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Abstract This study investigated the impact of drying temperature on the physicochemical and mechanical properties of banana pseudostem fibers sourced from the Cordoba region in Colombia. Banana fibers (BFs) were extracted through mechanical decortication from the banana pseudostem (BP) of the plant and subsequently oven-dried at temperatures of 40 °C and 90 °C. Six mathematical models were employed to analyze the drying behavior of the fibers. The density of the BFs was determined using the apparent density method, and their chemical composition was evaluated via bromatological analysis. Fiber diameter was measured using optical microscopy (OM). The BF samples were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG), contact angle measurements, and tensile testing. The results indicated that noncellulosic materials were removed from the fibers when dried at 90 °C, as evidenced by alterations in thermal degradation and fiber surface morphology observed through TG and SEM, suggesting a reduction in lignin content. While drying temperature did not affect fiber stiffness or ductility, a correlation with fiber diameter was noted. Thinner fibers, ranging from 148 to 250 μm, exhibited increased tensile strength and Young’s modulus, attributed to a more compact microfibril arrangement.

This study was conducted in the summer of 2021 to evaluate and validate the gravimetric soil water content measurements using a field oven. Ten soil types with a salinity of saturated paste (ECe) less than 4 dS m-1 and three saline soils were studied around Urmia Lake. Plots with dimensions of 1 m × 2 m were prepared for the selected soils to measure gravimetric soil water content and soil physical and chemical properties. The gravimetric water content (θm) values measured using the field oven (i.e., θmFO), were compared with those measured by a standard lab oven (i.e., θmLO). The soil water content values measured in the lab, regarded as a benchmark, were measured at 105 °C for 24 h. Temperatures of 120, 140, and 160 °C with three durations of 10, 15, and 20 min were used to dry the soil samples in the field oven. There was very good compatibility between the values of θmFO and θmLO when the soil samples were dried in the field oven for 15 or 20 min at all three temperatures. Significant linear relations were obtained between the θmFO and θmLO values as the slopes of linear relations were close to 1, the intercepts of relations were negligible and the distributions of measured data around the line 1 to 1 were unbiased. The minimal effects of soil organic matter content, clay content, salinity, and bulk density on water content measurements by the field oven indicate an important advantage of this method. These results confirm the high efficiency of the field oven for fast and reliable measurements of water content in different soils.

Renewable energy is one way to deal with the scarcity of fossil energy. Biobriquette is an alternative energy that can be used as a substitute for fuel. This research aims to determine the characteristics of each variation of biobriquettes, namely moisture content, ash content, volatile matter content, bound carbon content, calorific value, and combustion test. The raw material is sawdust of Sungkai wood (Peronema canescens Jack) with carbonization method at 300 oC for 1 hour. This study used an experimental method by varying the sawdust weight of 8.7 g, 17.4 g, 26.1 g, 34.8 g with a ratio of 2:1 for each raw material and adhesive used lubricant oil. In addition, the drying temperature of the briquettes is also varied by 80 oC (A) and 100 oC (B). Biobriquettes 4B had the best moisture content and ash content with the lowest levels of 5.98 % and 1.54 %, respectively. The levels of volatile matter and fixed carbon levels are closest to Energy and Mineral Ministry Regulation Number 47 of 2006 (PERMEN ESDM) namely 4A briquettes of 59.44 % and 1B briquettes with a content of 31.57 %. Almost all samples met the standard for calculating the calorific value of Energy and Mineral Ministry Regulation Number 47 of 2006 (minimum 4400 cal/gr) with a the result of 4512-4850 cal/gr. The ignition time of all samples was in the range of 9.67-17.9 seconds, it is faster than the ignition time of coal in the range of 286 seconds. The fastest burning time was sample 3B with a time of 19.83 minutes and the longest was sample 4A with a time of 38.95 minutes. The briquettes that had the best performance in boiling 100 ml of water were 4B briquettes with a burning temperature of 462.3 oC, a burning rate of 0.4501 and a boiling time of 2.48 minutes.

The objective of this study is mainly to analyze the drying kinetic parameters, effective diffusivity, and thermodynamic performance indicators (energy, exergy, heat, and mass transfer coefficients) of tea under different drying conditions of different drying temperatures (DT) and thin layer thicknesses (TT). Experimental drying was conducted at drying temperatures of 70°C, 80°C, and 90°C with thin layer thicknesses of 10 mm, 15 mm, and 20 mm. The results show that a higher drying temperature and a lower thin layer thickness can increase evaporation moisture content and shorten drying time. By evaluating and comparing the fitting of five drying models adopted by the coefficient of determination (R2) and chi-square (χ2), it can be found that the logarithmic model is the best to describe drying behavior. The effective moisture diffusivity shows a positively correlated trend with the increase in DT and TT, with the value of activation energy ranging from 14.030 to 22.344 kJ mol−1 K−1. The specific moisture evaporation rate (SMER), energy efficiency, exergy efficiency, and sustainability index (SI) descend as the TT increases at all DT; the specific energy consumption (SEC) and improvement potential (IP) rate perform in an opposite manner, but the TT remains unchange. The conclusion drawn from the thermodynamic parameters is opposite to the aforementioned. As the TT increases, the heat and mass transfer coefficients show a significant decrease trend. In addition, the heat and mass transfer coefficients are given as functions of DT and TT, and further knowledge shows that the mass transfer coefficient is positively correlated with DT but the heat transfer coefficient is negatively correlated. In conclusion, this article provides new insights into the effects of drying characteristics, energy consumption characteristics and heat and mass transfer characteristics in the process of tea drying under different drying conditions, and provides certain theoretical reference bases for promoting the optimization of industrialized tea drying production machinery design and drying process optimization.

This study focused on drying moringa leaves using a cabinet dryer. The impact of the 40, 50, and 60 °C drying air temperatures on the moisture content of the leaves at a constant air velocity with variation in weight (40, 80, and 120 g) was considered. Ten drying models were fitted to the drying data to describe the drying parameters of moringa leaves. The best model was chosen based on the highest coefficient of determination (R2), and the lowest sum of square error (SSE) and root mean square error (RMSE) values. The Henderson and Pabis model best described the drying characteristics of the moringa leaves having the highest R2 (0.9888) and lowest SSE (0.0401) and RMSE (0.0604). The effective moisture diffusivity increased with the temperatures ranging from 8.72 × 10-9 to 1.40 × 10-8 m2.s-1. The activation energy ranged from 90.4636, 40.4884, and 22.7466 KJ.mol-1 for 40, 80, and 120 g, respectively.

In this study, the drying of bitter gourd slices with a halogen dryer was done at different thicknesses of bitter gourd (3, 5, and 7 mm) and temperatures (60, 65, and 70 °C). The effect of varying drying characteristics in the experiment was explored. Experimental results were evaluated based on the drying time and moisture content. The results indicate that the material drying thickness and drying temperature significantly impact the drying time and the equilibrium moisture content. Furthermore, the Multivariate Adaptive Regression Splines (MARS) model is also used to train and predict the moisture content of bitter gourd in this research. The temperature, thickness of the bitter gourd, and drying time were used as input parameters for the model. Two measures R2 and Root Mean Ssquare Error (RMSE) were used to determine the accuracy of the trained MARS model. During training, the values of R2 and RMSE obtained were 0.9846 and 3.7324, respectively. The test of trained MARS was successful, with a satisfactory correlation between experimental data points and predicted points. The results show that MARS can accurately predict the moisture content of bitter gourd in a halogen dryer.

