with water, as well as water/acetone mixtures absorbed in a spray-dried Copovidone powder. To illustrate the role of impermeability of the base, we derive a model of vapor sorption that reveals the existence of a kinetic limit when solids are thinly spread, and a diffusion limit with greatly diminished effective diffusivity at large powder thickness. By monitoring the residual solvent content of powders, this new in situ technique offers advantages over indirect methods like mass spectrometry of vapor effluents, but without complications associated with probe fouling. To prescribe design guidelines and interpret signals, we model the electric field shed by the probe when a powder holds variable solvent mass fraction in the vertical direction. [ABSTRACT FROM AUTHOR]

A recently revised American Society for Testing and Materials consensus standard guide for drying of spent nuclear fuel (SNF) provides considerations and guidance for preparing SNF for its safe storage in a sealed dry storage system. The standard discusses (1) needs for drying, (2) techniques to dry, and (3) demonstration of adequate dryness. No specific approach is prescribed since the effective techniques and needs for drying depend on the specifics of the fuel and dry storage system. This paper discusses these topics using examples for both Zr-alloy-clad commercial SNF and for aluminum-alloy-clad research reactor SNF. Residual water can include free water (liquid and/or vapor), physisorbed water bound to internal surfaces, and chemisorbed water incorporated into surface films, such as (oxy)hydroxides. The potential impacts of these residual waters are corrosion/oxidation, radiolytic breakdown into gaseous and/or reactive species, and canister pressurization. For commercial SNF, inadvertent free water, even up to large amounts (e.g., 10+ mol), is not predicted to cause adverse corrosion degradation, except possible fuel oxidation for breached SNF. For aluminum-clad SNF, the production of radiolytic hydrogen with contribution from the chemisorbed water in its hydrated oxides is a primary consideration. For both SNF systems, canister pressurization is predicted to be well within the canister design, and flammability would not pose a safety concern using an oxygen limit of 5 vol % criterion. (Flammability control can be achieved by limiting either hydrogen or oxygen, and an oxygen limit is expected to be easier to meet in the presence of radiolytic H2 generation.) The two primary technologies for SNF drying, vacuum drying and forced-gas dehydration, are described herein, and drying tests and campaigns using these methods are cited. Dryness criteria and the methods used to detect and measure residual (free) water are also discussed. [ABSTRACT FROM AUTHOR]

The paper considers technologies for the synthesis of amino-formaldehyde resins of KF-MT-NP and AFK-10 grades obtained using the peptization procedure, which could result in the complete elimination of vacuum drying and contribute to the ecologization of the process of synthetic resins production. A modifying additive, which is an inorganic polymer (IP) capable of efficient binding of free formaldehyde in the resin and stabilizing its properties by extending its viability to 6–7 months, is used as a peptizer. [ABSTRACT FROM AUTHOR]

Abstract One major limitation of effective vaccine delivery is its dependency on a robust cold chain infrastructure. While Vesicular stomatitis virus (VSV) has been demonstrated to be an effective viral vaccine vector for diseases including Ebola, its −70 °C storage requirement is a significant limitation for accessing disadvantaged locations and populations. Previous work has shown thermal stabilization of viral vaccines with a combination of pullulan and trehalose (PT) dried films. To improve the thermal stability of VSV, we optimized PT formulation concentrations and components, as well as drying methodology with enhanced vacuum drying. When formulated in PT films, VSV can be stored for 32 weeks at 4 °C with less than 2 log PFU loss, at 25 °C with 2.5 log PFU loss, and at 37 °C with 3.1 log PFU loss. These results demonstrate a significant advancement in VSV thermal stabilization, decreasing the cold chain requirements for VSV vectored vaccines.

The main goal is to build a mathematical model to describe the heat and moisture transfer process and experiment to determine the appropriate vacuum drying mode for Pyinkado wood material. According to the objective above, research has been conducted using the infrared vacuum drying method for Pyinkado, and a mathematical model has been developed to represent the heat and moisture transfer processes during the drying process. Solve mathematical models using the finite element method. Comsol Multiphysics software is used to simulate the drying process. Results are shown through images and temperature and humidity distribution charts. Experimental results recorded the distribution of temperature and humidity during the vacuum drying process of Pyinkado, compared with results calculated from a mathematical model with profiles and trends consistent with the drying experiment. The largest average error when drying using the infrared radiation vacuum method is less than 5%. Determine the appropriate technological parameters for the vacuum drying process of wood with a thickness of 50 mm. The parameters are as follows: drying temperature Ts = 58.9 °C, pressure p = 0.2 bar, and infrared radiation intensity Phn = 625– 641 W/m2.

By increasing the permeability of the cell membrane of the treated material, pulsed electric fields (PEF) enhance the internal transport of various chemical substances. Changing the distribution of these components can modify the chemical and thermal properties of the given material. This study aimed to analyze the impact of PEF (1 kV/cm; 1 and 4 kJ/kg) applied to strawberries prior to drying by various methods (convective, infrared-convective, microwave-convective, and vacuum) on the chemical and thermal properties of the obtained dried materials (sugars content, total phenolic content, and antioxidant capacity (ABTS and DPPH assays); thermal properties (TGA and DSC); and molecular composition (FTIR)). PEF could have induced and/or enhanced sucrose inversion because, compared to untreated samples, PEF-pretreated samples were characterized by a lower share of sucrose in the total sugar content but a higher share of glucose and fructose. Reduced exposure to oxygen and decreased drying temperature during vacuum drying led to obtaining dried strawberries with the highest content of antioxidant compounds, which are sensitive to these factors. All PEF-pretreated dried strawberries exhibited a lower glass transition temperature (Tg) than the untreated samples, which confirms the increased mobility of the system after the application of an electric field. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the impact of various drying methods: freeze drying, vacuum drying, convection drying, and convection-microwave drying at microwave powers of 50 W and 100 W, along with process temperatures (40 °C, 60 °C, and 80 °C), on the drying kinetics, selected physicochemical properties of dried celery stems, and their grindability. The Page model was employed to mathematically describe the drying kinetics across the entire measurement range. Convection-microwave drying significantly reduced the drying time compared to the other methods. The longest drying duration was observed with freeze drying at 40 °C. The product obtained through freeze drying at 40 °C exhibited the least alteration in color coordinates, the highest antioxidant capacity, and the greatest retention of chlorophylls and total carotenoids. At a specific temperature, the quality of the product obtained from vacuum drying was slightly lower compared to that from freeze drying. The most substantial changes in the physicochemical properties of the dried product were observed with convection-microwave drying at a microwave power of 100 W. The drying method selected had a significant impact on the energy consumption of grinding, average particle size, and the grinding energy index of the dried celery stems; these parameters worsened as the drying temperature increased. The product with the best quality characteristics and disintegration parameters was achieved using freeze drying at 40 °C. [ABSTRACT FROM AUTHOR]

