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Organic waste management is challenging in low-middle income countries. Environmental impacts and high management costs affect the sustainable development of cities, an issue that is exacerbated by the lack of social involvement. The research conducted in Iran aims to assess the benefits of organic waste home composting in Shiraz to improve solid waste management (SWM) sustainability. The introduction of a pilot project to assess home composting systems was described, together with an economic, social and environmental analysis. The current SWM system (S0) has been compared with the new strategy proposed (S1), where home composting is considered to be introduced to collect about 10% of the municipal solid waste generated in a 10-year horizon. An economic balance related to the capital costs and operational costs of both systems was introduced, in parallel with a life cycle assessment (LCA) of the SWM system, and a questionnaire survey of the local population. Results showed that S1 leads to around 5% economic savings for the municipality due to the avoidance of organic waste transportation and disposal. Environmental benefits include a lowering of CO2-Eq emissions of about 19,076 tonnes year−1. In addition, about 28% of the interviewed (n = 319) agreed to employ the home composting system at home (CI 5.5%, 95% of confidence level) supporting the theory that about 10% of the organic waste can be segregated and home-composted. The research underlines that home composting can contribute to improve the sustainability of SWM systems in developing countries. [ABSTRACT FROM AUTHOR]

Camel meat is a source of high-quality meat with high nutritional value for human beings. In this study, the process of airdried camel meat was optimized by single factors such as the air-drying time, salt addition and curing time, and response surface methodology. Based on the determination of moisture content, weight loss rate and chromatic value, the pH value, lipolytic enzymes activity, lipoxygenase activity, peroxide value, and the thiobarbituric acid reactive substances value indicated the lipolysis and lipid oxidation during the processing of air-dried camel meat. According to the results, the optimal condition of air-dried camel meat process was air-drying time of 8 days, salt addition of 2.6%, and curing time of 3 days. Under these conditions, the hardness and elasticity of air-dried camel meat were moderate. With the extension of air-drying time, the moisture content of air-dried camel meat decreased, the weight loss rate increased, and the chromatic value decreased. The activity of neutral lipase increased significantly in the curing stage (P < 0.05), and the activity of acid lipase and phospholipase increased significantly in the later periods of air drying (P < 0.05). The pH value decreased first and then increased in the air-drying stage. Lipoxygenase activity, peroxide value, and thiobarbituric acid reactive substances value increased during processing. This study showed that the lipids were hydrolyzed and oxidized to some extent during the processing of air-dried camel meat, which contributed to form the flavor quality of air-dried camel meat. [ABSTRACT FROM AUTHOR]

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials 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.)

Drying herbs is a crucial method for stabilizing and preserving their essential properties and bioactive compounds. Although freeze drying is the preferred method for most herbs, it is expensive due to high energy consumption and operating costs. Biflavonoids are dimeric flavonoids that have recently been recognized as potential molecules possessing biological activities, such as antiviral and antimicrobial activity, and as effective molecules for the treatment of neurodegenerative and metabolic diseases and for cancer therapies. In this study, we performed a comparative analysis of freeze drying, air drying and oven drying to evaluate their effects on biflavonoid content in yellow ginkgo leaves (Ginkgo biloba L.). After drying, we performed spectrophotometric analysis to determine the browning index, pigments, phenolic compounds and antioxidant activity, while HPLC-DAD was used for the identification and quantification of individual biflavones (amentoflavone, bilobetin, ginkgetin, isoginkgetin and sciadopitysin). The most abundant biflavonoids were isoginkgetin and bilobetin, the amounts of which exceeded 1000 µg/g dw in all leaf samples. They were followed by ginkgetin and sciadopitysin, the amounts of which were about 30% lower. The drying method did not influence biflavone content or the total carotenoids, total polyphenols and total flavonoids. Consequently, our study suggests that all three methods may be used for the preparation of yellow ginkgo leaves as a source of biflavones and other bioactive compounds. [ABSTRACT FROM AUTHOR]

Almond bagasse resulting after the production of almond-based drinks represents a promising by-product with potential for use as a functional ingredient. To facilitate its utilization, the stability of this material can be achieved through dehydration processes such as hot air drying or freeze-drying. Nevertheless, owing to its high fat content, almond bagasse is prone to lipid oxidation, which could result in undesirable quality. Therefore, the objective of this work was to assess the impact of dehydration (by hot air drying at 60 and 70 °C and by freeze-drying) and storage (at room temperature and in accelerated conditions) on the functional quality and stability of almond bagasse powder. Throughout the dehydration process, it was observed that antioxidant compounds were preserved without significant differences among dehydration treatments. These compounds increased over the storage period, especially in the samples treated with hot air. Regarding antiradical capacity, the hot-air-dried samples showed higher values than the freeze-dried ones, although in all cases, it increased during storage. For total phenols in samples air-dried at 70 °C, increases of more than 50% were observed. The acidity and peroxide index were increased in the extended storage period, although they did not reach critical values. Samples stored for 180 days showed peroxide values ranging from 10 to 12.8 meq O2/kg dry matter for samples stored at room temperature and from 14.7 to 23 meq O2/kg dry matter for samples subjected to accelerated storage. [ABSTRACT FROM AUTHOR]

The need for cost-efficient, simple and radiation free technologies in clinical diagnostics has orientated the scientific community in the investigation of techniques such as vibrational spectroscopy. Vibrational spectroscopy due to its simplicity both in sample preparation as well as friendly use combined with the technological evolution in data processing and storage could play a promising role in diagnostics even for multifactorial diseases such as osteoarthritis via biofluid analysis. However, despite the related works aiming in synovial fluid there is not a common line in terms of sample preparation. Hence, it is important to establish an effective sample pretreatment protocol to avoid subjectivity and provide the possibility of reliable comparisons among results. In this work, freeze drying preprocessing technique was compared with natural drying in terms of diagnostic performance in 35 knee synovial fluids aspirated from primary osteoarthritic patients with 2 and 4 Kellgren-Lawrence scores. Principal component analysis combined with mean spectra analysis was implemented for this diagnostic purpose. Results have shown that natural drying technique tends to generate more distinct enhanced interclass variations among synovial dried samples compared to freeze drying, despite the latest potential in other biological samples. [ABSTRACT FROM AUTHOR]