Sodium alginate (SA)–purple sweet potato peel extracts (PPE) from industrial waste indicator films were developed at different drying temperatures (25, 30, 35, 40, 45, 50, and 55 °C). The effects of drying temperatures on the film’s structural, physical, and sensitive properties were investigated. On the structural properties, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction indicated that compactness, intermolecular interactions, and crystallinity of indicator films were improved at a lower drying temperature. On the physical properties, with the drying temperature increasing, elongation at the break increased significantly (p < 0.05); ΔE and water-vapor permeability decreased significantly (p < 0.05); and thickness and tensile strength initially increased significantly (90.46 → 98.46, 62.99 → 95.73) and subsequently decreased significantly (98.46 → 71.93, 95.73 → 55.44) (p < 0.05), with the maximum values obtained at 30 °C. On sensitivity, the corresponding colors of the films became lighter as the drying temperature increased, and the films exhibited relatively excellent pH and NH3 sensitivity, with easily discernible color changes at lower temperatures. The results of this paper revealed that the overall film characteristics are improved at lower drying temperatures, which will provide valuable references for selecting the drying temperature for preparing indicator films as a guide for industrialized production.

Lithium-ion battery pack performance, safety, and lifespan are significantly influenced by temperature, yet little research has focused on the specific effects of temperature during the drying phase in paint booths. This study aims to analyse how drying temperatures affect battery modules compared to operational conditions (e.g., driving, charging) and to analyse the influence of the battery state of charge on the temperature reached by the traction battery during the drying phase. Various temperature measurement methods, including diagnostic equipment and thermocouples, were employed to conduct tests. Results indicate that the battery pack temperature during the drying phase remains below 60 °C. Comparisons with temperature measurements in other scenarios (e.g., charging, high-temperature parking) show significantly higher temperatures, highlighting the relatively low impact of paint booth drying temperatures on battery thermal management.

Waterborne coatings present a green alternative to solvent-borne coatings as only a small amount of organic solvent is released into the environment during drying. However, for waterborne coatings, the drying process is much more challenging due to the slow evaporation of water. In this work, the influence of drying temperature on the protective properties of a waterborne acrylic coating was studied. Its performance in corrosion protection of bronze substrates, representing the bronzes used for the sculptures placed outdoors, was examined. Corrosion properties were evaluated by linear polarization measurements and electrochemical impedance spectroscopy during three-week exposure to artificial acid rain solution. It was found that drying at ambient temperature resulted in modest corrosion protection, while drying at 55 °C ensured greater initial corrosion resistance, which gradually degraded during exposure to acid rain solution accompanied by the coating blistering. Drying of one-layer coating at 40 °C resulted in the formation of clearly visible corrosion products. If the coating was applied in three layers, the drying process was more efficient, leading to slightly higher polarization resistance values without visible corrosion at the bronze surface. Furthermore, the studied waterborne acrylic coating provided good corrosion protection of patinated bronze surfaces. Additionally, it was found that for efficient corrosion protection, it is preferable that the coating contains a corrosion inhibitor in order to avoid substrate corrosion during coating drying. When applied properly, studied coating does not alter the state of surfaces, both bare and patinated, which is important for its application in bronze cultural heritage protection.

In this study, the volatile profile and taste properties of Flammulina velutipes root dried at room temperature, 40, 50 or 60 ℃ were analyzed by using an electronic nose (E-nose), an electronic tongue (E-tongue), and headspace solid-phase microextraction followed by gas chromatography-mass spectrometry (HS-SPME-GC-MS). Results indicated that the drying temperature markedly affected the contents of free amino acids, soluble proteins, crude polysaccharides and 5’-nucleotides, and the overall quality of F. velutipes root dried at 50 ℃ was best. Significant differences among all dried samples were observed. Principal component analysis (PCA) combined with the E-nose and E-tongue radar charts as well as the GC-MS fingerprint could clearly discriminate all dried samples. The results obtained from hierarchical cluster analysis (the Euclidean distance was 6.5) were in agreement with those of PCA. These findings may provide theoretical support for the dehydration of edible mushrooms and other similar thermo-sensitive agricultural products.

Pengeringan bertujuan untuk mengurangi kadar air sehingga dapat meningkatkan daya tahan dan kualitas bahan pakan terutama jagung. salah satu metode pengeringan yang dapat digunakan yaitu pengeringan lapis tipis. Metode ini dapat menghilangkan air atau pelarut dari lapisan tipis bahan yang diterapkan pada suatu permukaan, sehingga tujuan dari penelitian ini adalah untuk mengetahui pengaruh pengeringan lapis tipis pada jagung (kadar air, moisture ratio, dan laju pengeringan) sebagai bahan pakan dengan tingkat suhu pengeringan yang berbeda-beda yaitu pada suhu 50, 60 dan 70 °C. Kadar air konstan yang diperoleh pada pengeringan suhu 50 °C mencapai 22.92%, pada suhu 60 °C mencapai 21.58%, sedangkan pada suhu 70 °C mencapai 17.58%, namun kadar air yang dihasilkan pada penelitian ini belum memenuhi standar kadar air yang dibutuhkan dalam penyimpanan bahan pakan (14%). Semakin tinggi suhu pengeringan yang digunakan maka akan semakin singkat proses pengeringannya dan pengurangan air bahan akan semakin cepat, mengakibatkan nilai Ln MR semakin menurun. Pada suhu pengeringan 50 °C diperoleh nilai rata-rata Ln MR= -2.4796 (R2=0.969), suhu 60 °C diperoleh nilai Ln MR= -2.7369 (R2=0.951), sedangkan pada suhu 70 °C dengan rata-rata Ln MR= -4.2102 (R2=0.977). Pada laju pengeringan pada suhu 60 °C lebih rendah dibandingkan dengan suhu 70 °C yaitu berkisar 0.44 gram/jam, sedangkan laju pengeringan pada suhu 70 °C yaitu mencapai 0.73 gram/jam. Dari hasil uji statistik dari ketiga level suhu pengeringan menunjukkan bahwa estimasi intercept tidak signifikan secara statistik pada level signifikansi 0.05.

A series of methods such as the high performance liquid chromatography and amino acid analyzer were used to study the effects of different drying temperatures (60, 75, 90 and 105 ℃) on the protein, amino acids, fatty acids and other quality components of ziziphi spinosae folium insect tea (ZSIT). The results showed that polyphenols and total amino acids of ZSIT dried at 90 ℃ with the highest total flavonoids and essential amino acids were significantly higher than those of other groups (P

Various drying temperatures impact the texture of pasta and cause different drying defects. These by-products could reflect techno-functional characteristics which are suitable for cereal products. This research addresses the influence of low (LT) and high (HT) drying pasta defects with two granulations on the theoretical and functional characteristics of hard dough biscuits. By shifting from a LT to HT drying temperature, a higher onset and peak temperature was found due to the higher mobility of starch molecules with increasing crystalline stability. The lowest transition enthalpy of biscuit formulation was also observed for higher incorporation of fine HT pasta regrinds. The algebraic model of dough with consistography determined the poor-extensible gluten and a high resistance with a greater value of P/L and P indices for LT regrinds. Scanning electron microscopy revealed a heavy and dense texture with immersed starch granules for additional fine regrinds while coarse samples caused swell granules with greater diameter. Moreover, fine HT regrinds reflected the lowest L* value for biscuit due to heat gradient tension with the hard milling process which leads to protein denaturation with decreasing nitrogenous.