One major limitation of effective vaccine delivery is its dependency on a robust cold chain infrastructure. While Vesicular stomatitis virus (VSV) has been demonstrated to be an effective viral vaccine vector for diseases including Ebola, its −70 °C storage requirement is a significant limitation for accessing disadvantaged locations and populations. Previous work has shown thermal stabilization of viral vaccines with a combination of pullulan and trehalose (PT) dried films. To improve the thermal stability of VSV, we optimized PT formulation concentrations and components, as well as drying methodology with enhanced vacuum drying. When formulated in PT films, VSV can be stored for 32 weeks at 4 °C with less than 2 log PFU loss, at 25 °C with 2.5 log PFU loss, and at 37 °C with 3.1 log PFU loss. These results demonstrate a significant advancement in VSV thermal stabilization, decreasing the cold chain requirements for VSV vectored vaccines. [ABSTRACT FROM AUTHOR]

The study investigates the impact of different drying methods on the selection of thin-layer drying kinetic models, parameters, and quality for Exocarpium Citreic Grandis. This study investigates the drying characteristics, index constituents content, and microscopic structures of Exocarpium Citreic Grandis slices, subjected to three drying techniques: HAD (at 50, 60, 70 ∘ C), VD (at 50, 60, 70 ∘ C), and MVD (at 1000, 1500, 2000W). A thin-layer drying kinetic model was established. The findings demonstrated that the drying process was primarily dominated by the falling rate phase. When the drying temperature was 70 ∘ C and the microwave power was 2000W, the HAD VD, and MVD took 120, 360, and 20 minutes respectively. By fitting six commonly used thin-layer drying models, it was discovered that the optimal mathematical models for HAD, VD, and MVD were the Page model, the Logarithmic model, and the Page model, respectively. The highest average R 2 values were 0.9963, 0.9965, and 0.9964, and the lowest average RMSE values were 0.01782, 0.01704, and 0.0174 respectively. The effective diffusion coefficient increased with the drying temperature and microwave power, with MVD having the maximum coefficient. As the temperature and microwave power increased, the contents of naringin and rhoifolin decreased. However, the naringin content in MVD was 23.05% and 45.71% higher compared to hot air and VD respectively. The cross-section of Exocarpium Citreic Grandis dried via microwave vacuum exhibited a porous honeycomb structure with uniformly distributed spaces and larger pores, reflecting an expansion effect. The HAD process also resulted in a honeycomb-like structure, but with smaller pores. The VD process resulted in a layered structure with significant cell collapse. Microwave vacuum drying demonstrates superior energy efficiency and product quality compared to hot air and vacuum drying methods. The study finds that microwave drying does not have a destructive impact on the active compounds of Exocarpium Citreic Grandis. To facilitate large-scale, continuous production, microwave drying can be practically applied in industrial processing. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Traditional Chinese Medicine (TCM) aqueous extracts are highly viscous pseudoplastic porous media that boiling during vacuum drying, and the drying mechanism significantly differs from that of conventional solid materials. To reveal the heat transfer mechanism, a simulation model of aqueous extracts nucleate boiling was built based on fractal theory, and the effects of superheat, material temperature, viscosity and contact angle on fractal characteristics and heat transfer were studied. Results demonstrate that within a superheat range from 11 °C and 74 °C, the fractal dimension of active nucleation sites on the drying wall ranges between 1.75 and 1.86. The nuclear boiling heat flux increases with the increase in superheat, material temperature, specific heat capacity, thermal conductivity, and contact angle; or with the decrease in viscosity. The research can offer theoretical guidance for the development of drying processes and the optimization of technology in high viscosity pseudoplastic porous media. [ABSTRACT FROM AUTHOR]

To achieve a krill meal of high quality, a two-stage drying involving hot-air drying and vacuum drying was investigated. Five experimental groups were established according to the different drying conditions in the second stage, including 95 °C and 101 kPa, 95 °C and 60 kPa, 75 °C and 101 kPa, 75 °C and 60 kPa, and 75 °C and 20 kPa. The results showed that reducing the drying temperature and vacuum pressure in the second stage had a significant impact on the drying characteristics, sensory quality, and bioactive compounds of krill meal. Among all five groups, the drying condition of 75 °C and 60 kPa maintained a high drying rate while preserving a phospholipid content of 30.01 mg/kg and an astaxanthin content of 37.41 mg/kg. It also effectively reduced the isomerization of astaxanthin and the oxidation of unsaturated fatty acids. These results suggested that the two-stage drying method may contribute to the production of high-quality krill meal. [ABSTRACT FROM AUTHOR]

[Objective] To improve the drying quality of pumpkins. [Methods] This study conducted experiments on hot air drying, vacuum drying, and combined hot air-vacuum drying, these drying characteristics were evaluated and compared based on unit energy consumption, rehydration ratio, and color difference indicators. Combining BP neural network model with genetic algorithm, combined with entropy weight and weighted scoring method, a multi-objective comprehensive optimization was carried out for the combined hot air-vacuum drying of pumpkins. [Results] Under the same conditions, the highest drying efficiency was hot air drying; And the findings revealed that at drying temperatures was 55 ℃, with a moisture content transition point of 30%, the combined drying method reduced the drying time by 52.63%, compared to vacuum drying. The lowest unit energy consumption was vacuum drying; The worst rehydration performance was hot air drying. The best color was vacuum drying. The optimal drying parameters determined by the genetic algorithm combined with a BP neural network model were a hot air drying temperature of 65 ℃, conversion point moisture content of 50%, and vacuum drying temperature of 56.050 9 ℃. Verification experiments demonstrated that the average relative errors between the genetic algorithm optimized values and the experimental values for unit energy consumption, rehydration ratio, and color difference were 2.5%, 5.53%, and 4.84%, respectively, all lower than 6%. [Conclusion] The combined hot air-vacuum drying of pumpkin integrates the advantages of both hot air drying and vacuum drying, and combined with BP neural network genetic algorithm model can optimize the process parameters for pumpkin hot air vacuum drying.

