Hot Air Research Articles

Spray Drying of Inca Peanut Meal Protein Hydrolysate to Produce Protein Powder Drink Mix

The optimal conditions (maltodextrin concentration and inlet air temperature) for spray drying Inca peanut meal protein hydrolysate (IMPH) were determined. The maltodextrin concentration was varied at 5, 10 and 15 % by weight, and inlet air temperature was varied at 150, 160 and 170 °C. The IMPH was subjected to spray drying, where the feed solution was atomized into fine droplets and exposed to a hot air stream, leading to rapid drying and the formation of powder. The moisture, protein, yield, water activity and water solubility index (WSI) of IMPH powder were analyzed. The optimal condition for spray drying IMPH powder utilized 10 % maltodextrin and an inlet air temperature of 160 °C. Under these conditions, the moisture, protein, yield and WSI of IMPH powder were 2.93, 36.93, 38.95 and 99.59 %, respectively, while water activity was 0.41. IMPH powder particles were spherical and non-agglomerate. Inca peanut meal protein powder drink mix (IMPD) with cocoa flavor was the most acceptable. The IMPD with cocoa flavor could be promoted as a high protein and high dietary fiber product. It could be kept at 35 ± 2 °C for 12 weeks, whilst retaining good microbiological properties. HIGHLIGHTS The optimal conditions for spray drying Inca peanut meal protein hydrolysate (IMPH) were determined to be 10% maltodextrin and an inlet air temperature of 160 °C. This resulted in high yield, protein content, and water solubility, while keeping moisture and water activity low. IMPH powder had spherical, non-agglomerated particles, and cocoa-flavored Inca peanut protein powder drink mix (IMPD) was the most preferred in sensory evaluations. The IMPD with cocoa flavor was identified as a high-protein, high-dietary-fiber product, suitable for storage at 35 °C for up to 12 weeks while maintaining good microbiological quality. The study highlights the nutritional benefits of the cocoa-flavored IMPD, which includes essential amino acids, omega-3 fatty acids, and antioxidant properties. GRAPHICAL ABSTRACT

Porous Monolithic Perovskite Structures for High-Temperature Thermochemical Heat Storage in Concentrated Solar Power (CSP) Plants and Renewable Electrification of Industrial Processes

A novel approach towards thermal energy storage of surplus renewable energy (RE) is introduced via a hybrid thermochemical/sensible heat storage concept implemented with the aid of porous structures made of redox metal oxides, capable of reversible reduction/oxidation upon heating/cooling in direct contact with air, accompanied, respectively, by endothermic/ exothermic heat effects and demonstrating fully reversible dimensional changes under cyclic operation. The proposed modular storage units can be heated during the day to a level exceeding the metal oxide’s reduction onset temperature either by hot air streams from air-operated Concentrated Solar Power (CSP) tower plants or via surplus/cheap RE-electricity from photovoltaics, wind, or other renewable sources (“charging”/energy storage step). When this RE sources become non-available or upon demand, the fully charged system can transfer its energy to a controlled airflow that passes through the porous oxide block and initiates the exothermic oxidation of the reduced metal oxide. Thus, a hot air stream is produced which can be used to provide electricity or exploitable heat for industrial processes. The present work elaborates on the operating principles and the potential application of this concept and reports progress in the preparation and shaping of reticulated porous ceramics (RPCs also known as “ceramic foams”) from CaMnO3-based perovskite compositions and their preliminary testing with respect to cyclic reduction-oxidation.

Airflow Characteristics in Conveyor Type Damper for Hot Air Temperature Changes

The aim of this study was to present the characteristics of a hot airflow in a conveyor type dampers under the hot air temperature changes. The amount of space occupied by the damper was reduced by 50 %, and by efficiently managing the damper's airflow rate even in the face of extreme external conditions and constant air volume proportional control, a conveyor-type damper with a significant energy-saving effect has been explored. It was configured to control the degree to which it was opened by operating the folding conveyor drive mechanism, enabling the damper to modify airflow. In this study, the mass flow rate of heated air through the conveyor-type damper increased in proportion to the damper port's expansion. The mass flow rate of air decreased as the temperature of air intensified. In addition, the thermal energy of the air flowing in the conveyor-type damper improved in ratio to the increase in the damper opening. The findings indicate a 50 % reduction in the damper's occupied space, indicating a significant energy-saving impact of the conveyor-type damper. This is because the damper's air volume is effectively controlled even in the face of severe external conditions, as it is proportionately controlled throughout. The understanding of the properties of airflow for the hot temperature change is strengthened by this research. Furthermore, this study may provide useful direction for future research and industry optimization.