The compressor speed, expansion valve opening and drying temperature are critical to the thermal performance improvement and control logic optimization of the closed heat pump drying (CHPD) system. This paper investigates the effects of the three parameters on the thermal performance of the CHPD system by the single factor experiment method. According to the experimental findings, as the compressor speed of the system increased, the heating capacity grew by 11.4%, but the coefficient of performance (COP) declined by 41.3%. As the expansion valve opening of the system increased, the heating capacity and COP grew by 73.5% and 82.9%, respectively. As the drying temperature of the system rose, the heating capacity grew by 3.1%, but the COP dropped by 25.3%. It can be concluded that reducing the compressor speed and drying temperature, and increasing the expansion valve opening could effectively enhance the thermal performance of the CHPD system.

We evaluated the antioxidant and neuroprotective potentials of extracts of Hibiscus sabdariffa calyx in Wistar albino male rats injected intraperitoneally with aluminium chloride at a dose of 7 mg/kg/day. Phytochemical screening of H. sabdariffa calyx show that coumarin glycosides and steroid were absent after drying at 50 oC. At 30 oC, there were significant (p

Binahong leaves are a plant that contains antioxidant compounds so that can be used as herbal drinks. Stevia leaves can be used as a sweetener with antioxidant compounds that can improve the taste of herbal drinks. This study aims to determine the effect of variations in drying temperature and herbal drink formulations in physical characteristics of color, chemistry including moisture content, phenol total, and antioxidant activity, as well as sensory parameters including color, smell, taste, and overall. Besides knowing the best treatment of variations in drying temperature and herbal drink formulation. This study used a Factorial Completely Randomized Design (FCRD) with two factors, namely variations in drying temperature and formulation. The drying temperature used were 55 °C, 60 °C, and 65 °C, while the binahong leaves : stevia leaves formulation used were 87.5 % : 12.5 %; 75 % : 25 %; and 62.5 % : 37.5 %. Based on the results of this study, it was found that the physical, chemical, and sensory characteristics can be influenced by the treatment of variations in drying temperature and herbal drink formulations. The best treatment for herbal drinks with variations in drying temperature and the formulation used was drying at 55 °C with the binahong leaves : stevia leaves formulation is 62.5 % : 37.5 %. The resulting characteristics are: brightness (L*) 39.605; reddish (a*) -2.307; yellowish (b*) 12.480; moisture content 7.617 %; phenol total 62.525 mg GAE/g; antioxidant activity 94.520 %, with the appearance of a yellow-brown color; the distinctive smell; sweet taste with a bitter aftertaste; and overall the panelists’ acceptance level was rather like..

This work has investigated the effect of drying temperature on the crystallite size and lattice strain of NiCoAl-LDH using the Williamson–Hall (W–H) method and tracked the impact of the changes thereof on the electrochemical properties. During the experiments, the drying time was kept unchanged, while the temperature was varied from 70 °C, 80 °C to 90 °C. From the X-ray diffractometer (XRD), Fourier-transform infrared spectroscopy (FTIR), Cyclic voltammetry (CV), and Electrochemical impedance spectroscopy (EIS) results, it was found that the drying temperature had greatly influenced the crystalline structure, the interlamellar domain as well as the electrochemical properties of NiCoAl-LDH. An increment in the crystallite sizes was observed from 4.971 to 12.334 nm as the drying temperature increased from 70 to 80 °C and dropped to 7.681 nm when it reached 90 °C. Similarly, an increase in the specific capacitance was recorded from 1158.26 to 4180.16 Fg−1 at 10 mVs −1 as the drying temperature went up from 70 to 80 °C and dropped to 3775.77 Fg −1 at 10 mVs −1 when the drying temperature increased to 90 °C. Moreover, the sample dried at 80 °C exhibited low internal resistance compared to its counterpart. The best electrochemical performance of the sample dried at 80 °C could be attributed to the larger size of its crystallite. This leads to the conclusion that the electrochemical performance of NiCoAl-LDH could be crystallite size-dependent. Finally, it was proved that the drying temperature (80 °C-12 h) is the best for the drying stage of NiCoAl-LDH.

Abstract The influence of various drying characteristics in the experiment was explored in this study. The drying time and moisture content were used to evaluate the experimental outcomes. The drying of bitter gourd slices using a halogen dryer was done at varied thicknesses (3, 5, and 7 mm) and temperatures (60 °C, 65 °C and 70 °C). The results revealed that the drying time and equilibrium moisture content are considerably affected by the material drying thickness and drying temperature. Furthermore, the Generalized Regression Neural Network (GRNN) model is employed in this study to train and predict the moisture content of bitter gourd as an output parameter. The temperature, bitter gourd thickness, and drying time were considered as input parameters for the GRNN model. Three statistic measures as the R-square, the Root mean square error (RMSE) and the Mean relative percent error (P) were used to validate the accuracy of the trained GRNN model. In training with nine experimental condition datasets, the average score values of R-square, RMSE and P were obtained at 0.995197, 1.498966 and 0.091617, respectively. The test of trained GRNN has been conducted with good agreement between experimental data points and predicted points. The result revealed that GRNN was effective in predicting the moisture content of bitter gourd in a halogen dryer.

BACKGROUND Porosity is a key parameter for exploration and evaluation of shale gas reservoirs. Rapid and accurate determination of shale porosity is crucial for reserve calculation. At present, there are helium gas method, liquid saturation method and image analysis method applied to shale porosity determination, but the comparison between methods and laboratories is lacking. OBJECTIVES To evaluate the applicability of different methods for determining shale porosity. METHODS The characteristics of 69 shale samples from the Longmaxi Formation were studied by analyzing and testing techniques such as X-ray diffraction, argon ion polishing-scanning electron microscopy, and mercury injection-nitrogen adsorption method. Comparison experiments for porosity measurement were conducted among helium method, liquid saturation method and image analysis method. RESULTS The Longmaxi Formation shale had high clay content, many organic pores, small pore throats, and poor seepage capacity, which made it difficult for foreign liquids and gases to quickly enter the pores, which required high resolution of core image data. The liquid saturation method (alcohol method) used 20MPa pressure to saturate the sample for 24 hours, resulting in core damage, and the measured porosity deviated from the true value. The image analysis method ignored the micropores (pore size < 2nm) and mesopores (pore size < 50nm) in the mineral matrix and other factors, making the porosity measurement result unreliable. The porosity measurement result of the helium method was closely related to the drying temperature and stabilization time. The higher the temperature, the larger the measured porosity, and if the stabilization time is too short, the porosity result will be smaller than the real values. CONCLUSIONS After drying the core at 60℃ for more than 24 hours to a constant weight, by setting a reasonable stabilization time, accurate porosity results can be obtained by the helium method. Properly increasing the injection pressure helps to speed up the experimentation rate.