Objective: This study aimed to explore suitable drying methods for oil tea powder, making it easier for oil tea consumption and storage. Methods: Spray drying, vacuum freeze drying and vacuum drying were used to dry oil tea soup, and the quality (moisture content, sensory evaluation and color) and volatile substances of dried oil tea powder were evaluated. Results: The sensory score of vacuum freeze-drying oil tea powder was the highest (93), the water content was the lowest (3.78%), and the color was better（ΔE value 49.74). 104 volatile substances were identified from three drying methods of oil tea powder using SPME-GC-MS technology, of which 14 affected the flavor of oil tea powder. The characteristic flavor substances (nonanal, decanal, (Z)-2-decanal, (Z)-2-nonenal, (E) -3,7-dimethyl-2,6-octadienal) of freeze-drying present green fragrance and fat fragrance. The special aromas of spray drying and vacuum drying are (Z)-3,7-dimethyl-2,6-octadienal, (E)-3,7-dimethyl-2,6-octadienal and decanal, presenting green fragrance, fruit fragrance, and wax fragrance. PCA and comprehensive evaluation indicate that vacuum freeze-drying has the best flavor quality, which is consistent with sensory evaluation results. Conclusion: The flavor quality of vacuum freeze-drying was the best.

Relevance. Fermentation makes it possible to improve the properties of the final product, increase its nutritional value and organoleptic characteristics. It has been scientifically proven that the use of fermented foods (with high nutritional and biological value) on a regular basis has a positive effect on human health, increases immunity, improves the functioning of the gastrointestinal tract. Dry fermented products with a long shelf life can be recommended as part of the diet in space. The aim is to creation of a dry base for fermented long-term storage beverages based on cabbage and table carrots, applicable in the diet of space nutrition. Objects and methods of research. The objects of the study were the domestic hybrid of white cabbage F1 Severyanka and the domestic variety of carrot table Margosha, and the dry fermented products obtained from them. Results. It was found that, according to biochemical and organoleptic quality indicators, the domestic hybrid of white cabbage F1 Severyanka and the domestic carrot variety Margosha are suitable for various types of processing, including fermentation and manufacture of dried fermented products. The comparison of the number of microorganisms in fermented cabbage and cabbage dehydrated by LTVD (low temperature vacuum drying) and VFD (vacuum freeze drying methods was carried out. The survival rate of microorganisms was 1.62 times higher in LTVD. The ways of accelerating the fermentation process of table carrots are considered. The expediency of using starter cultures obtained on the basis of the fermented product has been confirmed. It has been found that using starter cultures in the form of a fermented product dried by the LTVD method accelerates fermentation and allows you to reach the desired pH level 1.33 times faster than the base one and does not affect the final organoleptic characteristics.

AbstractFish protein concentrate (FPC) is considered as a promising alternative to overcome the world’s shortage of affordable animal-based protein. Snakehead fish (Channa striata) offers a large potential as a raw material for FPC manufacture. This work aims to investigate the influence of solvent types (ethanol, n-hexane, and an azeotrope mixture of ethanol + n-hexane), extraction time (0, 10, 15, 20, 25, and 30 minutes), temperature (30, 40, 50, and 60°C), liquid solvent volume to solid feed fish flesh mass ratio (LSSFR) (1, 2, 3, 4, 5, 6, and 7 mL/g), and ultrasonic power (100, 200, 300, and 400 W) on the ultrasound-assisted extraction (UAE) to manufacture high-quality FPC from snakehead fish. After being subjected to UAE, the fish flesh was filtered and dried under reduced pressure at 55°C. The optimum UAE conditions for the manufacture of FPC from snakehead fish flesh were using ethanol as solvent, LSSFR (6 mL/g), temperature (40°C), ultrasonic power (200 W), and extraction time (25 minutes). The resulted FPC can be categorized as type A, which contains protein (73.17%) and fat (0.73%). An SDS-PAGE electrophoresis evaluation proved that the FPC contained 12 types of peptides having molecular weight (MW) ranging from 4.00 to 174.00 kDa with the major fractions being those with MWs ranged from 4.00 to 11.00 kDa and the minor fractions with MWs between 71.70 to 174.00 kDa. Indeed, the presence of both low and high MW peptides in the FPC indicates its potential applications in the development of nutritious food products.

Developing novel, energy-saving, and facile approaches to constructing high-performance aerogels is still challenging. Aerogels are most commonly produced by freeze-drying and supercritical drying that require expensive specialty equipment or ambient drying lengthily of solvent exchange precursors. Here, we report a compensation strategy using acrylamide as an assisting solute to enable the construction of conductive polymer aerogels by simple vacuum drying of frozen solids of aqueous poly(3,4-ethylene dioxythiophene)/poly(styrene sulfonate) (PEDOT/PSS). In this approach, the acrylamide crystal sublimates slowly at an elevated temperature (80 or 110 °C) to maintain the porous structure of PEDOT/PSS in the solid-state during water evaporation. By tuning PEDOT/PSS to acrylamide weight ratios and drying temperatures, aerogels were produced with low density (6.3–21.6 mg/cm3), high porosity (>99 %), and low shrinkage (5.3 %). Additionally, acrylamide increases the electrical conductivity of PEDOT/PSS by three orders of magnitude (from 0.01 to 81.1 S/m). Morphology and physical properties are further analyzed to reveal aerogel formation and the conductivity enhancement mechanism. These aerogels are then applied as water-induced electric generators for green energy harvesting. The current work provides an alternative and simplified approach to rapidly fabricating various nanomaterial-based aerogels, replacing the slower and more expensive freeze-drying and supercritical drying.