Assessing the Physicochemical Characteristics: A Comparative Analysis of Various Drying Methods in Osmotic Treated Fruit Slices

Background: Due to their high perishability, we cannot store fruits in their fresh form for long. The different drying techniques have affected the physical and nutritional qualities of the dried fruit pieces. Adoption of osmotic dehydration will help to protect and improve the quality characteristics of the final products. Methods: Selected fruit slices, viz., apple, pineapple, guava, mango and banana, were subjected to sugar osmosis (60°Bx for up to 48 hours), followed by drying in different drying methods, viz., open sun (ODT), solar tunnel (SDT) and hot air drying (CDT) and the physical and chemical characteristics of the end products were analysed. Result: The osmosis process improved the total soluble solids content, while CDT and SDT improved both the rehydration of the dried fruit slices and the percentage of weight loss. The desirable physical attributes of the dried products significantly varied among the different drying methods and within the fruit slices. The CDT-dried samples had better nutritional properties in terms of total phenol content and antioxidant activity than did the other drying methods and fresh samples, except for vitamin C content, which was greater in fresh fruit slices. The results recommended using CDT techniques in osmosis-treated fruit slices, which could improve fruit's physical and nutritional properties and be useful as good functional foods for a long time.

Analysis and structure optimization of the flow and temperature fields of the large-scale hot air drying room

Large-scale hot air drying rooms play a crucial role as efficient drying equipment across various industries. The uniform distribution of hot air is a crucial factor influencing the drying quality of large-scale hot air drying rooms. This study focuses on camellia seeds as the drying subject. Building on a porous media model and the drying kinetics of camellia seeds, a CFD model of the drying room was established. Three-dimensional simulations of the internal flow and temperature fields were performed using CFD software, and the simulated results aligned well with experimental data. To improve the uniformity, this study introduced an optimized design featuring a combination of a Type E3 air guide hood with five guiding plates and a fan, selected based on optimized angles (θ1 = 5°, θ2 = 10°). Under the condition of improving the structure without introducing a new heat source, the optimization ensured a significant improvement in flow field uniformity while making the temperature field closer to the desired ideal temperature. This offers a reference for the design and research of hot air drying equipment and hot air drying rooms.

Impact of Dehydration Techniques on the Nutritional and Microbial Profiles of Dried Mushrooms.

The global consumption of dried mushrooms has increased worldwide because of their rich nutritional value and culinary versatility. Dehydration methods such as sun drying, hot air drying, freeze drying, and microwave drying are employed to prolong the shelf life of a food product. These methods can also affect the food product's nutritional value and the final product's microbial profile. Each technique affects the retention of essential nutrients like vitamins, minerals, and bioactive compounds differently. Additionally, these techniques vary in their effectiveness at reducing microbial load, impacting the dried mushrooms' safety and shelf life. This review addresses the gap in understanding how different dehydration methods influence dried mushrooms' nutritional quality and microbial safety, which is crucial for optimizing their processing and consumption. It targets researchers, food processors, and consumers seeking to improve the quality and safety of dried mushrooms. This review comprehensively examines the impact of major dehydration techniques, including sun drying, hot air drying, microwave drying, and freeze drying, on the nutritional and microbial profiles of dried mushrooms. Each method is evaluated for its effectiveness in preserving essential nutrients and reducing microbial load. Current research indicates that freeze drying is particularly effective in preserving nutritional quality, while hot air and microwave drying significantly reduce microbial load. However, more well-designed studies are needed to fully understand the implications of these methods for safety and nutritional benefits. These findings are valuable for optimizing dehydration methods for high-quality dried mushrooms that are suited for culinary and medicinal use.