Fresh and dried Cordyceps sinensis are widely used by the public for medicinal and health purposes. However, the differences between them have not been examined. In this study, fresh wild and artificial C. sinensis (WFC and AFC) were dried to obtain dried wild and artificial C. sinensis (WDC and ADC). Non-targeted GC-MS was used to analyze the metabolic profile characteristics of the four groups of samples. The results showed that air drying significantly altered the composition and content of C. sinensis, mainly in the form of higher abundance of organic acids and derivatives and lower abundance of lipids and lipid-like molecules in fresh C. sinensis. Hierarchical cluster analysis (HCA) and quantitative analyses showed that air drying increased the abundance of Valine, Zinniol, Urocanate, Vulpinic acid, and Uridine 5'-diphosphate, and decreased Xanthotoxol, Vitexin-4-o-glucoside, Val-trp, and Wogonin. These differentially accumulated metabolites (DAMs) were also shown to be potential biomarkers for C. sinensis. KEGG enrichment analysis identified lysine biosynthesis as the most significantly enriched pathway. Annotation of these DAMs to lysine biosynthesis revealed that citrate cycle and pyruvate metabolism entered lysine biosynthesis via 2-oxohlutarate and Homocitrate, respectively, resulting in significant enrichment of L-saccharopine and L-lysine content was significantly higher. Alanine, aspartate, and Glutamate metabolism synthesized more L-aspartate to promote L-lysine synthesis. Thus, high levels of L-lysine result in lysine degradation and pymolysine, which are the most active metabolic pathways during the drying of fresh C. sinensis and indirectly lead to differences in metabolic profiles. [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.)

The main goal of this work is to study an innovative method to valorize peach peel which is the major by-product of the peach industry. Peach peel has the potential to be a food ingredient of considerate nutritional value after its drying. Although drying is one of the oldest used fruit preservation processes, there are no studies on peach peel drying. More specifically, this work focuses on the combination of ultrasounds and immersion in ethanol as a pretreatment to drying to improve the process by reducing energy consumption and ensuring a safe and high-quality product. Peach peels samples were pretreated (a) in aqueous ethanol 75% v/v for 10, 20, and 30 min and (b) in aqueous ethanol 75% v/v for 10, 20, and 30 min with simultaneous ultrasounds treatment at amplitudes of 50, 60, and 70%, and subsequently dried in a convection hot air dryer at 70°C. Mass transfer of water was described by the analytical and the simplified solution of the diffusion approach. The effect of the examined factors on drying rate and moisture diffusion coefficient was examined and the optimum conditions were determined. In addition, various properties of the dried peels (total phenolics content, total carotenoid content, ascorbic acid content, antioxidant activity, rehydration ratio, and color) were examined. The remarkable reduction obtained in the drying time (37.5%) as well as the improved dried peel characteristics achieved with the use of a suitable pretreatment for convective drying will serve a great purpose in the peach industry. [ABSTRACT FROM AUTHOR]

In this study, vacuum drying (VD), microwave drying (MW) and freeze-drying (FD) alternatives to air drying (AD) were applied to apple samples before explosion puffing drying (EPD). The volumes of AD+EPD samples were determined 20% higher than the volume of AD samples. The porosity value and the average pore radius value were obtained by examining the SEM images with the MATLAB program. Porosity values were found between 0.41-0.82 for all drying processes applied. The lowest porosity was found at 180MW, and the highest porosity was found in the FD samples. It is seen that the porosity ratio increases as the microwave power per product increases. Rehydration rates of 180, 360 and 600MW samples were determined as 308, 320 and 336%, respectively. It contributed to the increase in rehydration due to the increase in the porosity of the product with the increase in power density per product in MW drying. There was an increase in the amount of TPC with the combined use of the EPD process. The highest ABTS and DPPH were determined in the FD, FD+EPD and 600MW+EPD samples, respectively. The predrying methods and parameters described in the study significantly affected the quality of apples in terms of their physical and chemical properties. [ABSTRACT FROM AUTHOR]

Copyright of Eurasian Physical Technical Journal is the property of E.A. Buketov Karaganda University 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.)

3D cheap, lightweight and robust cellulosic parts can be obtained via extrusion of a cellulosic aqueous paste followed by air-drying. During the air-drying step, an anisotropic shrinkage occurs. The objective of this study is to characterize the macro and mesoscale phenomena occurring during the drying process. We used sub-minute laboratory X-ray microtomography during air-drying tests combined with advanced image analysis including Digital Volume Correlation to reveal the mechanisms that took place at the sample and at the filament scales. This allowed the qualitative and quantitative analysis of the structural and kinematical changes occurring during the air-drying. The macroscopic anisotropic shrinkage of the structure is associated with a decrease of the solid fraction of the cube and a decrease of the volume of the central pore, a decrease of the number and of the volume of the inter-filament and intra-filament pores, a change of the shape and dimensions of the filaments cross section. We observed delamination effects, increase of the number of inter and intra filament pores. These results complete the analysis commonly carried out at the macroscale and are necessary to build a model for the prediction of drying mechanisms of 3D printed part of cellulose and to propose more accurate compensation strategies. [ABSTRACT FROM AUTHOR]

In this study, solid olive mill waste (SOMW) was used to obtain antioxidant compounds using solid–liquid extraction. The effect of different extraction methods, namely microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), Soxhlet, and conventional solvent extraction, on the yield, total phenolics, and total antioxidant activity of SOMW extracts was investigated. Untreated and dried SOMW were subjected to extraction with water and methanol. The antioxidant activity of the extracts was evaluated using the DPPH assay, while their total phenolic content was measured using the Folin–Ciocalteu method. For the characterisation of the extracts, HPLC-DAD analysis was performed. The results showed that the extraction yield was significantly influenced (p < 0.05) by the solvent used, the material treatment prior to extraction, the moisture content of SOMW samples, and the extraction time. The optimised parameters were water, as the extraction solvent, and MAE as the extraction technique (extraction temperature of 50 °C and time of 1 h). The evaluation of the antioxidant activity of the extracts indicated that phenolics were the dominant bioactive compounds. The extracts were found to be rich in several hydroxytyrosol derivatives. Therefore, SOMW can be a valuable resource for bioactive compounds using conventional and innovative extraction techniques. [ABSTRACT FROM AUTHOR]