The present work aimed to characterise oven-dried honey-sugar powders at vacuum temperatures (30 and 40°C) with dextrose, maltodextrin, and sucrose as the sugar carrier (incorporated at 50, 60, and 70%) for application in chocolate. Honey has high water content, and therefore, its direct use in chocolate will negatively affect the rheological properties of chocolate. Dextrose can produce a honey powder with the least heat degradation, hence maintaining the good health functionality of honey. Maltodextrin is the most common carrier used in honey-powder processing, while sucrose is the most common ingredient used in chocolate. The physical appearance and other physicochemical properties such as moisture content, hygroscopicity, glass transition temperature, hydroxymethylfurfural (HMF) content, and diastase activity were assessed for characterisation. Results showed that the honey-sugar powder that was dried at 40°C with 70% sugar carrier exhibited better properties in terms of physical appearance, moisture content, and hygroscopicity, with the HMF content and diastase activity not significantly affected by both factors. Therefore, honey-sugar powders dried at 40°C with 70% sugar carrier incorporation could have further application in chocolate. The impact of honeysugar powder on chocolate rheological properties and their functionality in promoting health benefits is crucial for their potential application in the future. [ABSTRACT FROM AUTHOR]

Sweet potato is rich in carotenoids and fiber and confers sweetness to the product in which it is utilized. The aim of the research was to utilize sweet potato in the form of ‘osmo-vac’ dehydrated powder in medium-fat (6.0% fat) ‘chocolate ice cream’ for value-addition. Use of sweet potato powder (SPP) at 2.0 to 4.0% level did not affect the sensory quality of chocolate ice cream appreciably. SPP when used at 4.0% level in ‘medium-fat’ chocolate ice cream led to enrichment of the ice cream with β-carotene and fiber; it could replace 40.0% of milk fat and 10.0% of sugar in ice cream. Ice cream containing 4.0% SPP tended to have markedly higher total carbohydrates and total solids content as compared to control ‘medium-fat’ ice cream. Presence of SPP in ice cream led to slight impairment in its overrun. The ‘medium-fat’ chocolate ice cream prepared utilizing 4.0% SPP had sensory scores similar to those of ‘full-fat’ (10.0% fat) control ice cream. Ice cream is an ideal medium for utilizing sweet potato solids contributing to value-addition to the frozen delicacy. [ABSTRACT FROM AUTHOR]

Summary: The aim of this study was to produce high‐quality dried chicken meat slices by a low‐temperature vacuum drying system. Chicken meat slices were cut in 2 and 4 mm thicknesses and then dried at the temperatures of 10 and 20 °C and the pressures of 1, 0.85 and 0.70 atm. The mean moisture content, water activity (aw) and pH values of the low‐temperature vacuum dried chicken slices were 41%, 0.90% and 6.23%, respectively. Depending on the temperature increase, the non‐protein nitrogen (NPN) (P < 0.01) value increased from 5.49 g per 100 g to 6.13 g per 100 g, and the thiobarbituric acid reactive substances (TBARS) (P < 0.01) value increased from 13.33 to 17.89 μmol MDA kg−1. The colour of samples changed from a lighter and yellow to a darker and brownish as the drying temperature, pressure and thickness increased. The cutting force was higher at 2 mm thickness (18.42 N) (P < 0.01) and 0.70 atm pressure (17.12 N) (P < 0.05) conditions. The samples dried at 10 °C, 0.70 atm and 2 mm had higher microbiological quality and the highest overall acceptability score (7.57). [ABSTRACT FROM AUTHOR]

The time domain nuclear magnetic resonance (TD-NMR) technique was employed to distinguish various water states, and the moisture migration during Elm wood (Ulmus rubra) heartwood vacuum drying was quantitatively analyzed. The transverse relaxation time (T2) was employed to establish the correlation between drying time and moisture migration. Additionally, the longitudinal relaxation time (T1) was utilized to identify two types of water states within the cell wall: OH bound water (B-water) and more freely bound water (C-water). Meanwhile, the changes in these two types of bound water during the drying were investigated. The results demonstrated an exponential decrease in the content of OH bound water and more freely bound water with drying time. OH bound water within the cell wall predominated, with only a small portion of more freely bound water experiencing migration loss when the moisture content (MC) dropped below 20 %. Furthermore, OH bound water exhibited higher migration rate compared to more freely bound water at 10–20 % MC, while the motion of OH bound water molecules became highly restricted and stronger binding to cell walls than more freely bound water at a MC level of below 10 %. These findings yield a theoretical foundation and empirical support for optimizing drying methods. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract In this study, the effect of stacking position in the dryer on the drying rate during radio-frequency vacuum combined with mechanical press (RF/VP) drying was investigated for Douglas-fir and Radiata pine. Drying test was performed at a temperature of 40 °C using RF/VP dryer with approximately 3 m3. The results showed that the stacking position has a significant effect on the drying rate, with a more pronounced decrease in drying rate as the stacking position of specimens approaches the ground plate. Previous moisture content was an important factor in determining the drying rate in both species. The MC distribution of specimens in the dryer before drying was very irregular, but over time, specimens stacked on the RF charge plate side in the dryer tended to have lower MC distributions than those stacked on the ground plate side, which was serious at the specimens in contact with the upper ground plate. In addition, as the MC decreases below the fiber saturation point during RF/VP drying, the difference in MC distribution within the dryer according to the stacking position became clearer. These findings provide new insights into the effect of stacking position on drying rate during the RF/VP drying and are expected to improve RF/VP drying technology.

To enhance the performance of inkjet OLED/QLED devices, achieving a uniform film during the drying process is crucial. This study aims to improve both intra‐pixel and inter‐pixel uniformity in the drying process of inkjet printing technology. We conducted a comprehensive analysis of drying characteristics under various mixed solvent boiling points in nitrogen(N2) conditions. Additionally, during vacuum drying process, we carefully studied the characteristics based on adjustments in vacuum pressure and heating. Our focus was on analyzing the thickness profiles of dried pixel arrays in different positions: top, center, bottom, and left parts. Through the optimization of vacuum drying using solvents with a high boiling point (BP), we successfully achieved uniform film formation within and between pixels in inkjet‐printed pixel arrays. [ABSTRACT FROM AUTHOR]

The effects of hot air (HAD), vacuum (VAD) and conductive (CD) drying on the chemical and textural profiles of Cucurbita maxima pulp were investigated to find suitable drying conditions to avoid postharvest losses of pumpkin. The results showed that the drying methods had a significant effect (p < 0.05) on the chemical and textural profiles of pumpkin pulp. The ash content was lower in VAD (up to 7.65%) than in HAD (up to 9.88%) and CD pulp (up to 9.21%). The samples of HAD, CD and VAD had a higher fat content, up to 3.07, 2.66 and 2.51%, respectively, than fresh pulp (1.55%). The total fibre content is lower for VAD (up to 8.78%) than for HAD (up to 15.43%) and CD pulp (13.94%). HAD pulp at 70 °C (~15.51%) and VAD and CD pulp processed between 50 and 60 °C (~22%) are good sources of protein. HAD and CD pulp at 70 °C and VAD at 50 °C resulted in a high sugar content (up to 83.23%). In addition to drying, the extraction time of 40 min used in ultrasound-assisted extraction is optimal, especially for protein and sugar recovery in dried samples. Drying also led to strong changes in the textural properties of the pulp, so that an excellent dried intermediate product is the one obtained using HAD at a temperature of 70 °C and an airflow of 0.5 m/s. [ABSTRACT FROM AUTHOR]