IntroductionThere are several factors that affect the quality and quantity of active ingredients and essential oil (EO) content, including pre and postharvest practices such as drying conditions. One of the most important factors in drying is temperature and then selective drying temperature (DT). In general, DT has a direct effect on the aromatic properties of Anethum graveolens.MethodsOn this basis, the present study was conducted to evaluate the effects of different DTs on the aroma profile of A. graveolens ecotypes.Results and discussionThe results showed that different DTs, ecotypes, and their interaction significantly affect EO content and composition. The highest EO yield was obtained from the Parsabad ecotype (1.86%) followed by the Ardabil ecotype (1.4%), both at 40° C. More than 60 EO compounds were identified, mainly monoterpenes and sesquiterpenes, highlighting α-Phellandrene, Germacrene D, and Dill apiole as major components in all treatments. Besides α-Phellandrene, the major EO compounds at shad drying (ShD) were β-Phellandrene and p-Cymene, while plant parts dried at 40° C showed l-Limonene and Limonene as the main constituents, and Dill apiole was detected in greater amounts in the samples dried at 60 °C. To determine the appropriate DT, simple and factorial based-ANOVA together multivariate analysis demonstrated significant differences in the compounds produced under different DTs. The results indicated that more EO compounds, mainly monoterpenes, were extracted at ShD than other DTs. On the other hand, the content and composition of sesquiterpenes increased significantly when DT was increased to 60 °C. From the genetic backgrounds point of view, the Parsabad ecotype (with 12 similar compounds) and Esfahan ecotype (with 10 similar compounds) were the most suitable ecotypes under all DTs in terms of EO compounds. Accordingly, the present study would help various industries to optimize specific DT(s) to obtain special EO compound(s) from different A. graveolens ecotypes based on commercial requirements.

In this paper, konjac glucomannan (KGM) and zein nanoparticles (NZ) were used as film-forming substrates, and the KGM/NZ blend films (KNZ) were prepared by solution casting. The microstructure, thermal, mechanical, hydrophobic and barrier properties of KNZ were investigated at different drying temperatures (30, 40, 50, 60, 70, 80 ℃). The results showed that when dried at 40, 50, 60 ℃, KGM and NZ had good compatibility and NZ was uniformly dispersed in KGM matrix, the microstructure of KNZ was denser and its mechanical and hydrophobic properties were enhanced significantly (P

Nitrogen nitrates play a significant role in the soil’s nutrient cycle, and near-infrared spectroscopy can efficiently and accurately detect the content of nitrate–nitrogen in the soil. Accordingly, it can provide a scientific basis for soil improvement and agricultural productivity by deeply examining the cycle and transformation pattern of nutrients in the soil. To investigate the impact of drying temperature on NIR soil nitrogen detection, soil samples with different N concentrations were dried at temperatures of 50 °C, 65 °C, 80 °C, and 95 °C, respectively. Additionally, soil samples naturally air-dried at room temperature (25 °C) were used as a control group. Different drying times were modified based on the drying temperature to completely eliminate the impact of moisture. Following data collection with an NIR spectrometer, the best preprocessing method was chosen to handle the raw data. Based on the feature bands chosen by the RFFS, CARS, and SPA methods, two linear models, PLSR and SVM, and a nonlinear ANN model were then established for analysis and comparison. It was found that the drying temperature had a great effect on the detection of soil nitrogen by near-infrared spectroscopy. In the meantime, the SPA-ANN model simultaneously yielded the best and most stable accuracy, with Rc2 = 0.998, Rp2 = 0.989, RMSEC = 0.178 g/kg, and RMSEP = 0.257 g/kg. The results showed that NIR spectroscopy had the least effect and the highest accuracy in detecting nitrogen at 80 °C soil drying temperature. This work provides a theoretical foundation for agricultural production in the future.

Sustainable food production has become increasingly important. Calcium-rich moringa leaves locally grown in warm climates may be a sustainable source of nutrients and many derived products. Drying is essential for preserving and processing moringa. To optimise the drying, it is important to understand the plant's drying characteristics. Based on fluidized bed drying, we investigated established drying models in predicting the experimental results. The experiments were conducted using drying air temperatures from 70 °C to 90 °C and air speeds of 2 m/s, 3 m/s and 4 m/s. The measured drying curved were fitted to the drying models and compared using non-linear regression analysis. It is revealed that the Aghabashlo's model can describe the drying behaviour of moringa leaves with the highest R2 of 0.994. Drying air temperature and speed are significant factors influencing the drying rate. The calcium content in moringa leaves was measured to assess the result of increasing temperatures.

Bromelain is a proteolytic enzyme that can be found in all parts of pineapple plant varieties. Pineapple crown (PC) has higher bromelain activity than other pineapple wastes such as peels and leaves. This study isolated bromelain from one variety of PC, namely Honi, and determined the optimum drying temperature as well as concentration of ammonium sulphate to obtain the best bromelain characteristics such as protein content, unit activity and specific activity. Honi PC was dried at various drying temperatures (35, 40, 45, 50, and 55 °C), and then extracted and purified using ammonium sulphate in various concentrations (20, 40, 60, and 80%), in order, to get bromelain. Furthermore, the yield of isolated bromelain was calculated and the protein content, unit activity and specific activity of bromelain characterised. The highest yield of crude bromelain (CB) was achieved at 35 °C. However, the highest protein level, unit activity and specific activity of CB were achieved at 55 °C (p < 0.05). Purification of CB using concentrations of ammonium sulphate in the range 40 to 80% resulted in a higher protein level (p < 0.05). The highest unit activity and specific activity of bromelain were achieved at a 60% concentration of ammonium sulphate (p < 0.05). 55 °C and 60% were the optimum drying temperature and concentration of ammonium sulphate respectively to achieve the best characteristics (2.16% protein level, 1.61 U/mL unit activity and 0.75 U/mg specific activity) for bromelain isolated from Honi PC. Honi PC isolated bromelain was shown to inhibit the browning reaction on apple fruits. The agroindustry waste product, Honi PC, has potential as a future alternative bromelain source.

Pumpkins are often used as a fodder component and food due to their high nutritional value and share of bioactive components (e.g., carotenoids, polyunsaturated fatty acid (PUFAs)). Due to their high moisture content, they must be preserved; drying is still the most popular method. Our work aimed to assess the optimal drying temperature to keep the best possible nutritional value of the raw material. For this purpose, pumpkin was dried at 40 °C, 60 °C and 80 °C. Then, the proximate composition, carotenoid content, fatty acids, and antioxidant properties were determined. The results indicate that the carotenoids were relatively stable up to 60 °C and then decreased sharply. Furthermore, antioxidant activity was the highest at 40 °C and 60 °C. However, in the case of PUFA content, drying at 80 °C was the most effective, probably due to the shorter exposure time to the stimulus.