Recovering waste from industrial food processes and developing new healthy foods as plant protein sources has been a major focus of scientific research and industrial innovation in food. Thus, the consumption of plant-based beverages from soy, oat, or almond has been promoted. In the case of almonds, the resulting solid bagasse has an interesting nutritional profile and its transformation into a powdered product could be a valuable option for the food industry. The main objective of this work was to determine the effect of hot air drying at 60 and 70 °C and freeze-drying on the physicochemical, water interaction, emulsifying and antioxidant properties of powdered almond bagasse. Furthermore, hot air-drying curves have been modelled and isotherms at 20 °C have been performed. The proximate composition of the powder revealed a protein content of 15% and a fat content of 25%, which makes it a remarkably different powder from those obtained from other vegetable residues such as fruits and vegetables. This composition was decisive in the effect of the drying method and drying temperature, and no significant differences were observed on the physico-chemical or antioxidant properties regardless of the drying method used. However, freeze-drying resulted in a powder with a more homogeneous particle size distribution and better oil-interaction properties, especially with higher emulsifying activity and stability. [ABSTRACT FROM AUTHOR]

Elderflower extracts are known to be a source of valuable substances that show a wide spectrum of biological activity, including antibacterial and antiviral properties, which demonstrate a degree of effectiveness against SARS CoV-2. In this work, the influence of fresh inflorescence stabilisation methods (freezing, air drying, and lyophilisation) and extraction parameters on the composition and antioxidant properties of the extracts were studied. Wild elderflower plants growing in the Małopolska Region of Poland were studied. Antioxidant activities were evaluated by 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging ability and ferric-reducing antioxidant power assays. The total phenolic content was determined using the Folin-Ciocalteu method and the phytochemical profile of the extracts was analysed using HPLC. The obtained results showed that the best method for the stabilisation of elderflower was lyophilisation, and the determined optimal maceration parameters were 60% methanol as a solvent and a process time of 1–2 days. [ABSTRACT FROM AUTHOR]

Būt (Sideroxylon mascatense) is an indigenous wild blueberry found in Oman. It has a very short season and is commonly preserved by drying. The aims of this study were to determine the physico-chemical characteristics and stability of phytochemicals (i.e., polyphenols and flavonoids) in the berries during drying (i.e., freeze-drying at −40 °C and air-drying at 60 and 90 °C) and the polyphenol stability of the dried berries as a function of storage temperature (i.e., 90, 70, 60, 40, 20, and −20 °C). The moisture content of fresh berry flesh was 64.5 g/100 g sample (wet basis). The crude protein and fat contents were higher in the seeds than in the flesh. Glucose and fructose were the main sugars and their concentrations were highest in the sample air-dried at 60 °C. The initial total polyphenol content (TPC) and total flavonoid content (TFC) of the flesh were 2.009 mg gallic acid equivalent (GAE)/g dry-solids and 0.199 mg catechin equivalent (CE)/g dry-solids, respectively. The samples air-dried at 90 °C and freeze-dried at −40 °C had higher TPC (i.e., 2.638 mg GAE/g dry-solids) and TFC (i.e., 0.395 mg CE/g dry-solids), respectively. There was a significant difference between the TPC and TFC of fresh and dried wild berries (p < 0.05). The freeze-dried wild berries retained a high TPC compared to the air-dried samples. The polyphenol storage stability of freeze-dried wild berries at different storage temperatures showed two phases: an initial release phase followed by a decay phase. The polyphenol storage stability was modeled using the Peleg model and the kinetic parameters were correlated with the storage temperature. [ABSTRACT FROM AUTHOR]

In this study, Turkish lignite dried with hot air and superheated steam was experimentally investigated. Drying experiments were carried out at 120°C drying temperature and atmospheric pressure. Mass, center and surface temperature changes of lignite having a diameter of 30 mm were continuously measured. Hot air and superheated steam drying methods were compared, and it was found that, because of condensation in the initial stage of superheated steam, the moisture content of the lignite sample temporarily increased. On the contrary, the moisture content of the lignite sample dramatically reduced on drying with hot air. Six different thin-layer models describing the drying kinetics of lignite were fitted to the experimental data, with the Pusat model giving the best predictions with superheated steam drying and the Midilli model giving the best predictions with hot air drying of a single particle. [ABSTRACT FROM AUTHOR]

This study was undertaken to investigate the effect of cold plasma (CP) and ultrasound wave (US) before and during air drying of cumin seeds, respectively. In this regard, different CP exposure times (15 and 30 s), sonication powers (60, 120, and 180 W), and drying air temperatures (30, 35, and 40 °C) were practiced at the velocity of 0.6 m/s to study the underlying changes in drying time, effective moisture diffusivity, energy consumption, total color change, rupture force, and microstructure of cumin (Cuminum cyminum L.) seeds. It was found that CP pretreatment significantly increased effective moisture diffusivity and reduced drying time, energy consumption, and color change in the cold plasma–assisted drying program (CPCV). The morphological alteration in the seeds' surface, which accelerates water removal from the inner structure toward the surface, is the main cause of CP-induced modification in the drying process. The positive effect of CP pretreatment on the cumin seeds was intensified when it was followed by high-power sonication during air drying of the seeds. So that, the maximum reductions in drying time (46.65%), energy consumption (39.49%), total color change (40.69), and rupture force (46.84%) were in possession of 15 s CP pretreatment before ultrasound-assisted drying at the power level of 180 W. Longer exposure time (30 s) resulted in denser material with the compacted surface resulting in less color retention and increased rupture force. [ABSTRACT FROM AUTHOR]

Feasible utilization of superheated steam spray drying at different inlet temperatures (160–200 °C) and feed rates (3–15 mL/min) to produce instant coffee and sodium copper chlorophyllin (natural green colorant) powders was assessed. Yield, physical properties and morphology of the steam-dried powder were determined and compared with those of the air-dried one. Superheated steam spray drying might not be a proper method for producing coffee powder as at all test conditions coffee extract adhered and dried on the wall of the chamber. Superheated steam spray drying, on the other hand, has the potential to produce the color powder with smaller particle size, higher bulk density and more wrinkle surfaces, resulting in the superior solubility. Mean diameter (D[4,3]), bulk density and solubility time of the steam-dried powder were 15.53–15.97 µm, 0.67–0.68 g/cm3 and 192–226 s, while those of the air-dried powder were 29.03–31.02 µm, 0.34–0.35 g/cm3 and 244–283 s, respectively. In terms of yield and color, both of the powders and of the reconstituted solutions, no significant differences among the air-dried and steam-dried powders were observed. [ABSTRACT FROM AUTHOR]