Influence of drying method on the shelf life of artisanal pasta

Efforts to optimize pasta drying often face challenges due to the complexity of operational variables. This study aimed to optimize conventional fixed-bed convective drying of artisanal pasta using a desirability function approach and assess the influence of drying methods on shelf life. Three methods were compared: optimized conventional fixed-bed convective drying (O-CFBCD), hot air microwave drying (HAMD), and convective tray drying (CTD). This study underscores the importance of exploring and regulating pasta quality parameters to meet both industry standards and consumer preferences for marketable products with sensory appeal. While all three drying methods show promise for producing quality pasta, there is a need for improved initial moisture control, particularly in the CTD condition, to ensure compliance with regulatory standards and mitigate microbiological risks associated with high water content. Over time, most sensory parameters exhibited enhancement, aligning with consumer expectations for high-quality products. This suggests that continuous monitoring and optimization of drying processes are essential for maintaining and improving pasta quality throughout its shelf life.

Increase the economic potential of the Ambulu Community by providing appropriate batik drying technology

One of the MSMEs developed Batik as a regional product is Rezti's Batik. Rezti's Batik is located in Ambulu, Jember Regency, about 28.4 km from the University of Jember. Increasing the number of consumer orders has made Rezti's Batik production continue to increase. One of the obstacles faced by Rezti's Batik is the process of making Batik which takes a long time because the drying process still relies on heat from the sun, which takes 4-6 hours. The process can also take longer if the rainy season slows the production process's completion. The solution method is the manufacture of appropriate technology in the form of installing a batik cloth dryer. The batik cloth drying installation implementation at Rezti's Batik is a drying system that utilizes heat from the furnace in the sagging process as a heating medium. The designed dryer consists of a stove as a heat generator which will later be distributed with air from the blower so that the hot air will spread evenly throughout the room.

Effect of Water Content in Semidry Grinding on the Quality of Glutinous Rice Flour.

The grinding process is one of the key factors affecting the quality of glutinous rice flour (GRF). As an emerging grinding method, semidry grinding aims to solve the problems of the high yield of wastewater in traditional wet grinding and the high content of damaged starch in dry grinding, in which the water content has a great influence on the quality of GRF. However, semidry grinding has not yet been formally put into production due to limitations such as the long time required to adjust the water content of rice grains. Therefore, this work was carried out to shorten the soaking time of glutinous rice (GR) by hot air pretreatment, and to conduct a systematic and in-depth study of the effect of water content on the quality of GRF, including water distribution, water hydration properties, thermal properties, rheological properties, and microstructure. The results showed that the GRF with higher water content had lower water solubility and higher enthalpy of pasting, which were due to the low content of damaged starch and the high degree of crystallization. The particle size of the GRF became smaller as the interaction between water and starch was enhanced and the GR was softened. In addition, the viscosity and elasticity of the GRF were also improved with an increase in water content. This work provides theoretical guidance for the improvement of semidry grinding to a certain extent.

Rheological analysis of network structure of raw natural rubber prepared by different processing techniques

The performance of raw natural rubber (NR) is dominated by its network structure, particular the levels of long chain branching (LCB) and entanglement. Here, three type of raw rubbers were prepared using different processing methods for commercial grade NRs. Linear and nonlinear viscoelastic behaviors, as well as stress relaxation, were analyzed to access their network structures. The third relative harmonic, phase angle, and first to second quarter-period integral ratio of stress curve were utilized as indicators for the nonlinearity of samples. By combining these values with flow activation energy and characteristic times, it can be confirmed that naturally coagulated NR showed higher elasticity than acid-coagulated NR due to high levels of LCB and entanglement, and hot air drying could lead to chain degradation. These findings correlated with molecular weight parameters, gel content and Mooney viscosity results. This research establishes a method for monitoring raw NR quality and predicting its properties.