In this study, the effect of stacking position in the dryer on the drying rate during radio-frequency vacuum combined with mechanical press (RF/VP) drying was investigated for Douglas-fir and Radiata pine. Drying test was performed at a temperature of 40 °C using RF/VP dryer with approximately 3 m3. The results showed that the stacking position has a significant effect on the drying rate, with a more pronounced decrease in drying rate as the stacking position of specimens approaches the ground plate. Previous moisture content was an important factor in determining the drying rate in both species. The MC distribution of specimens in the dryer before drying was very irregular, but over time, specimens stacked on the RF charge plate side in the dryer tended to have lower MC distributions than those stacked on the ground plate side, which was serious at the specimens in contact with the upper ground plate. In addition, as the MC decreases below the fiber saturation point during RF/VP drying, the difference in MC distribution within the dryer according to the stacking position became clearer. These findings provide new insights into the effect of stacking position on drying rate during the RF/VP drying and are expected to improve RF/VP drying technology. [ABSTRACT FROM AUTHOR]

Agricultural materials (LF products) can be considered biologically living organisms due to their structure and the composition of colloidal capillary-porous substances in them. They contain a large number of microscopic pores, microcapillaries and macrocapillaries, in which water is able to pass from the inner parts to the surface of the grain, and vice versa. Thus, it can be concluded that drying is an important and demanding aspect of agricultural production. To determine the optimal drying process for agricultural cereals from a nutritional, energy, economic and environmental point of view, it is necessary to address in detail the application of the technology of vacuum drying from a thermodynamic point of view. An analysis of the research results shows that drying temperature, harvest date and corn variety can significantly affect the properties of the main components of corn grain. This study investigates the individual technological parameters of the vacuum drying process for corn, such as the pressure used in the drying chamber, the grain drying temperature and the heating time, in order to achieve a maximum reduction in water content. The aim of the investigation is to determine the optimal parameters for the design of a functional prototype of a vacuum dryer. For this purpose, laboratory and semi-operational experiments using different types of organic materials are necessary. The structural design of the individual elements of the vacuum dryer is based on an analysis of laboratory and experimental tests, whose results are presented in this article. [ABSTRACT FROM AUTHOR]

One crucial step in the propellant-making process that takes a lot of time and energy is drying. The study of inert propellants' vacuum drying behaviours – which mimics those of real propellants – is the main focus of this work. This study presents the development of analytical and numerical models for the vacuum drying of inert propellants, which were validated through an in-house vacuum drying experiment. The calculation of effective diffusivity, a crucial parameter characterising the rate of solvent vapour transfer during the vacuum drying of inert propellant samples, is one of the outcomes of this work. It involves removing liquid solvents from the texture of a propellant. Conclusions and suggestions for technical practice are developed based on the studyʼs findings. [ABSTRACT FROM AUTHOR]

Chayote (Sechium edule) fruits have very high moisture content and very soft skins, thus susceptible to spoilage and mechanical damage. Furthermore, due to a lack of suitable storage, transport and processing facilities, huge losses are incurred in terms of quality and quantity. Therefore, the study was conducted to optimise the process parameters of vacuum drying of chayote slices to produce a good quality dehydrated product. The experiments used slice thicknesses of 1, 3, and 5 mm at different temperatures (54 to 66°C). From the analysis using full factorial design and Duncan's multiple range tests, it was observed that the optimum responses (final moisture content, rehydration ratio, energy consumption, production rate, and total cost) were obtained during vacuum drying of 1 mm chayote slices at 58°C. The results were at par with the treatment consisting of vacuum drying of 3 mm chayote slices at 58°C. From experience, slicing the chayote to 1 mm thickness was too difficult; hence, treatment at 58°C and 3 mm slice thickness may be considered as optimum process condition, which produced dried product with a moisture content of 3.5% at a production rate of 1.662 g d.p./h and had a rehydration ratio of 5.833. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the impact of various drying methods: freeze drying, vacuum drying, convection drying, and convection-microwave drying at microwave powers of 50 W and 100 W, along with process temperatures (40 °C, 60 °C, and 80 °C), on the drying kinetics, selected physicochemical properties of dried celery stems, and their grindability. The Page model was employed to mathematically describe the drying kinetics across the entire measurement range. Convection-microwave drying significantly reduced the drying time compared to the other methods. The longest drying duration was observed with freeze drying at 40 °C. The product obtained through freeze drying at 40 °C exhibited the least alteration in color coordinates, the highest antioxidant capacity, and the greatest retention of chlorophylls and total carotenoids. At a specific temperature, the quality of the product obtained from vacuum drying was slightly lower compared to that from freeze drying. The most substantial changes in the physicochemical properties of the dried product were observed with convection-microwave drying at a microwave power of 100 W. The drying method selected had a significant impact on the energy consumption of grinding, average particle size, and the grinding energy index of the dried celery stems; these parameters worsened as the drying temperature increased. The product with the best quality characteristics and disintegration parameters was achieved using freeze drying at 40 °C.

By increasing the permeability of the cell membrane of the treated material, pulsed electric fields (PEF) enhance the internal transport of various chemical substances. Changing the distribution of these components can modify the chemical and thermal properties of the given material. This study aimed to analyze the impact of PEF (1 kV/cm; 1 and 4 kJ/kg) applied to strawberries prior to drying by various methods (convective, infrared-convective, microwave-convective, and vacuum) on the chemical and thermal properties of the obtained dried materials (sugars content, total phenolic content, and antioxidant capacity (ABTS and DPPH assays); thermal properties (TGA and DSC); and molecular composition (FTIR)). PEF could have induced and/or enhanced sucrose inversion because, compared to untreated samples, PEF-pretreated samples were characterized by a lower share of sucrose in the total sugar content but a higher share of glucose and fructose. Reduced exposure to oxygen and decreased drying temperature during vacuum drying led to obtaining dried strawberries with the highest content of antioxidant compounds, which are sensitive to these factors. All PEF-pretreated dried strawberries exhibited a lower glass transition temperature (Tg) than the untreated samples, which confirms the increased mobility of the system after the application of an electric field.