The shrinkage of the connective tissue and myofiber of lamb meat submitted to heat treatment or air drying at different storage stages (1, 5 and 7 days) was evaluated herein. The longitudinal and transverse shrinkage of heated lamb meat was significantly influenced by storage time and water bath heating temperature (50 °C, 70 °C and 90 °C) (p < 0.001). In contrast, the shrinkage of air-dried lamb meat was not influenced by storage time (p > 0.05). The microstructure of heated lamb meat, namely, the distance between muscle fascicles, the distance between myofibril networks, the area of myofibril networks, and the endomysium circumference, was significantly influenced by storage time (p < 0.05). During storage, the proportion of muscle fibers completely detached from endomysium increased, which could be due to the progressive degradation of proteins linking the endomysium and myofibril, including β-dystroglycan, α-dystroglycan, integrin-β1, and dystrophin. However, degradation of such proteins did not influence the shrinkage of lamb meat stored for five days or longer, since the decreased distance between myofibril networks indicated a higher shrinkage ratio of the endomysium compared to myofibers in samples air-dried at 35 °C or heated at 90 °C. The effect of these proteins on the shrinkage of heated lamb meat (raw meat stored for 1 day or less time) requires further elucidation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board 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.)

In this research, Aspergillus niger inhibition with ethanol and methanol extracts of apricot leaves in cherry juice was investigated. Aspergillus niger concentration 3.5 log cfu/mL is determined in control cample (ju). Ethanolic (air-dried, microwave-dried) and methanolic (air-dried, microwave-dried) extracts (1 mL) are added to cherry juice (9 mL), separately. They were left for incubation at 25°C for 3 minutes. Then Aspergillus niger (1 mL) is put into test tubes on extracts and left for incubation at 25°C for 24 h. All extracts significantly reduced Aspergillus niger numbers in cherry juice compared to control samples. The highest inhibitory activity was detected in the sample extracted with methanol from microwave-dried apricot leaves (2.94 log cfu/mL). The effect of apricot leaves’ ethanol extract was found to be higher than methanol extract, except the samples dried in microwave. The reason for this might be that the phenolic compounds in apricot leaves are more soluble in ethanol than in methanol when they dried in air. Additionally, the heat applied in the microwave might have damaged the phenolic compounds found in apricot leaves. These results demonstrated that apricot leaves can be used for decrease Aspergillus niger in cherry juice at 25°C. [ABSTRACT FROM AUTHOR]

The incorporation of red raspberries in bakery and dairy products is limited due to the fragility of the berries. This compromises the appearance of the food product due to the bleeding of juice caused by tissue rupture. In this study, we developed vacuum-impregnated dehydrofrozen red raspberries from fresh fruit. Initially, we optimized drying and freezing conditions for red raspberries that were not vacuum impregnated using air drying alone and in combination with osmotic dehydration, followed by air blasting and cryogenic freezing methods. Later, optimal conditions of partial drying and freezing were used for raspberries that were vacuum impregnated with low methoxyl pectin (LMP) at 10 g of pectin kg−1 of solution and calcium chloride (CaCl2 · 2H2O) at 30 g of calcium kg−1 of pectin. Conditions for the vacuum impregnation of raspberries were based on our previous research. The berries were partially dehydrated using hot air (65 °C) until a final water content of 0.65 g of water g−1 of fruit was reached. Next, the berries were placed in glass jars, sealed, and cooled at 4 °C for 2 h. They were then frozen by air blasting and stored for 2 months at −35 °C prior to evaluation. The mechanical properties of the berries, including the maximum force (FM) and gradient (GC), were considered to be suitable indicators of fruit firmness. Results demonstrate that raspberries impregnated with pectin and calcium and then partially dried and frozen have higher FM and GC values than commercially frozen-thawed berries. These dehydrofrozen raspberries show improved structural integrity for use in bakery and dairy products. [ABSTRACT FROM AUTHOR]

The complexities of wood microstructure cause difficulties in understanding water movement characteristics during drying. Here, the water transport dynamics in softwood (Japanese cypress) with different sample lengths (30 mm, 60 mm, and 90 mm) and various drying temperatures (30 °C, 60 °C, and 90 °C) were studied using a rapid and high-resolution moisture content (MC) mapping method based on long-wave near-infrared hyperspectral imaging (NIR-HSI). The observations of this study are as follows: slow drying at approximately 30 °C, the area near the subsurface of the wood samples tends to have higher MC than the central parts during drying, especially in the case of longer wood samples. For drying at higher temperatures, strongly bonded water appeared at the surface areas much earlier, which could easily cause sample deformation and cracking. Overall, the experimental results suggest the capillary effects could play a major role at the first stage of slow drying at fiber level; then, the transfers between bound and free water could play a significant power source in the second drying stage. It is expected that this study will be of help in providing a basis to study and simulate the drying characteristics of cellular and hydrophilic materials. [ABSTRACT FROM AUTHOR]

The impact of air velocity and temperature on the drying curves of the invasive brown alga Sargassum muticum was evaluated. An air impingement dryer was applied at five air velocities and four air temperatures. The equilibrium moisture content was properly modeled by Oswin, Halsey, and GAB models. Fick's diffusional model was employed to identify the apparent moisture diffusivity. The variations of the diffusivity versus temperature and velocity were determined. Three semi‐empirical expressions, namely, Page, two‐term, and Henderson‐Pabis modified equations were selected to fit the drying kinetics. The two‐term equation was the most appropriate to model the experimental data. [ABSTRACT FROM AUTHOR]

The present work proposes using microencapsulation, ethanol, ultrasound and convective drying to obtain iron fortified pineapple chips. Iron microparticles were produced by ferrous sulphate encapsulation with maltodextrin by spray drying. As a hydrophilic material, microparticles were dispersed in ethanol to be incorporated into the pineapple tissue, with or without the application of ultrasound. Then, the effect of different pre-treatment times with ethanol and ethanol + ultrasound was evaluated on pineapple drying. Finally, the residue of ethanol was evaluated in the final products. Pre-treatment with ethanol and ethanol + ultrasound allowed to increase significantly the iron content of pineapple chips (up to 1000% in comparison with control). In addition, the drying time decreased from 35.4 to 51.9% with the utilization of ethanol and ultrasound. Pre-treatment for 7.5 min allowed to reduce the drying time and to achieve negligible residual ethanol in the sample. The results demonstrated that the combination of the proposed technologies can be used to obtain pineapple chips enriched in iron, with reduced time of drying and a negligible residue of ethanol. [ABSTRACT FROM AUTHOR]