This comprehensive study provides an in-depth examination of the convective drying process and drying kinetics of ginger rhizomes (Zingiber officinale), precisely honing in on the influence of moisture content variation on the thermal property of thermal conductivity. Our research reveals a direct correlation between decreasing moisture content and thermal conductivity during drying, conducted under meticulously controlled conditions with a drying temperature range of 10 °C to 60 °C and an optimum drying temperature identified at 60 °C with a relative humidity of 35%. We scrutinise the thermal properties, namely, the thermal conductivity, in relation to moisture content, shedding light on the intricate dynamics involved. The study uncovers the distinct advantage of convective drying over traditional methods, shortening the drying time to just 24 h, compared to the nine and eight days required for open sun and solar tunnel drying, respectively. We identified optimal moisture levels for various ginger types: unblanched (6.63%, thermal conductivity 0.0553 W/m·K), blanched (9.04%, thermal conductivity 0.0516 W/m·K), peeled (8.56%, thermal conductivity 0.0483 W/m·K), and unpeeled ginger (5.98%, thermal conductivity 0.0460 W/m·K). As drying progressed, the moisture content fell from 81% to approximately 6–9%, concomitantly lowering the thermal conductivity from roughly 0.0553 W/m·K to around 0.0460–0.0516 W/m·K. These findings offer significant implications for the food industry, proposing improvements in drying processes and strategies for energy conservation when drying ginger rhizomes and similar agricultural produce. Moreover, this study sets a solid foundation for future investigations into potential applications of these insights to other agricultural products and various drying techniques.

The aim of this study was to evaluate the effect of spray-drying parameters on the physicochemical properties of encapsulated sea buckthorn berry oil. Different carriers (gum arabic, β-cyclodextrin, and their mixture (1:1, w/w)), inlet air temperatures (120, 150, and 180 °C), and carrier-to-oil ratios (2, 3, and 4, w/w) were evaluated. The obtained powders were characterized in terms of the product yield (36.79–64.60%), encapsulation efficiency (73.08–93.18%), moisture content (0.23–3.70%), hygroscopicity (1.5–7.06 g/100 g), solubility (19.55–74.70%), bulk density (0.25–0.44 g/L), total carotenoid content (mg/100 g dm), and antioxidant capacity (871.83–1454.39 μmol TE/100 g dm). All physicochemical properties were significantly affected by the carrier-to-oil ratio and inlet air temperature. Higher carrier-to-oil ratios increased the product yield, encapsulation efficiency, solubility, and bulk density and decreased the powder hygroscopicity. Elevating the drying temperatures during spray drying also increased the product yield, encapsulation efficiency, and solubility, while it decreased the powder moisture content, total carotenoid content, and antioxidant capacity. Based on the physicochemical properties, the use of β-cyclodextrin as a carrier, a drying temperature of 120 °C, and a carrier-to-oil ratio of 4 were selected as optimal conditions for the production of sea buckthorn berry oil powder. The obtained powder is a valuable material for a wide range of applications in the food and nutraceutical industries.

A drying temperature precision control system was studied to provide technical support for developing and further proving the superiority of the variable-temperature drying process. In this study, an improved neural network (INN) proportional–integral–derivative (PID) controller (INN-PID) was designed. The dynamic performance of the PID, neural network PID (NN-PID) and INN-PID controllers was simulated with unit step signals as an input in MATLAB software. A drying temperature precision control system was set up in an air impingement dryer, and the drying temperature control experiment was carried out to verify the performance of the three controllers. Linear variable-temperature (LVT) and constant-temperature drying experiments of cantaloupe slices were carried out based on the system. Moreover, the experimental results were evaluated comprehensively with the brightness (L value), colour difference (ΔE), vitamin C content, chewiness, drying time and energy consumption (EC) as evaluation indexes. The simulation results show that the INN-PID controller outperforms the other two controllers in terms of control accuracy and regulation time. In the drying temperature control experiment at 50 °C–55 °C, the peak time of the INN-PID controller is 237.37 s, the regulation time is 134.91 s and the maximum overshoot is 4.74%. The INN-PID controller can quickly and effectively regulate the temperature of the inner chamber of the air impingement dryer. Compared with constant-temperature drying, LVT is a more effective drying mode as it ensures the quality of the material and reduces the drying time and EC. The drying temperature precision control system based on the INN-PID controller meets the temperature control requirements of the variable-temperature drying process. This system provides practical and effective technical support for the variable-temperature drying process and lays the foundation for further research. The LVT drying experiments of cantaloupe slices also show that variable-temperature drying is a better process than constant-temperature drying and is worthy of further study to be applied in production.

Over the last few decades, many researchers have investigated in detail the characteristics of bioactive compounds such as polyphenols, vitamins, flavonoids, and glycosides, and volatile compounds in fruits, vegetables and medicinal and aromatic plants that possess beneficial properties, as well as consumer acceptance and preference. The main aim of this article is to provide an updated overview of recent research endeavors related to the effects of the drying process on the major bioactive/effective compounds in agricultural products. Particular emphasis was placed on details related to the changes occurring in vitamin C, polyphenols, flavonoids, glycosides and volatile compounds, as well as the antioxidant activity. An analysis of the degradation mechanisms of these compounds showed that vitamin C, phenols, flavonoids and glycosides react with oxygen during the convective drying process under high drying temperatures, and the reaction rate results in degradation in such bioactive compounds due to high reducibility. On the other hand, high temperature results in a short drying time, thus minimizing the degradation of bioactive compounds. The reviewed research works addressing this trend revealed that the ideal drying temperatures for retaining vitamin C, polyphenols, flavonoids, glycosides, volatile compounds and their antioxidant activity were 50–60 °C, 55–60 °C, 60–70 °C, 45–50 °C, 40–50 °C and 50–70 °C, respectively. In conclusion, to maintain plant bioactive components, convective drying at relatively low drying temperatures is strongly recommended.

Kraft lignin, an industrially available by-product from the pulp and paper industry, has revealed enormous potential to be valorised into a wide range of chemicals and biomaterials in the last two decades. However, the understanding of lignin chemistry remains challenging due to its chemical complexity. The goal of this work was to investigate the effect of drying temperature on the chemical, physical, and hygroscopic properties of hardwood kraft lignin isolated from industrial black liquor and elucidate the molecular interactions occurring between water and kraft lignin. Sorption-desorption isotherms determined by dynamic vapour sorption (DVS) technique revealed that the drying process considerably affected the hygroscopicity of the lignin polymer. Moreover, analytical pyrolysis (Py–GC–MS), dynamic NIR spectra collected as a function of relative humidity (0–95%) during sorption-desorption cycles and principal component analysis (PCA), evidenced chemical differences between lignin dried at room (25 °C) temperature and mild oven (55 °C) conditions. The main spectral changes associated with the water sorption in kraft lignin samples were analyzed using difference spectrum technique. 2D NIR spectral correlation analysis provided water sorption mechanism of lignin polymer, disclosing for the first time the sequential order in which water vapour molecules interact with active sorption sites in kraft lignin.

The influence of different drying temperatures and slice thicknesses on the drying kinetics of turmeric slices was studied to show how moisture is removed. The best model for predicting the drying kinetics was also determined. Turmeric slices (3 mm, 5 mm, and 7 mm) were dried at 40, 50, and 60 °C in a laboratory oven dryer. Four thin layer drying models (Newton, Henderson and Pabis, Logarithmic, and Page) were fitted to the experimental data and the selection was done based on the model with the highest correlation coefficient (R2), and lowest reduced chi-square (χ2), the sum of square error (SSE), and root mean square error (RMSE). Drying time varied between 420 min and 1140 min as the air temperature increased from 40 °C to 60 °C. The effective moisture diffusivity coefficient increased with increasing drying temperature and was found to be between 1.35×10-10 m2/s, and 5.00×10-10 m2/s, 3.00×10-10 m2/s and 10.91×10-10 m2/s, and 4.56×10-10 m2/s and 13.00×10-10 m2/s at 40 °C, 50 °C, and 60 °C, respectively. The values obtained for the activation energy for moisture diffusion were found to be 56.809, 56.060, and 45.561 kJ/mol for 3, 5, and 7 mm, respectively. The page model was found to best describe the oven drying of turmeric slices.