Jamur kancing merupakan komoditas hasil pertanian yang mudah rusak sehingga harus segera ditangani setelah panen. Salah satu cara untuk mengawetkan jamur kancing adalah melalui proses pengeringan vakum. Pengeringan vakum bekerja dengan menguapkan air pada tekanan rendah sehingga titik uap air tercapai pada suhu rendah dengan waktu yang lebih singkat. Kombinasi blanching dan dehidrasi osmotik diharapkan dapat mencegah proses pencoklatan pada jamur kancing. Tujuan penelitian ini adalah menganalisa perubahan warna jamur kancing selama proses pengeringan vakum dengan pra-perlakuan blanching dan dehidrasi osmosis dengan penambahan asam askorbat serta menentukan pemodelan perubahan warnanya. Dalam penelitian ini, dilakukan konversi atribut warna pada image perubahan warna jamur kancing selama pengeringan vakum pada suhu 35, 45 dan 55 °C dengan kombinasi pra-perlakuan blanching dan dehidrasi osmosis. Delapan model matematika empiris perubahan warna digunakan untuk menentukan model terbaik. Hasil penelitian menunjukkan bahwa pengeringan pada suhu 35 °C mampu menghambat pencoklatan jamur kancing yang tampak dari nilai atribut warna L*, a*, b* dan ( . Model NIST Hahn 1 dan Power merupakan model terbaik yang mampu menjelaskan perilaku perubahan warna pada pengeringan vakum jamur kancing berdasarkan uji ketepatan R², RMSE, dan nilai X².

Introduction Sweet Pepper (Capsicum annum) has a very important place among the vegetables produced in the world. Therefore, it is necessary to apply practical solutions to increase their sustainability to develop and improve production. The growing consumer rejection of chemical additives and the demand for more natural products have increased attention to some methods, including the drying method. One of the physical changes that occur during the drying of food is its reduction in volume. Vacuum drying is a method in which water and other solvents that have been absorbed into the volume or surface of the material are removed. Combining vacuum with heating can be an effective way to dry; because in this case, a high level of dryness can be achieved without the need for a large increase in temperature. A thermal process that is applied to vegetables and fruits as a pre-process step for freezing, drying and canning to inactivating enzymes, modifying texture, preserving flavor and nutrients, and extracting Interstitial air. Materials and Methods This study aimed to investigate the impact of various factors ethyloleate (concentrations 0,2,4%), sodium chloride(concentrations 0,2,4%) and blanching on the drying kinetics, physical properties, chemical composition and nutrients of green bell pepper, dried under vacuum at 60°C and pressure of 10 kpa using the response surface methodology. At the end of the drying time, 10 g of the treated samples were weighted to investigate the drying kinetics and the rest of the samples were kept for analysis. To achieve the drying kinetics, the samples were taken out of the oven (Behdad Company, model 3494, made in Iran) at 30 minute intervals and weighed by a digital scale, and dried down to moisture content of 12% ., and then for relevant analyzes on dried samples, the samples were stored in plastic packages until the day of experiments. Investigation of independent and interaction effects of immersion in different concentrations of sodium chloride and ethyloleate solution on the kinetics and drying time separately in blanching and non-blanching samples on the parameters of color, chlorophyll content, phenolic substances and vitamin C remaining in dried Sweet peppers were evaluated using minitab16 software and response level method (RSM). Results and Discussion The results showed that the drying process occur in the range of falling rate and also effect blanching in boiling water for 3 minutes and immersed in an alkaline solution of ethyloleate and sodium chloride with concentrations of 2 and 4% for 1 minute, significantly increase the drying rate. In blanching and treated samples with 4% ethyloleate and sodium chloride, the drying time was about 3.5 hours, while the control sample was dried under the same conditions for 7.5 hours. Pretreatment of samples, showed the chlorophyll content, phenolic compounds and vitamin C were higher than the control sample. Due to the effectiveness of ethyloleate in the protection of ascorbic acid, phenolic compounds and residual chlorophyll, the highest amount of ascorbic acid with a value of 39.77 was related to the samples treated in ethyloleate solution with a concentration of 4% and 4% NaCl and the minimum value of 17.98 was related to the control treatment. The highest amount of residual chlorophyll was 23.6 in the pretreated samples with a concentration of 4% ethyloleate and 4% NaCl and the lowest amount was related to the control sample with a concentration of 12.9%. The color of the dried samples showed that the lowest amount of color changes was related to the non-blanching sample with 4% ethyloleate and 4% NaCl with a value of 4.94. While the blanching and ethyloleate solution had no positive effect on the color of pepper and dried samples were dark. Comparison of blanching with non-blanching shows that blanching samples cause darkening of the primary color of the samples.The best sample in terms of quality and speed of drying, was belonged to the samples which blanched, treated with 4% solution of ethyloleate and sodium chloride. Conclusion In order to achieve the best quality in vacuum drying of pepper samples, pretreatments of blanching and using a concentration of 4% solution of ethyloleate and sodium chloride showed the most desirable quality. The best quality of dried samples were obtained when subjected to constant temperature and pressure during drying conditions. The benefits obtained using the pretreatment of ethyloleate and sodium chloride as an appropriate method of drying include increasing the absorption of water, keeping the chlorophyll, phenolic compounds and vitamin C content with time-saving in drying.

This study was aimed at researching the impact of the drying procedure (using the most appropriate honey–maltodextrin concentration for each drying technique) and botanical origin of honey on the physicochemical and potentially bioactive properties of honey powders that were made using maltodextrin as a carrier. The research was carried out with thyme, lavender, vetch and multifloral honey dehydrated using vacuum drying and freeze drying. The analysed parameters were moisture, water activity, colour, glass transition temperature, powder recovery, hygroscopic index and rate, tapped density, solubility, and phenolics as well as antiradical (ABTS•+, ROO•, •OH and O2•−), anti-inflammatory and antimicrobial (against Staphylococcus aureus, Escherichia coli and Listeria monocytogenes) activities. Freeze drying provided the highest recoveries. Powders obtained using freeze drying showed higher moisture and solubility as well as lower glass transition temperature, density and hygroscopicity than those obtained using vacuum drying. Hygroscopicity, glass transition temperature and antimicrobial activity against St. aureus depended on the drying procedure–honey concentration. Colour, anti-O2•− activity and antimicrobial activity against L. monocytogenes depended on the botanical origin of the raw honey. Moisture, solubility, density, total phenolic content, anti-ABTS•+ and anti-ROO• activities as well as anti-inflammatory activity and antimicrobial activity against E. coli depended on the drying procedure–honey concentration and botanical origin. [ABSTRACT FROM AUTHOR]