Evaluation of the effect of ultrasound-assisted hot air drying on the drying characteristics and physicochemical properties of cherries based on the entropy-weighted TOPSIS method.

To address the challenges associated with prolonged traditional hot air drying (HAD) times and significant nutrient loss in cherries, this study employs ultrasound-assisted hot air drying (USA-HAD) technology. The study investigates the impacts of various ultrasound (US) frequencies, US powers, and hot air temperatures on the drying kinetics, physicochemical properties, texture attributes, and microstructure of cherries during drying. Cherry physicochemical quality serves as the evaluation criterion, with the entropy-weighted TOPSIS method used to identify the optimal drying parameters. The findings indicate that USA-HAD accelerates the drying process, reduces drying time, and enhances drying efficiency. In comparison to natural drying, USA-HAD significantly preserves polysaccharides, total phenolic content, total flavonoid content, and organic acids in cherries, while boosting antioxidant activity. Concurrently, it reduces color intensity, as well as the hardness, chewiness, and gumminess of dried cherry products. Microstructural observations under different drying methods reveal an increase in surface micropores and relatively intact tissue structure. Under conditions of 55°C, 48W, and 28kHz, cherries exhibit superior overall quality based on the TOPSIS relative closeness degree. This study offers practical insights for optimizing post-harvest processing of cherries. PRACTICAL APPLICATION: In this rapidly evolving era, the application of combination drying technology is clearly on the rise. The USA-HAD treated cherries had better nutritional and bioactive than HAD. The conclusions obtained indicate that the USA-HAD technology has more potential for development.

Artificial intelligence as a tool for predicting the quality attributes of garlic (Allium sativum L.) slices during continuous infrared-assisted hot air drying.

Effective drying methods are a highly suitable solution for ensuring stable food supply chains, reducing postharvest agricultural losses, and preventing the spoilage of perishable fruits and vegetables. Moreover, machine learning techniques are innovative and dependable, especially in addressing food spoilage and optimizing drying processes. This study utilized a continuous infrared (IR) hot air dryer to dry garlic (Allium sativum L.) slices. The experiments were conducted at different levels of IR power, air velocities (V), and temperature (T). The relationships between the input process parameters (IR, T, and V) and response parameters, including effective moisture diffusivity (Deff), drying time, and physicochemical properties of the dried slices (rehydration ratio [RR], total color change, flavor strength, and allicin content in the garlic), were modeled using an artificial neural network (ANN). Our findings showed that the maximum Deff of 6.8×10-10m2/s and minimum drying time of 225min were achieved with an IR of 3000W/m2, an air velocity of 0.7m/s, and a temperature of 60°C. The total color change and RR values increased with IR and higher air temperature but declined with higher air velocity. Furthermore, the garlic's flavor strength and allicin content levels decreased as the IR and air temperature increased. The results demonstrated a significant influence of the independent parameters on the response parameters (p<0.01). Interestingly, the ANN predictions closely matched the test data sets, providing valuable insights for understanding and controlling the factors affecting drying behaviors.

Changes in the Volatile Flavor Substances, the Non-Volatile Components, and the Antioxidant Activity of Poria cocos during Different Drying Processes.

Poria cocos (Schw.) wolf (P. cocos) is an important medicinal material with both therapeutic and edible properties. This study investigated volatile constituents, amino acids, proteins, polysaccharides, triterpenoid ingredients, and alcohol-soluble extracts on P. cocos during eight drying processes. A total of 47 volatile components were found and identified; the main volatile components of shade drying (SD) and hot-air drying at 50 °C (HD50) were esters and alcohols, while for drying in hot air at 60 °C~100 °C (△ = 10 °C) and infrared drying (ID), the main compounds were aldehydes and hydrocarbons. The amino acids in P. cocos remained the same when dried with various methods. Compared with SD samples, with the temperature increase, the content of amino acids showed a trend of first decreasing and then increasing, while the content trend of proteins was the opposite. The HD70 samples had the highest content of polysaccharide, triterpenoid ingredients, alcohol-soluble extracts, and antioxidant activity. Furthermore, volatile compounds showed a correlation between non-volatile constituents. This research provides evidence that the aroma, active components, and activity of P. cocos were affected by the drying method.