Broiler live performance may be influenced by postharvest corn drying temperature, and results could depend on particle size after grinding. The supplementation with an exogenous amylase may improve performance parameters, but responses to enzymes are also affected by particle size. Two parallel experiments were conducted to evaluate the effects of hard-kernel corn dried at 2 temperatures (35°C and 120°C), ground at 2 particle sizes (coarse or fine), and 3 supplementation levels (0, 133, and 266 g ton-1) of an exogenous amylase on live performance, gastrointestinal organ development, energy utilization, and nutrient digestibility. Twelve dietary treatments resulting from a 2 × 2 × 3 factorial arrangement of drying temperature, particle size, and amylase supplementation were evaluated in both experiments. A total of 1,920 day-old male chicks were randomly allocated to 96 floor pens, while 480 chicks were distributed among 4 battery brooder units. Ileal and fecal samples were collected to determine energy utilization and nutrient digestibility using titanium dioxide as inert marker. At 42 D, organs were collected, and relative weight or length was determined. Data were analyzed using a three-way ANOVA in a randomized complete block design. Feeding fine corn-based diets showed improvements on live performance for both studies. At 40 D, supplementing 266 g ton-1 of amylase improved feed conversion ratio (P

This work presents the effect of drying temperature on the formation of poly(vinyl chloride) (PVC) honeycomb microstructures formed by the breath figure technique. Results revealed the self-assembly of honeycomb patterns with small cell diameter and thick cell walls dried at room temperature. An increase in cell diameter and a decrease in wall thickness were observed as drying temperature was increased up to 70 °C while no formation of patterns was noted at temperatures greater than or equal to 80 °C. The presence of honeycomb patterns consequently enhanced the static water contact angle of the PVC layer. Electrowetting experiments revealed more pronounced reduction in the water contact angle on honeycomb-structured PVC compared to a flat PVC layer at any given applied voltage. A proof-of-concept on the feasibility of the honeycomb structures to trap microparticles by electrically-driven droplet actuation was further demonstrated. Corresponding SEM images confirmed the entrapment of microparticles in the honeycomb cells and walls after the electrowetting experiment. These results offer new and facile strategies for tuning the morphological properties of polymeric honeycomb microstructures and its possible application in microparticle trapping and sensing.

In the present work, ginger essential oil (GEO) loaded chitosan (CS) based films incorporated with varying concentrations of gelatin (GE) were fabricated and dried at different conditions (25 °C and 45 °C). The physio-chemical, mechanical and antioxidant potential of the films were determined. Films dried at 45 °C showed better physical attributes and less thickness, swelling degree (SD), moisture content, water vapor permeability (WVP), more transparency, and better mechanical characteristics. Fourier transform infrared spectroscopy (FTIR) revealed the chemical composition and interaction between the functional groups of the film components. X-ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) findings revealed that samples dried at 45 °C had more crystalline structure, were thermally stable, and smoother. Antioxidant results showed that films dried at low temperature showed comparatively more (p < 0.0001) antioxidant activity. Additionally, an increase in gelatin concentration improved the tensile strength and swelling factor (p < 0.05), however, had no significant impact on other parameters. The overall results suggested better characteristics of GEO-loaded CS-GE based edible films when dried at 45 °C.

ABSTRACT: Drying temperature (DT) of corn can influence its nutritional quality, but whether this is influenced by endosperm hardness is not clear. Two parallel experiments were conducted to investigate the effects of 2 yellow dent corn hybrids with average and hard kernel hardness, dried at 3 temperatures (35, 80, and 120°C), and 2 supplementation levels of an exogenous amylase (0, 133 g/ton of feed) on live performance, starch and protein digestibility, and energy utilization of Ross 708 male broilers. Twelve dietary treatments consisting of a 2 × 3 × 2 factorial arrangement were evaluated using 3-way ANOVA in a randomized complete block design. In Experiment 1, a total of 1,920 male-chicks were randomly allocated to 96 floor pens, whereas 480 day-old chicks were distributed among 96 cages for Experiment 2. At 40 d, interaction effects (P < 0.05) were detected on BWG, FCR, and flock uniformity. Supplementation with exogenous amylase resulted in heavier broilers, better FCR and flock uniformity, only in the diets based on corn dried at 35°C. Additionally, interaction effects were observed on FCR due to kernel hardness and DT (P < 0.01), kernel hardness and amylase supplementation (P < 0.001), and DT and amylase supplementation (P < 0.05). Exogenous amylase addition to the diets based on corn with an average hardness improved FCR up to 2 points (1.49 vs. 1.51 g:g) whereas there was no effect of amylase on FCR of broilers fed diets based on corn with hard endosperm. Total tract retention of starch was increased (P < 0.05) in broilers fed diets based on corn with average kernel hardness compared to hard kernel. Corn dried at 80 and 120°C had up to 1.21% points less starch total tract retention than the one dried at 35°C. Supplementing alpha-amylase resulted in beneficial effects for broiler live performance, energy utilization, and starch total tract digestibility results. Treatment effects on starch characteristics were explored. Corn endosperm hardness, DT and exogenous amylase can influence the live performance of broilers. However, these factors are not independent and so must be manipulated strategically to improve broiler performance.

This study focused on the experimental drying of Bo Chinh ginseng by the ultrasound-assisted heat pump drying method, in which the effects of drying air temperature (T), ultrasonic power (P), intermittency ratio of ultrasound generator (A) on the moisture effective diffusion coefficient (Deff), saponin content (Sp) and color change (dE) during the drying process were determined. The results showed that the drying time was reduced from 12.5 h at 35 °C to 8.9 h at 40 °C and greatly reduced to 5.8 h at 55 °C. The moisture diffusion coefficient Deff and color change index increased with the increase in drying temperature. Meanwhile, from 35 °C to 45 °C, the saponin content after drying tended to increase gradually, but when the temperature continued to rise from 45 °C to 55 °C, the saponin content decreased. The effect of ultrasonic power in the drying process was in particular as follows. The drying time of 8.8 h at 40 W ultrasonic power reduced to 7.8 h at 80 W ultrasonic power, and reduced to 7 h at 160 W ultrasonic power. The remaining saponin content after drying tended to increase gradually at the power level of 40–120 W (from 89.2% to 95.2%) and decrease when the power increased from 120 to 160 W (from 95.2% to 90.5%). The moisture diffusion coefficient Deff also increased with the increase in ultrasonic power. Meanwhile, the color change of dried products decreased as the ultrasonic power increased in the range of 40–120 W but increased with the ultrasonic power range from 120 to 160 W. Additionally, the experimental method and Box–Behnken design were used for optimizing the drying process with the optimal drying conditions such as drying air temperature of 45.2 °C, ultrasonic power of 127.7 W and intermittency ratio of ultrasound generator of 0.18.