A novel approach of instant decompression‐induced swell drying also known as instant controlled pressure drop‐hot air dried (ICPD‐HAD) process was applied for the process performance and quality enhancement of dried banana slices. Using a hybrid approach of particle swarm embedded methodology, the process parameters treatment pressure (TP), treatment time (TT), and duration of decompressed State (DDS) were optimized for various responses including drying time (DT), browning index (BI), rehydration ratio (RR), and total antioxidant activity (TAA). The optimized process conditions were found to be 0.1 MPa of TP, 25 s of TT, and 12 s of DDS for a minimum DT of 225 min and, maximum BI, RR, and TAA, of 6.20%, 3.40%, and 98.78% respectively. The results also demonstrated that the dried banana samples produced by the ICPD‐HAD method exhibited superior quality in terms of minimal DT and BI and maximum TAA and RR compared to those produced by the vacuum and hot air drying techniques. Microstructural investigation demonstrating the superiority of ICPD‐induced samples provided additional evidence for the minimum DT requirement. Furthermore, the use of an artificial neural network was employed to investigate the drying kinetics of the novel instant decompression‐induced swell drying process. With R2 greater than 0.99 and a minimum mean square error (MSE) of 0.000131, the 2‐4‐1 artificial neural network (ANN) architecture performed admirably as a means of optimal simulation and robust control of the drying process. Practical applications: Instant decompression‐induced swell drying also known as ICPD‐HAD process is a novel approach for the drying of banana sample with enhanced process performance and quality attires. It is common for banana drying to cause loss of total antioxidant activity and other important functional properties like color and texture. This issue can be solved and process performance can be enhanced with less energy use by employing an innovative swell drying technique triggered by instant decompression. Therefore, the dried banana samples made using this cutting‐edge technique will be advantageous from a health point of view. This method can be used by the food manufacturing sector to produce dried bananas of a higher quality and greater consumer acceptance. [ABSTRACT FROM AUTHOR]

Background: Brown rice (BR) is a traditional health food that has high active compounds which have effective preventive and therapeutic effects on many diseases. Brown rice (Oryza sativa) is a healthy grain that has several advantages for infant health compared to white rice. It is one of the healthiest and most researched forms of rice that contains complex carbohydrate giving the feel of satiety and fullness. Due to its high natural nutrition content and fiber content, BR cereal makes the ideal first solid food for infants. Aim: In the current study, the impact of freeze and vacuum drying on the retention of macro and micronutrients was examined. Methods: Freeze drying was carried out at a temperature − 45° ± 5 °C under a vacuum of 10 Pa absolute pressure and vaccum drying was carried out at 40 °C with a vacuum pressure of 76 cm Hg. The proximate composition and micronutrient were analysed as per standard Association of official analytical collaboration (AOAC) methods. Atomic absorption spectroscopy and high-performance liquid chromatography were used to determine the minerals and vitamins in the products and samples. Results: The micronutrient content of the freeze-dried sample was found to contain 42.87 ± 0.13 mg/100 g of potassium, 6.6 ± 0.10 mg/100 g of sodium, 1.39 ± 0.02 mg/100 g of iron, 1.25 ± 0.01 of zinc, and 0.45 ± 0.02 mg/100 g of vitamin B6, whereas the micronutrient content of vacuum-dried powder contains 40.21 ± 0.09 mg/100 g of potassium, 6.4 ± 0.11 mg/100 g of sodium, 1.25 ± 0.01 mg/100 g of iron, 1.08 ± 0.02 of zinc, and 0.42 ± 0.02 mg/100 g of vitamin B6. Conclusion: The results showed that retention of micronutrients in brown rice porridge was high in freeze drying compared to vacuum drying. [ABSTRACT FROM AUTHOR]

Fructooligosaccharides (FOS) is a functional food additive. FOS syrup produced by biological methods can be easily transported, stored and used after drying. In this study, the effects of operating pressure, heating temperature and initial moisture content of FOS syrup on the drying characteristics during vacuum drying were studied. With a visual system, the state changes of the material during the drying process were recorded. The specific heat, viscosity and thermal conductivity of the FOS at different temperatures and moisture contents were measured. From the perspective of drying characteristics, the whole drying process can be divided into four periods: the increasing drying rate period AB, the first falling drying rate period BC, the second falling drying rate period CD and the third falling drying rate period DE. The heat transfer mode in AB and BC was boiling heat transfer, with the material viscosity less than 267.9 Pa·s. In CD period, the heat transfer mode was convection heat transfer with the material viscosity of 267.9 Pa·s to 501.6 Pa·s. In DE period, the material viscosity was greater than 501.6 Pa·s and did not have fluidity, and the heat transfer mode was heat conduction. A multivariate model for the convection heat transfer coefficient was obtained based on the heat balance. The maximum error between the simulation value by the model and the experimental value of the material moisture content during the vacuum drying process was 4.18 %. [ABSTRACT FROM AUTHOR]

The article studied the patterns of changes in water activity during vacuum drying of apple varieties: Baiterek, Sarkyt and Saya and pear varieties: Syilyk, Zhazdyk and Nagima. Studies have established that in all the studied varieties of apple and pear, the following pattern is observed: in the first four hours of the drying time, the water activity indicator decreases monotonously, and the subsequent drying time drops sharply. This pattern is explained by the fact that after four hours of drying time, part of the remaining weakly bound moisture is gradually removed from the product, and then the bound moisture. Studies have shown that dehydration of fruits, the water activity characterizing the qualitative properties of the product decreases: for apple varieties from 1.0 to 0.62 ± 0.01, for pear varieties this indicator decreases from 1.0 to 0.65 ± 0.04. On the basis of mathematical processing of experimental data, a power-law dependence of water activity on the duration of drying was established. The established pattern of changes in water activity from the duration of drying in subsequent works will be used to determine the optimal drying mode for apples and pears in order to produce high-quality dry powders for the food industry.