Sediment humic substance (SHS) is a highly heterogeneous and complex organic mixture with a broad molecular weight range. It is the significant component that associates distribution, transport, and biotoxicity of pollutants in a river environment. Air- and freeze-drying sediment pre-treatment may cause different biological activity and may result in different chemical quantities and sediment organic matter. This study collected sediments that received livestock wastewater discharge. The sediments were air- (AD) and freeze-dried (FD). The dried sediment organic matter was extracted with an alkaline solution and separated into three size-fractioned SHS samples. Size-fractioning is an effective method used to differentiate materials, on a molecular level. The bulk solution (<0.45 μm) was designated as BHS, and size-fractioned solutions were identified as LHS (<1 kDa), MHS (1–10 kDa), and HHS (10 kDa–0.45 μm). The AD SHS had a lower dissolved organic carbon (DOC) concentration than the FD SHS for the bulk and individual size-fractioned SHS, but the AD and FD SHS had a similar distribution of organic carbon in the size-fractioned SHS. The AD SHS had higher aromaticity (SUVA254) and an extent of humification (HIX) than the FD SHS. In addition, the high molecular weight SHS (HHS) had a higher SUVA254 but lower HIX than the MHS and LHS. The HHS had significantly lower fulvic acid but had higher humic acid-like substances than the MHS and LHS. This is possibly the reason the LHS had a higher humification degree but lower aromaticity than HHS. The size-fractioned SHS and optical indicators distinguished the difference between the chemical properties when air- or freeze-dried, due to the different degree of biological activities. [ABSTRACT FROM AUTHOR]

An original drying process combining air impingement and intermittent drying was studied on apple slices and mango cubes. The influence of four operating parameters (air velocity, drying/tempering periods, upper height, and air temperature) on the drying time and on the drying rate was evaluated. Continuous and intermittent drying were compared. The intermittency α = 1/7 (τon = 10 seconds and τoff = 60 seconds) gave the best results. A time savings of 54% for apple and 67% for mango was reached. In continuous drying, a time savings of 4620 seconds was observed by increasing the air velocity from 6 to 40 m s−1 for apple. Air temperatures of 328 K for apple and of 328 K or 338 K for mango were determined as optimum to prevent case‐hardening. Experimental results were fitted with the analytical solution of Fick's second law and the modified Page equation (average values R2 = 0.985 and 0.961, for apple and mango, respectively). For both products, the apparent moisture diffusivity Dapp, the drying constant k, the drying coefficient n, and the activation energy Ea, were identified. Activation energies calculated from the analytical solution were 30.3 and 36.8 kJ mol−1 and were 25.4 and 30.0 kJ mol−1 using the modified Page equation for apple and mango, respectively. Mango has an increased temperature sensitivity and thus will need less energy for drying than apple. [ABSTRACT FROM AUTHOR]

Background and objectives: Histology is the microscopic study of cells and tissues through staining, sectioning and examining them under a microscope. Staining the histological sections is a series of technique processes undertaken in the preparation of sample tissues by staining using histological stains to highlight important features of the tissue as well as to enhance the tissue contrast to aid in the microscope study. Cytopathology provide researchers and clinicians with a relatively simple and fast diagnostic tool that is widely accepted in the scientific community. Various cytological stains are available for the diagnosis of orofacial lesions. The need of our study is to compare and assess the quality of Modified Ultra-Fast Papanicolaou in fine needle aspiration smear and fluid samples of head & neck swellings with routine Papanicolaoustain & Leishman Giemsa Cocktail stain. Methods: The present study included 30 samples from patients with Orofacial lesions. Three smears from each sample, a total of 90 smears were obtained in clean glass slides and stained with Conventional PAP, MUFP and LG Cocktail stain. Results: MUFP stain showed maximum score for all four parameters. 100% clean back ground, 83.3% well preserved cell morphology, 80% good nuclear characteristics, 76.7% Overall staining pattern. The air drying artifacts were comparatively less in MUFP stained smears because of rehydration of air dried smears with saline which also makes the MUFP stained smears superior to the LG cocktail stained and the PAP stained smears with a clean background and less air-drying artifacts. LeishmanGiemsa Cocktail stained smears were less superior to MUFP with 80% of them showing clean background, 46% showing crisp nuclear details, Followed by Conventional PAP stain. Interpretation and Conclusion: From our study it is recommended that Modified ultrafast pap stain is an excellent staining method for studying the cytology of orofacial lesions, followed by LeishmanGiemsa Cocktail and Conventional Pap stain. [ABSTRACT FROM AUTHOR]

Real-time monitoring of the dynamic state of water molecular structure in lignocellulosic material is challenging, but important for both theoretical studies and industrial applications. In the present study, three typical wood samples which have a fundamental difference in the anatomical structure were scanned in the near-infrared spectral range, and images were acquired from wavelengths of 1002–1847 nm during drying. Then, partial least squares regression was used to determine the water content by mass, and principal component analysis was utilized to characterize the variance of NIR difference spectral data between 1340 and 1610 nm after baseline correlation for showing the distribution changing from free water to bound water during air drying. It was clarified that the PC1 loading mainly correlates with simple water content by mass, whereas the PC2 loading contains information about water–wood hydrogen structure interactions. The three loading curve peaks of PC2 could be correlated with free, weakly bound, and strongly bound water based on longer wavelength shifting. Finally, PC1 and PC2 scores were comprehensively applied to show the distribution changing from free water to bound water in each wood sample with a 62.5 μm/pixel high spatial resolution. [ABSTRACT FROM AUTHOR]