The drying temperature is one of the crucial parameters that impacts the physical, chemical, and biological properties of edible films (EFs). This parameter determines the degree of crystallinity, which can further impact the film’s mechanical, barrier, and optical properties. The present work is designed to investigate the effect of different drying temperature conditions (25 °C and 45 °C) on ginger essential oil (GEO) loaded Gelatin-sodium alginate composite films over their physical, chemical, and antioxidant properties. Results indicated that drying of films at 25 °C had a positive effect on certain properties of the EFs, such as the moisture content (MC), water solubility (S), swelling degree (SD), water vapor permeability (WVP), and mechanical and optical properties. SEM analysis showed that films dried at 25 °C presented more uniform surface properties with fewer cracks and pores compared to films dried at 45 °C. TGA analysis demonstrated the higher thermal stability of the films when dried at 25 °C. Findings obtained from X-ray diffraction (XRD) and fourier-transform infrared spectroscopy (FTIR) showed film crystallinity and electrostatic interactions between GE, SA, and GEO. Results obtained from antioxidant assays revealed that films dried at 25 °C showed comparable antioxidant capacity to that of butylated hydroxytoluene (BHT). Furthermore, it was found that the addition of SA and GEO to the blank GE films improved their physical, chemical, and antioxidant properties. The present work suggests that GEO loaded GE-SA based films showed better physical, chemical, and antioxidant potential when dried at a lower temperature. These novel materials can be utilized as potential packaging materials in the food industry.

The effect of drying temperature on total anthocyanin and moisture contents in purple waxy corn kernel was investigated by using a tunnel dryer. The amount of anthocyanin and moisture content were studied with the relatively low drying temperature of 60–80 °C under controlling air velocity at 1.5 m/s. The experimental results reveal that moisture content in purple waxy corn kernel slightly decreases with time and the lowest moisture content obtained by using the present method is 13%wb (wet basis). The drying rate increases with increasing temperature and the highest rate is obtained at the temperature of 80 °C (0.1492% min−1). Total anthocyanin content in purple waxy corn kernel was strongly affected by the drying temperature and moisture content. The highest total anthocyanin content was obtained at the temperature of 65 °C with the moisture content of 13%wb, which is the best condition for preserving purple waxy corn kernel by using a tunnel dryer.

This study examines the model development of the drying process of corn grains as a dynamic system. The appropriate use of a dynamic model for the drying process of corn grains could lead to an effective method for optimizing the system. The optimal control strategy can be determined by predicting the future behaviors of the process using a dynamic model. In this work, the dynamic characteristic of the water loss of corn grains during dynamics treatment of temperature in the drying process was measured in a continuous manner using a precise load cell. The nonlinear autoregressive with external input (NARX) neural network is used to identify and develop a model of dynamic characteristics of the drying process of corn grains. Then for model training and validation, the dynamic responses of the rate of water loss of corn grains to drying temperature were used. A three-layered NARX neural network model consists of 1-10-1 number neurons of each layer with two times delay was successfully developed to identify and make a model such a complex system. The developed model showed the accuracy of the rate water loss of corn grains during the drying process with the mean square error (MSE), and coefficient of determination (R-squared) values are 1.88892 x 10-4 and 0.891594 consecutively.

The article presents an experimental study of mechanical properties of cellulose biofilm produced by bacterial fermentation process. Naturally derived biomaterial has great current and potential applications therefore the conditions of material preparation as well as control and prediction of mechanical properties is still a relevant issue. Bacterial cellulose was obtained as a secondary product from Kombucha drink. Presented technique for material preparation and drying is particularly simple and easy to access. The influence of drying temperature (25 °C, 50 °C and 75 °C) on the sample size (thickness and planar dimensions) and mechanical properties (tensile and bursting strength) of cellulose biofilm has been evaluated. It was estimated that during drying biofilm specimens lost up to 92 % of weight and up to 87 % of thickness therefore planar specimen dimensions varied insignificantly. The study showed that the drying temperature is important for optimum strength properties of bacterial cellulose biofilm. The maximum tensile strength (27.91 MPa) was recorded for the samples dried at temperature of 25 °C, when the moisture from the biomaterial is removed gradually and good deformation properties are ensured (respectively tensile extension 18.8 %). Under higher drying temperature biomaterial shows lower values of tensile strength and higher values of bursting strength. The maximum bursting strength (57.2 MPa) was recorded for samples dried at 75 °C when punch displacement changes were insignificant for all tested samples (from 17.8 mm to 21.7 mm). DOI: http://dx.doi.org/10.5755/j01.ms.25.3.20764

Drying process was one of the main factors in preserving noodles because it can reduce water content to less than 12 % (w/w (weight by weight)). The objectives of this study were to optimize the drying process of corn noodles using fluidized bed dryer (temperatures of 50 °C, 60 °C, and 70 °C with airflow velocities of 0.73 m‧s-1, 1.53 m‧s-1, and 2.17 m‧s-1) and to determine the influence of water addition (60 %, 70 %, and 80 % (w/w)) to the dough of corn noodles. The results showed that the best rehydration profile of dried noodles was obtained from drying process at temperature of 60 °C with airflow velocity of 2.17 m‧s-1. The quality of dried corn noodles was influenced by final moisture content of dried noodles and water addition. The critical moisture contents on water additions of 60 %, 70 %, and 80 % were 12, 11, and 10 % (w/w), respectively. The results also showed the optimum quality of dried corn noodles which was obtained from the dough with water addition of 80 %, drying temperature of 60 °C with velocity of 2.17 m‧s-1 for 107 minutes, and moisture content of 10 %. This has similar properties of moisture content, cooking loss, elongation, and hardness to the conventional drying.

Red currants (Ribes rubrum L.) were dried by vacuum drying on different drying temperatures (30, 40, 50, 60 and 70 °C) at constant pressure (20 mbar). The main goal of the research was to investigate changes of physical and chemical properties of red currants at different conditions of vacuum drying process. Moisture content, water activity, rehydration power, total color change, shear force and total monomeric anthocyanin compounds were used as the most suitable quality indicators of dried red currant. The lowest moisture content, total color change and the highest rehydration power were noticed in the red currant sample dried on 60 °C, 20 mbar, 16 h, while the lowest water activity, shear force and the highest content of total monomeric anthocyanins were observed in the sample dried on 40 °C, 20 mbar, 40 h. Five empirical models (Henderson-Pabis, modified Henderson-Pabis, simplified Fick's diffusion, Peleg's and two term) were used for description of vacuum drying process.