To achieve a krill meal of high quality, a two-stage drying involving hot-air drying and vacuum drying was investigated. Five experimental groups were established according to the different drying conditions in the second stage, including 95 °C and 101 kPa, 95 °C and 60 kPa, 75 °C and 101 kPa, 75 °C and 60 kPa, and 75 °C and 20 kPa. The results showed that reducing the drying temperature and vacuum pressure in the second stage had a significant impact on the drying characteristics, sensory quality, and bioactive compounds of krill meal. Among all five groups, the drying condition of 75 °C and 60 kPa maintained a high drying rate while preserving a phospholipid content of 30.01 mg/kg and an astaxanthin content of 37.41 mg/kg. It also effectively reduced the isomerization of astaxanthin and the oxidation of unsaturated fatty acids. These results suggested that the two-stage drying method may contribute to the production of high-quality krill meal.

Açaí is a fruit native to Brazil that is found in Colombia, and it is recognized for containing more than 90 compounds with anticancer, anti-inflammatory, and other biological activities. In this study, a cradle-to-gate life cycle analysis (LCA) was conducted for the production of açaí powder, following the methodology outlined in the ISO 14040 standard. The investigation focused on examining the impact of utilizing or not utilizing the residues generated during the pulp extraction step as fertilizers. Four scenarios were analyzed and compared: (i) production of açaí powder via vacuum drying, (ii) via spray drying, and via the same two types of drying but using residues from the pulping operation as fertilizer (Scenarios 3 and 4). It was found that to produce 1 kg of açaí in a crop cycle, 1.17 kg of CO2 eq is produced. The drying stage in Scenarios 1 and 2 generated 8.04 and 7.93 kg of CO2 eq, respectively. Similarly, when solid waste is used as fertilizer, CO2 emissions barely increased for Scenarios 3 and 4, respectively. To the authors' knowledge, this is the first carbon footprint study of the production of açaí powder whit these scenarios. [ABSTRACT FROM AUTHOR]

This study suggested a combination of microwave and vacuum drying to meet the requirements of preserving the nutritional content of fresh poniol fruit, consuming lower energy, and having a faster drying rate. In this study, the influence of microwave power, vacuum level, and citric acid pretreatment level on the product quality of dried poniol was analyzed. The citric acid pretreatment was conducted in an ultrasonicator bath. The pretreated was dried by changing the microwave power (XP) from 400 to 800 W and the vacuum level (XV) from 300 to 600 mmHg. The quality of the dried product was analyzed in terms of total phenolic content (YPC), antioxidant activity (YAA), total change in color (YCC), and rehydration ratio (YRR) of dried poniol fruit. The response range in the sequence was between 22.219–38.361 mg GAE/g, 69.037–92.578 %DPPH inhibition, 23.451–40.148, and 1.38–3.81, respectively, at various combinations of independent variables. The optimal combination of independent variables for maximal recovery of total phenolic content, antioxidant activity, rehydration ratio, and minimal color changes was obtained at 440 W power level, 600 mmHg vacuum, and pretreated with citric acid of concentration.8%. Under the optimum combination of independent variables, the total phenolic content, antioxidant activity, rehydration ratio, and total color change values were 37.904 mg GAE/g, 92.973%, 23.906, and 3.307, respectively. Because of the low temperature in the vacuum process combined with the rapid heating time of microwaves, the results indicate that microwave vacuum drying might be a viable alternative method for improving the quality of dried food products. Practical Applications: Microwave vacuum drying is a technology that uses microwave radiation to generate heat in the absolute pressure range between the triple point of water and atmospheric pressure. Heat is generated in microwave vacuum drying by directly converting electromagnetic energy into kinetic molecular energy. Hence, heat is generated deep inside the product being dried. Because interior temperatures are greater than exterior temperatures, evaporating water is driven to the surface, resulting in higher partial pressure. As a result, the moisture evaporating within the product is released through the pore structure of the macro‐capillary system of the solid material, resulting in a faster drying rate. Since the superficial layer does not dry out completely, the surfaces remain porous. This method results in a superior end product that is also very nutritious with enhanced sensory properties. As a result, this approach is used in the chemical, pharmaceutical, and food industries. [ABSTRACT FROM AUTHOR]

Introduction: In Ayurvedic classics, the potential of herbal medicine is expressed through various dosage forms having multilevel actions. Ksheerapaka is one of the unique preparations of Ayurveda pharmaceutics, where milk is used as the medium for formulation. In general, Ksheerapaka is prepared by boiling the drug with a specific quantity of milk and water and reducing it to quantity. The preparation of ksheerapaka is time-consuming. As milk is the medium of preparation, the stability of the product is low and not travel-friendly. Due to these flaws, a new patient-friendly formulation with less bulk and better stability is intended to be prepared by value addition. Methods: A literature review was done on commonly used ksheerapaka and the value addition of milk products. Three commonly used Ksheerapakas, namely, Arjuna, Sthira, and Lasuna, were selected and prepared by the classical method. Value addition was done by trial and error using different techniques in three different centers. Result and Conclusion: Ksheerapaka prepared by spray drying had the same flavor and taste as the classical preparation and was free-flowing without any grittiness. The appearance and taste were appreciable and easily dissolvable. The product was also stable at room temperature. Spray drying can be recommended for the commercial preparation of Ksheerapaka powder considering the product's cost-effectiveness and efficacy. Unlike other value-added preparations of classical Ayurvedic formulations, Ksheerapaka powder also satisfies the mode of administration like the classical preparation.

Studies have established that various drying periods are observed during the drying process: for example, for apple varieties, the first drying period is 5.45...6.10 hours, and for pear varieties 6.12 ...6.25 hours. The duration of the second drying period for apple varieties is 4.15...3.50 hours, and for pear varieties 4.35...4.48 hours. The analysis of the drying curve showed that the boundary between the periods of constant and falling land velocity, i.e. the critical humidity for apple varieties is on average 27 ± 2.1%, and for pear 30.1 ± 2.5%. An analysis of the kinetics of moisture evaporation shows that in an apple during the first four hours of drying, on average, 2.71 g evaporates, and for the next two hours it decreases monotonically to 2.31 g. The same picture of moisture evaporation dynamics is also observed for pears: for the first four hours, on average, 3.41 g evaporates, and for the next two hours, the evaporation dynamics decreases to 2.78 g. Studies have established that the coefficient of evaporation resistance for apple varieties: Baiterek, Sarkyt and Saya is µ = 2.03 ± 0.07, for pear varieties: Sylyk, Zhazdyk and Nagima is µ = 2.3± 0.05.