The aim of this work is to establish a comparative investigation of the effect of different drying processes: microwave dehydration (100–600 W), air drying (40–60 °C) and infrared drying (40–60 °C) on drying kinetics and on the main quality attributes (color, total phenols and flavonoids contents, water and oil retention capacities) kinetics' of lemon (Citrus limon. v. lunari) peels. The experimental drying kinetics' of lemon peels were fitted to nine thin layer drying models. The Midilli and Kucuk model showed a better fit to experimental drying data for the three drying processes. Microwave drying at 450W preserved the maximum phenols (1.855 ± 0.016 g CAE/100 g DM) and flavonoids (0.802 ± 0.072 g RE/100 g DM) contents respectively. An increase of phenol content was noticed after 9, 13 and 14 min of microwave drying at 600, 450 and 300 W and after 156, 102 and 54 min of infrared drying at 40, 50 and 60 °C. A first-order kinetic model adequately fitted, at the beginning of drying processes, the change of total phenols and flavonoids contents. Total color difference (ΔE) increased progressively with increasing drying time and temperature or microwave power level. ΔE showed a zero-order model whatever the applied drying process. Water retention capacity (WRC) of dried lemon peels decreased during drying processes. However, infrared and microwave drying increased the oil retention capacity (ORC) of lemon peels. The WRC and ORC followed first-order kinetics during air drying and a second order polynomial model during microwave and infrared drying processes. [ABSTRACT FROM AUTHOR]

Intensification of large-scale urea production is an urgent task. One of the factors restraining the increase in urea production is the insufficient performance of the granulation tower, in which outside air is supplied from below to cool the freely falling drops of urea alloy. Three methods of preparation of air supplied to the lower part of the granulation tower are considered. It is shown that the first two methods cannot significantly increase the tower productivity. The third method has great capabilities, in the implementation of which air cooling is organized in a hollow nozzle water scrubber. With this approach, it is also possible to significantly reduce the dimensions of the heat exchanger-evaporator, since it can be installed on the stream of water circulating in the scrubber, and not on the air stream. Calculations have been made for three options for air supply to the granulation tower, which differ from each other in the conditions of air intake in front of the K-664A (or K-664V) pressure axial fan. The first option meets the summer operating conditions of the tower, when the outside air temperature is 35 °C. The second option corresponds to normal operating conditions at an air temperature of 20 °C. When using the third option, it was assumed that the temperature of the air processed in the scrubber decreases from 35 to 7 °C. The calculations were carried out taking into account not only the changing temperature and relative humidity of the outside air, but also the supply of heat to the processed air, which is equivalent to the power of the forced fan. The conditions of heat exchange between heated air and cooled urea in the fluidized bed apparatus were taken into account. The performed calculations allow using the aggregated machine WOC-100 manufactured by «McQuay» (USA) for air cooling with two centrifugal compressors operating on R134a. When the granulation tower operates according to the second option, when in hot weather (May-October) air is supplied to it, cooled in a scrubber to 20 °C, approximately 40,000 tons of granular urea can be produced additionally. [ABSTRACT FROM AUTHOR]

Supersonic separators (3Ss) are applied in gas separation processes. Two‐dimensional simulation is employed to investigate the effect of operational and thermophysical parameters on the shockwave position. In addition, the impact of the cyclonic part and wet outlet geometry is evaluated by proposing four cases. Increasing the length of the cyclonic part exerts positive and negative influences on the performance of the 3S and the pressure recovery coefficient, respectively. The optimum length is determined between 10 and 15 cm. To demonstrate negative effects of wasted air from the wet outlet, its flow has been increased from 3.6 to 8.1 % of the inlet flow. Improved performance of the 3S is obtained by reducing the flow disturbances around the wet outlet and moving the shockwave towards the outlet. [ABSTRACT FROM AUTHOR]

Ginger rhizome (Zingiber officinale) is widely used as a spice or as a medicinal plant. The major bioactive compound in fresh ginger rhizome is 6-gingerol and it is known for having a number of physiological effects. This compound is heat-sensitive and during cooking or drying will transform into 6-shogaol. Hence, the 6- gingerol content is used to evaluate the quality of dried ginger. The content of 6-gingerol during drying was measured using HPLC. Several factors that could affect the 6-gingerol content were considered and a predictive model for changes in 6-gingerol has been developed from the experimental data. The predictive model includes a single term drying model that predicts the changes of moisture content during drying. Drying time and relative humidity (ranging from 10% to 40%) impacted 6-gingerol content whereas drying air temperature (ranging from 30°C to 60°C) had a lesser effect. It was also found that the 6-gingerol content in fresh rhizomes was highly variable and thus required thorough testing prior to drying to be able to make the prediction more accurate. [ABSTRACT FROM AUTHOR]

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department 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.)

The aim of this work was to review the studies that evaluated the effect of drying temperature on the content of ascorbic acid (AA), total phenolic (TPC), and total flavonoid contents (TFC) in fruits and vegetables, and quantify whether drying at 40 °C is more favorable than at higher temperatures. For the purpose of this study, AA, TPC, and TFC values for 40 °C were compared with those obtained at 50 °C, 60 °C, and 70-80 °C. A meta-analysis was performed using the weighted response ratio calculated for each experiment. Despite the fact that other variables significantly influenced the nutrient content in individual experiments, the meta-analysis provided a general view on the effect of air-drying temperature on the quality of plant-based food products from outcomes of various studies. [ABSTRACT FROM AUTHOR]

Copyright of Revista Facultad Nacional de Agronomía Medellín is the property of Universidad Nacional de Colombia 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.)

The aim of this research was to evaluate the effect of different drying methods on industrially obtained lingonberry pulp juice by-products. For investigations, by-product was dried using hot air dryer (at temperatures 80 °C, 60 °C and 40 °C), microwave-vacuum dryer and freeze-dryer. The freshly defrosted by-product was used as control. All samples were analysed on the basis of their moisture content, colourimetric attributes (C1E L*a*b* colour system), content of vitamin C (iodometric method), content of total carotenes (TC), total phenol content (TPC). total anthocyanin content (TA) and antiradical activity (DPPH, ABTS+). The obtained data on content of vitamin C showed a 10% decrease between control and sample dried in hot air at 80 °C. Similar changes were noticed with total anthocyanin content, the lowest amount was also foiin in this sample (306.72 ± 18.32 mg 100 g-1 DW). Total carotenes content was higher in freeze-dried sample (5.61 ± 0.16 mg 100 g-1 DW) which was very close to control sample. A significant loss of total phenol content was noticed after drying, up to 80%, similar tendencies were noticed with changes of antiradical activity'. After evaluating the obtained data, the use of hot air dryer at 80 °C temperature resulted in the lowest amount of vitamin C and anthocyanins in lingonberry by-products, which makes this method unsuitable for drying byproducts of these berries. However, vacuum assisted microwave drying and freeze drying showed less dama 21112 impact on dried material. [ABSTRACT FROM AUTHOR]