Mechanical, Fracture, and Thermal Characterization of Post-Cured Hybrid Epoxy Nanocomposites Reinforced with Graphene Nanoplatelets and h-Boron Nitride

The post-curing process of cured composites is essential in enhancing the strength, stiffness, elevating the glass transition temperature, and reducing residual stress in polymer thermoset composites. The curing temperature and time are the key factors that affect these properties. In-situ polymerization method was used to prepare composites with varying weight percentages of graphene nanoplatelets (GNP) and hexagonal boron nitride (h-BN) nanofillers (0.1, 0.2, and 0.3 wt% GNP-based composites; 0.3, 0.4, and 0.5 wt% h-BN-based composites; 0.4, 0.5, and 0.6 wt% h-BN+GNP-based composites). The cured composites were post-cured at temperatures of 80°C, 120°C, and 160°C for 120 minutes in a hot air oven. The presence of GNPs and h-BNs in the composites is confirmed using Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). Further mechanical and thermal properties were evaluated by conducting tensile, flexural, impact, fracture and differential scanning thermometry (DSC) tests. The simulation analyses were performed using Ansys software, and the results demonstrated a strong correlation with the experimental data, with discrepancies between the two consistently within a standard margin of 20%.

POTENTIAL USES OF DRIED APRICOT PULP IN OBTAINING FUNCTIONAL PRODUCTS

In this study, apricot pulp samples dried by hot air, microwave and microwave-hot air combination methods were ground into powder. By analyzing certain parameters of the obtained apricot pulp powder samples (total phenolic content, antioxidant capacity and color values), the apricot pulp powder obtained by the drying method (300 W-60ºC) determined by prioritizing the functional properties in yogurt and bread production, was used in 5 different ratios (10%, 20%, 30%, 40% and 50%).

Suppression of Hotair Gene in Small-Cell Lung Cancer Effect The Differentially Expressed Genes and Inhibit Progression of the Disease

Suppression of Hotair Gene in Small-Cell Lung Cancer Effect The Differentially Expressed Genes and Inhibit Progression of the Disease

Hypermethylation in Ovarian Cancer of Long Non-Coding RNA Genes: &lt;i&gt;HOTAIR&lt;/i&gt;, &lt;i&gt;GAS5&lt;/i&gt;, &lt;i&gt;LINC00472&lt;/i&gt;, &lt;i&gt;LINC00886&lt;/i&gt;, &lt;i&gt;TUG1&lt;/i&gt;

Recently, more and more data have been accumulating indicating the role of long non-coding RNAs (lncRNAs) in the regulation of biological processes in cells, as well as in the mechanisms of cancer development and progression. Aberrant methylation of promoter regions of both protein genes and lncRNA genes can disrupt their expression and functional activity. Using bioinformatics databases, six lncRNA genes (GAS5, HOTAIR, LINC00472, LINC00886, SNHG17 and TUG1) with CpG islands, differentially expressed and presumably hypermethylated in tumors of patients with ovarian cancer (OC) were selected. A statistically significant (p 0.05) increase in the methylation level in tumours was demonstrated in a sample of 93 OC specimens using methylation-specific real-time PCR assay. Moreover, for the genes LINC00472, LINC00886, SNHG17 and TUG1, hypermethylation in OC was detected for the first time. 5 genes (except SNHG17) showed a further increase in methylation levels at a more advanced stage, and 4 genes (except SNHG17 and LINC00886) showed a significant association with metastasis. Using real-time RT-PCR, differential changes in the expression level of the GAS5, HOTAIR, SNHG17 and TUG1 genes and a significant correlation of methylation with expression for the GAS5 gene were shown. Thus, hypermethylation associated with the progression and/or development of OC was detected for six lncRNA genes, which is important for elucidating the epigenetic processes involved in the pathogenesis of OC and can be used as new biomarkers of OC.

Effects of Moisture Migration and Changes in Gluten Network Structure during Hot Air Drying on Quality Characteristics of Instant Dough Sheets.