Sunflower seed storage is accompanied by the loss of seed vigor. Seed drying is a key link between seed harvest and seed storage; however, to date, the effect of seed drying on sunflower seed deterioration during storage remains unclear. The present study performed hot air drying for sunflower seeds with an initial moisture content of 30% to examine the manner in which drying temperature (35, 40, 45, 50, and 55°C) affects the drying performance and seed vigor following storage process (6 and 12 months). A drying temperature of 40°C was evidently safe for sunflower seeds, whereas the high drying temperatures (HTD, 45, 50, and 55°C) significantly lowered sunflower seed vigor by regulating the fatty acid metabolism, glycometabolism, and abscisic acid (ABA)/gibberellin (GA) balance. HDT significantly increased the seed damage rate and accelerated sunflower seed deterioration during natural and artificial aging process. Further biochemical analysis indicated that HDT significantly increased lipoxygenase and dioxygenase activities, leading to malonaldehyde and reactive oxygen species over-accumulation during storage. During early seed germination, HDT significantly inhibited fatty acid hydrolysis and glycometabolism by decreasing triacylglycerol lipase, CoA-SH oxidase, and invertase activities. Moreover, HDT remarkably increased ABA levels but reduced GA levels by regulating gene expressions and metabolic enzyme activities during early imbibitions. Cumulatively, the seed drying effect on sunflower seed vigor deterioration during the storage process may be strongly related to fatty acid oxidation and hydrolysis metabolism, toxic substance accumulation, and ABA/GA balance.

Fermented fish dip is a popular condiment in Thailand and the Lao People’s Democratic Republic. Thai fermented fish dip (TFFD), can be dried to increase its shelf life and ease of transportation. Dried TFFD can be rehydrated to return the powder to its original, paste-like form. Pre-cooked TFFD paste was dried at three different temperatures (40, 60, and 80 ºC). Total plate count, yeast and mold count, CIE colour values (L*, a*, and b*),non-enzymatic browning, and sensory scores of the resulting powders were determined. The CIE colour values and sensory scores were alsoanalysed for rehydrated TFFD. Increasing the drying temperature did not affect the total plate count or yeast and mold count. When dried at 80 ºC, the L* value of TFFD powder was reduced, although the a* and b* values were unaffected compared with lower temperatures. All CIE colour values of rehydrated TFFD decreased as drying temperature increased. Drying temperature did not affect the sensory scores of dried TFFD powder. However, rehydrated samples that had been dried at 80 ºC had significantly lower sensory colour scores than those dried at 40 or 60 ºC. Overall preference rankings of dried and rehydrated TFFD dried at 40 and 60 °C were better than for those dried at 80 °C. Due to an undesirable colour change in the rehydrated product, 80 ºC was deemed to be an unsuitable temperature for drying TFFD paste. In conclusion, both 40 and 60 ºC are appropriate temperatures for drying the product.

Various conditions of a parboiling process affect the qualitative parameters of paddy milling. In this study, the effects of drying temperature (45 and 60 °C), moisture content (8, 10 and 12% w.b.), steaming time (10, 20 and 30 min) and paddy varieties (Hashemi and Alikazemi) were investigated on head rice yield (HRY). The samples were husked using a rubber roller husker and whitened by a laboratory abrasive whitener. Results showed that the main effects of all parameters were significant on HRY (P

The hopcalite (CuMnOx) catalyst is a well-known catalyst for oxidation of CO at ambient temperature. It has prepared by co-precipitation method and the preparation parameters were like Copper/Manganese (Cu:Mn) molar ratios, drying temperature, drying time, calcination temperature and calcination time has an influence on activity of the resultant catalyst. The activity of the catalyst was measured in flowing air calcinations (FAC) conditions. The reaction temperature was increased from ambient to a higher value at which complete oxidation of CO was achieved. The particle size, weight of catalyst and CO flow rate in the air were also influenced by the activity of the catalyst for CO oxidation. The characterizations of the catalysts were done by several techniques like XRD, FTIR, BET, SEM-EDX and XPS. These results were interpreted in terms of the structure of the active catalyst. The main aim of this paper was to identify the optimum preparation conditions of CuMnOx catalyst with respect to the performance of catalyst for CO oxidation.

The thermal treatment of wood changes its structure due to the degradation of wood polymers (cellulose, hemicellulose and lignin), so the physical properties of wood are either improved or degraded. Color changes apply not only to natural wood, but also to such wood composites for which some amount of glue is used in their construction (e.g., plywood, blockboard or laminboard). This article is focused on the analysis of hornbeam and field maple wood color changes influenced by drying temperature. Two types of drying modes were used: hot-air mode where the temperature of the drying environment was 60 °C, and high-temperature mode with a drying temperature of 120 °C. The drying mode was divided into two phases depending on the moisture content of the wood. The compared woods had similar values of color coordinates at the beginning of drying. During hot-air drying, the largest changes in color coordinates occurred during the first 24 h. The total color difference between the color at the end and the beginning of drying was 7.3 for hornbeam and 11.1 for maple. The overall color difference between the compared woods was minimal. During high-temperature drying (120 °C), the color changes of the dried woods were more pronounced. In the case of maple wood, there was a very significant change in color and the value of ΔE* was twice as high as for hornbeam. The total color difference between the color at the end and at the beginning of drying was 8.7 for hornbeam and 18.9 for maple.

As a mechanical, thermal, diffusion and chemical operation, extrusion causes changes in the properties of raw materials mainly due to the characteristics of the extruder and extrusion conditions (temperature, pressure and shear stress). As extruded products based on cereals occupy an important place in modern nutrition, they are suitable carriers of functional components. In every technological process, it is very important to correctly define the parameters of production in order to achieve a good and uniform quality of products with as little as possible losses of the nutritional and functional properties of raw materials. On the basis of the experimental results on the physical, chemical and antioxidant properties of corn flakes, as well as the use of Standard Score analysis, it can be concluded that the optimal drying temperature for corn flakes is 84 °C.

A small, novel wheat drying oven was designed, and tested in order to validate the possibility of recovering diesel engine waste heat as thermal energy. Prior to experiments, the theoretical probability was conducted, and it was confirmed that the thermal energy required for drying wheat could be satisfied by reusing the diesel engine waste heat. Three different experiment parameters, including air temperature, baffle angle, and drying time, were controlled to optimize the results. Based on the experiment data, the optimum temperature for drying wheat was 55°C, and the optimum baffle angle was 23.25°. The drying efficiency decreased as the drying temperature and drying time increased. The moisture content of wheat decreased from 26.0% to 20.0% with 55°C hot air when the proposed wheat drying oven was used. The test results demonstrated that the proposed oven could be made to work.

Edible flowers have been used in the food and beverage industries because of their high nutritional value, flavor, and scent. For the storage of edible flowers used in these industries, drying is a necessity to store the materials more easily and prevent the damage of metabolites in the flowers. However, drying may affect metabolite retention because drying conditions can differ according to the various methods. In this study, Agastache rugosa flowers were dried using four different methods (oven drying at 25 ± 1 °C, 50 ± 1 °C, 80 ± 1 °C, and freeze drying) and primary and secondary metabolites were analyzed using high-performance liquid chromatography (HPLC) and gas chromatography time-of-flight mass spectrometry (GC-TOF/MS). Freeze-dried flower samples contained higher levels of carotenoids (lutein, 13Z-β-carotene, β-carotene, and 9Z-β-carotene) and phenolics (rosmarinic acid, ferulic acid, and sinapic acid). Contrarily, the 80 °C oven-dried flower samples contained higher levels of most amino acids and flavonoids (including acacetin and tilianin) and at 25 °C and 50 °C contained higher levels of carbohydrates. Therefore, freeze-drying is a suitable method for retaining carotenoids and phenolics. In contrast, oven drying at 50 °C was highly recommended to retain amino acids and flavonoids.