The content of essential oil components of aromatic plants diminishes at temperatures over 30 °C. Accordingly, in order to minimize the loss of volatile compounds, plant drying is usually performed at temperatures below 50-60 °C. Aspects related to air convective drying (50 °C) of fixed-bed jasmine flowers coupled with recovery of volatile compounds from the effluent of drying column by fixed-bed adsorption (30 °C) onto activated carbon were presented in this paper. The performances of drying and adsorption processes were measured and predicted at different values of air superficial velocity (0.12-0.30 m/s). Activated carbon adsorption capacity was up to 0.2 kg/kgAC, whereas drying and adsorption rates were up to 0.0065 kg/(kgwm·min) and 0.0035 kg/(kgAC·min), respectively. [ABSTRACT FROM AUTHOR]

Prunes are generally produced by drying fresh plums with a stream of hot air. Changes in various quality indicators, such as bulk density of foodstuffs, have substantial impact on the performance of drying processes. Optimization of bulk density is, therefore, a requirement for development and perpetuity of drying technologies. The aim of this study was to investigate the effect of ultrasound-assisted osmotic dehydration pretreatment on bulk density of Mirabelle plum at various operating conditions (sonication time, concentration of osmotic solution and immersion time in the osmotic solution). Results showed that application of ultrasound-assisted osmotic dehydration, compared to control sample, led to a significant (p < 0.05) increase in bulk density from 1.33 to 9.90 %. Experimental data of bulk density variations versus dimensionless moisture content were well fitted to an empirical power model with high R. [ABSTRACT FROM AUTHOR]

The yeast form (blastospore) of the dimorphic insect-pathogenic fungus Beauveria bassiana can be rapidly produced using liquid fermentation methods but is generally unable to survive rapid dehydration processes or storage under non-refrigerated conditions. In this study, we evaluated the influence of two convective drying methods, various modified atmosphere packaging systems, and storage temperatures on the desiccation tolerance, storage stability, and virulence of blastospores of B. bassiana ESALQ 1432. All blastospore formulations were dried to <5 % water content equivalent to a < 0.3. The viability of B. bassiana blastospores after air drying and spray drying was greater than 80 %. Vacuum-packaged blastospores remained viable longer when stored at 4 °C compared with 28 °C with virtually no loss in viability over 9 months regardless the drying method. When both oxygen and moisture scavengers were added to sealed packages of dried blastospore formulations stored at 28 °C, viability was significantly prolonged for both air- and spray-dried blastospores. The addition of ascorbic acid during spray drying did not improve desiccation tolerance but enhanced cell stability (∼twofold higher half-life) when stored at 28 °C. After storage for 4 months at 28 °C, air-dried blastospores produced a lower LC and resulted in higher mortality to whitefly nymphs ( Bemisia tabaci) when compared with spray-dried blastospores. These studies identified key storage conditions (low a and oxygen availability) that improved blastospore storage stability at 28 °C and will facilitate the commercial development of blastospores-based bioinsecticides. [ABSTRACT FROM AUTHOR]

The effects of the drying temperature and the residual moisture content on the drying behavior, energy consumption and quality of dried citrus peels (CPs), which are value-added food ingredients, were studied. The CP samples were dried in a laboratory-scale hot-air dryer at air temperatures from 40 to 70 °C under a constant air velocity of 1 m/s until the desired moisture content for safe storage was reached or until the final moisture level was achieved for the specific drying conditions. Cakes prepared from blends containing different proportions (0 %, 10 %, 15 % and 20 %) of dried CPs were also evaluated for chemical composition and sensory attributes. The optimal drying temperatures were 50-60 °C, and the optimal moisture content was 10±0.2 % w.b.; these conditions reduced the drying time and energy consumption and maximized the product quality. In contrast, over-drying CPs with the higher temperatures and to a final moisture level of 5.4±0.2 % sharply increased the loss of vitamin C, carotenoids as antioxidants and essential oils. Incorporation of 15 % dried orange and mandarin peels in cake formulas increased the dietary fiber by 33.5 % and 29.6 %, the crude fat by 2.9 % and 4.6 % and the ash by 30.6 % and 29.0 %, respectively, whereas the protein and total carbohydrate content decreased slightly. Highly acceptable nutritious cakes could be obtained by incorporating 15 % orange or mandarin peel dried to 10 % w.b. moisture content into the formulation. [ABSTRACT FROM AUTHOR]

Airborne particulate matter (PM) has been included among the most important air pollutants by governmental environment agencies and academy researchers. The use of terrestrial plants for monitoring PM has been widely accepted, particularly when it is coupled with SEM/EDS. Herein, Tillandsia stricta leaves were used as monitors of PM, focusing on a comparative evaluation of Environmental SEM (ESEM) and High-Pressure SEM (HPSEM). In addition, specimens air-dried at formaldehyde atmosphere (AD/FA) were introduced as an SEM procedure. Hydrated specimen observation by ESEM was the best way to get information from T. stricta leaves. If any artifacts were introduced by AD/FA, they were indiscernible from those caused by CPD. Leaf anatomy was always well preserved. PM density was determined on adaxial and abaxial leaf epidermis for each of the SEM proceedings. When compared with ESEM, particle extraction varied from 0 to 20% in air-dried leaves while 23-78% of particles deposited on leaves surfaces were extracted by CPD procedures. ESEM was obviously the best choice over other methods but morphological artifacts increased in function of operation time while HPSEM operation time was without limit. AD/FA avoided the shrinkage observed in the air-dried leaves and particle extraction was low when compared with CPD. Structural and particle density results suggest AD/FA as an important methodological approach to air pollution biomonitoring that can be widely used in all electron microscopy labs. Otherwise, previous PM assessments using terrestrial plants as biomonitors and performed by conventional SEM could have underestimated airborne particulate matter concentration. [ABSTRACT FROM AUTHOR]

Copyright of Tropical Grasslands / Forrajes Tropicales is the property of International Centre for Tropical Agriculture - CIAT 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.)