The impact of hot air drying temperature on instant dough sheets' qualities was investigated based on water migration and gluten network structure changes. The results revealed that the drying process redistributed the hydrogen proton, with deeply bound water accounting for more than 90%. The T2 value decreased as the drying temperature increased, effectively restricting moisture mobility. Meanwhile, microstructural analysis indicated that instant dough sheets presented porous structures, which significantly reduced the rehydration time of instant dough sheets (p < 0.05). In addition, elevated drying temperatures contributed to the cross-linking of proteins, as evidenced by increased GMP and disulfide bond content (reaching a maximum at 80 °C), which improved the texture and cooking properties. Hence, the water mobility was effectively reduced by controlling the drying temperature. The temperature had a facilitating impact on promoting the aggregation of the gluten network structure, which improved the quality of the instant dough sheets.

Impacts of washing and deodorization treatment on packaging-sourced post-consumer polypropylene

AbstractEmerging legal requirements will likely considerably heighten demand for high-quality recycled raw materials for e.g., packaging and automotive applications; key EU legislation mandates recycling as the future end-of-life option for municipal solid plastic waste. Yet recycled plastic use remains low due to safety concerns, undesirable aesthetic, olfactory, and mechanical properties, mainly attributable to contaminants present in recyclates. Advanced treatment options for recovered polypropylene (PP) packaging and the impact of such treatments on the polymer are currently poorly documented. We investigated the effectiveness of hot/cold washing and hot air devolatilization treatments in removing volatile substances from residential post-consumer PP plastic waste to improve its scope of application and value and to assess possible side effects on mechanical and processing parameters. Cold- and hot-washed recyclates exhibited similar contaminant levels and most substances were removed within 7 h. The recycling procedure had no adverse effects on mechanical or processing parameters although reprocessing caused polymer degradation, indicated by decreasing viscosity, elongation at break, and tensile strength. Washing and hot air devolatilization treatment of plastic wastes improve their scope of application and value by enhancing mechanical properties and considerably reducing the amounts of odorous substances, but is often not suited to high-quality applications, such as packaging. The dominance of packaging waste and strict legislation on food-grade recyclate applications will make widespread recyclate use challenging since it represents the primary use of plastic. Recyclate must consequently be extensively utilized in non-food contact applications until advances in waste sorting, washing, and devolatilization yield less contaminated recyclates with improved properties.

Bankruptcy Prediction and Performance: the Influence of Quality Certification on Portuguese SMEs

Objective: To observe the existence of a relationship between quality certification and performance and bankruptcy prediction for Portuguese SMEs. Theoretical Reference: The search for quality and its certification, via the International Standard Organization (ISO), theoretically, is related to the going concern assumption, making it possible to enhance the company's economic and financial sustainability. Method: Multisectoral Multivariate Discriminant Analysis (ADM) models, considered the most efficient, were selected for application, as well as the commonly used Univariate Analysis indicators. In Bureau Van Dijk's SABI Database, we collected Portuguese SMEs, with financial information from 2014 to 2018, certified in the scope of quality, ISO 9000 or 9001, on 12/31/2018, of these, we focused on those with main activity in NACE D - Electricity, Gas, Steam, Hot and Cold Water and Cold Air or G - Wholesale and Retail Trade, Repair of Motor Vehicles and Motorcycles as they are the most important. The Sector Average Company was also collected for the same NACE via Banco de Portugal Sector Tables. Then, having applied the models and indicators under study, we compared the results obtained between them, in order to observe the possible effect of quality certification on financial performance. Results and Discussion: No implication of quality certification in improving or optimizing the performance or economic-financial position of entities is identified. Implications of the Research: Uncover the influence of quality certification on the economic-financial position of companies, allowing for deeper investigation into bankruptcy, sustainability and value creation. Originality/Value: The specificities of the sectors and business size, crises and increasing closures make it vital to identify what will influence performance and sustainability, as no studies have been identified on this topic, focusing on Portuguese SMEs, certified via ISO 9000 or 9001.