The purpose of this research was to develop an approach for porosity estimation in the process of convective air drying. Fresh apple slices were exposed to 80°C drying to equilibrium moisture content 0.2 g/g. Porosity at different stages of drying was estimated using three approaches: (1) direct volume and mass measurements, (2) pycnometer measurements, and (3) theoretical model. All three approaches were in good agreement in the range of moisture contents above 1.0 g/g. However, at moisture contents below 0.26 g/g, significant deviation of pycnometer measurements from both experimental estimates and theoretical model was observed. This difference could be explained by transformation of open pores into closed pores due to glass transition phenomenon. This study presents an example of separate quantitative estimation of total, open-, and closed-pore porosity. [ABSTRACT FROM PUBLISHER]

Convective drying in hot air is still the most popular method applied to reduce the moisture content of fruits and vegetables. Conventional hot-air drying of Mirabelle plum is considered to be a slow and energy intensive process. This is due to the fact that the waxy skin of Mirabelle plum has low permeability to moisture, a fact which results in high shrinkage. The aim of this study was to investigate the effect of ultrasound-assisted osmotic dehydration pretreatment on shrinkage of Mirabelle plum as a function of moisture content with the end goal of optimizing operating conditions that minimize shrinkage of the produce during drying. Results showed that application of ultrasound-assisted osmotic dehydration led to a significant (p< 0.05) decrease in shrinkage (from 76.41 to 64.05%). A linear relation between moisture loss and shrinkage was observed. Results indicated that shrinkage may be easily estimated from changes in moisture content, and independent of the drying rate. Inversely, determination of shrinkage would provide an indirect indication of moisture content. [ABSTRACT FROM PUBLISHER]

Domestic food waste drying foresees the significant reduction of household food waste mass through the hygienic removal of its moisture content at source. In this manuscript, a new approach for the development and optimization of an innovative household waste dryer for the effective dehydration of food waste at source is presented. Food waste samples were dehydrated with the use of the heated air-drying technique under different air-drying conditions, namely air temperature and air velocity, in order to investigate their drying kinetics. Different thin-layer drying models have been applied, in which the drying constant is a function of the process variables. The Midilli model demonstrated the best performance in fitting the experimental data in all tested samples, whereas it was found that food waste drying is greatly affected by temperature and to a smaller scale by air velocity. Due to the increased moisture content of food waste, an appropriate configuration of the drying process variables can lead to a total reduction of its mass by 87% w/w, thus achieving a sustainable residence time and energy consumption level. Thus, the development of a domestic waste dryer can be proved to be economically and environmentally viable in the future. [ABSTRACT FROM PUBLISHER]

A novel drying method for frozen-thawed whole cranberries was developed by combining microwave osmotic dehydration under continuous flowmedium spray (MWODS) conditions with microwave vacuum finish-drying. A central composite rotatable design was used to vary temperature (33 to 67 °C), osmotic solution concentration (33 to 67 °B), contact time (5 to 55 min), and flow rate (2.1 to 4.1 L/min) in order to the determine the effects of MWODS input parameters on quality of the dried berry. Quality indices monitored included colorimetric and textural data in addition to anthocyanin retention and cellular structure. Overall it was found that the MWODS-MWV process was able to produce dried cranberries with quality comparable to freeze dried samples in much shorter time. Additionally, cranberries dried via the novel process exhibited much higher quality than those dried via either vacuum or convective air drying in terms of color, anthocyanin content, and cellular structure. [ABSTRACT FROM AUTHOR]

Background: Studies regarding the effect of various methods to increase the surface hardness of Type IV dental stone are not conclusive. Therefore, this study was carried out to evaluate the effect of air drying, micro oven drying and die hardener on surface hardness of Type IV dental stone. Materials and Methods: A standard metal die was fabricated; polyvinyl siloxane impression material was used to make the molds of metal die. A total of 120 specimens were obtained from two different die stones and were grouped as Group A (kalrock) and Group B (pearl stone), and were subjected to air drying for 24 h, micro oven drying and application of die hardener. These models were then subjected to surface hardness testing using the knoop hardness instrument. The obtained data were subjected to statistical analysis. Results: The hardness of Group A specimens was 64 ± 0.54 Knoop hardness number (KHN) after application of die hardener, 60.47 ± 0.41 KHN after 24 h air drying, 58.2 ± 0.88 after microwave oven drying and 24.6 ± 0.4 after 1 h air drying. The hardness of Group B specimens was 45.59 ± 0.63 KHN after application of die hardener, 40.2 ± 0.63 KHN after 24 h air drying, 38.28 ± 0.55 KHN after microwave oven drying and 19.91 ± 0.64 KHN after 1 h air drying. Conclusion: Group A showed better results than Group B at all times. Application of the die hardener showed highest hardness values followed in the order by 24 h air drying, microwave oven drying and 1 h air drying in both groups. The study showed that air drying the dies for 24 h followed by application of a single layer of the die hardener produced the best surface hardness and is recommended to be followed in practice. [ABSTRACT FROM AUTHOR]

This work deals with instant controlled pressure drop (DIC)-assisted dehydrofreezing process as an innovative preservation method. Its objective was to assess the impact of combined unit operations (air drying-DIC treatment-freezing/thawing) on apple firmness. Golden delicious apple samples with initial water content ( W) of 700 % dry basis (db) were subjected to air drying reaching different W values (200, 166, 115, 64, 30 % db). Then, these partially dried samples were DIC-treated at different conditions following a design of experiment (DoE). Treated samples were frozen at −30 °C and thawed at 4 °C overnight. Values of firmness defined as puncture rupture force were used to define the textural impacts of different operations of partial air drying-DIC treatment-freezing/thawing. The results showed that the lower is the apple water content (between 200 and 30 % db), the higher is the firmness. DIC treatment had insignificant effect on firmness. Conversely, great firmness decrease was perceived for freezing/thawing of fresh and high water content samples (>200 % db). However, this freezing effect disappeared, and the firmness kept constant once the water content was lower than 166 % db. This 'freezing critical level' was obtained at higher level (200 % db) for DIC-treated samples. DoE and response surface methodology (RSM) confirmed that water content was the most influencing DIC operative parameter in terms of apple firmness. [ABSTRACT FROM AUTHOR]