Types Of Thermal Treatment Research Articles

Sweet Potatoes Puree Mixed with Herbal Aqueous Extracts: A Novel Ready-to-Eat Product for Lactating Mothers

Worldwide, around 385 thousand babies are born each day. Many of them cannot be breastfed because of several physiological problems of the mothers. Galactogogues remain the most natural and prolific way to improve both milk quantity and quality. Various herbs are traditionally used to increase lactation, but the best known are fennel (Foeniculum vulgare L.) and anise (Pimpinella anisum L.). The main objective of the present study was to obtain some special and nutritious ready-to-eat products from pureed sweet potato (Ipomoea batatas L.) fortified with aqueous extracts from the aforementioned galactogogues herbs. Two different types of thermal treatment, steaming and baking, were investigated to obtain healthy and safe-for-consumption purees. Steam convection had a lower impact, compared with hot air convection, on the content of bioactive compounds among all samples. Among all samples, sweet potato puree with fennel aqueous extract, processed by steaming, (EFCA) showed the highest content of β-carotene (1.27 ± 0.11 mg/g DW), lycopene (0.59 ± 0.07 mg/g DW), and total carotenoids (1.38 ± 0.11 mg/g DW); the cooking loss registered statistically significantly lower values in the case of steam convection. These reports might potentially generate novel ready-to-eat foods used as meals and as well as lactation adjuvants.

Effect of thermal treatments (roasting, microwaving, steaming) on anti-nutritional factors and physical and antioxidant properties of black gram (Vigna cylindrica L. Skeels)

The aim of this research was to investigate the effect of thermal treatments, including roasting, microwaving, and steaming, on anti-nutritional factors and physical and antioxidant properties of black gram (Vigna cylindrica L. Skeels). Regarding its physical properties, thermal treatment increased the water-holding capacity (WHC) and decreased the oil-holding capacity (OHC) of the black gram samples. No significant difference was observed between the roasted sample and the control. Regarding the chemical properties, anthocyanins accounted for the vast majority of total phenolic content (TPC). The steamed sample had the lowest TPC and anthocyanin values, which were 272.46 mg/100 g dry basis and 121.20 mg/100 g dry basis, respectively. Among the three types of thermal treatments, roasting resulted in the highest TPC content, which was 424.35 mg/100 g dry basis. Particularly, the steaming treatment led to the lowest anthocyanin content and antioxidant capacity (AC) in the flour sample; furthermore, there were no significant differences in the TPC and AC values between the microwaved and roasted samples. The phytate content was significantly reduced in all heat-treated samples and there were no significant differences among these cooked samples. The tannin content of the steamed sample was recorded to be the lowest, which was 164.19 mg/100 g dry basis. In summary, roasting, microwaving, and steaming significantly influenced the nutritive values of black gram (Vigna cylindrica L. Skeels).

The effect of heat treatment on bioactive compounds and color of selected pumpkin cultivars

In this study, the effect of selected thermal operations applied during processing of pumpkins of the cultivar Butternut Rugosa of the species Cucurbita moschata as well as hybrid grey pumpkin Nelson F1 and Hokkaido ‘Uchiki Kuri’ of the species Cucurbita maxima on the presence of selected bioactive compounds (gallic acid, quercetin, cyanidin 3-glucoside, l-ascorbic acid) and color expressed in CIE L*a*b* chromatic and L*C*H* cylindrical color spaces was evaluated. The highest content of polyphenols (13.296 mg(GAE)/g f.w.), flavonoids (0.732 mg(KW)/g f.w.) and l-ascorbic acid (19.38 mg (L-AA)/100 g f.w.) was found in Hokkaido cv. Uchiki Kuri (Cucurbita maxima), while the lowest content of these compounds was found in Butternut Rugosa (Cucurbita moschata). The analysis of the results showed that immersion cooking was the least favorable thermal treatment because of the loss of bioactive compounds up to 80% and that steam cooking was more favorable. It was also shown that blanching before freezing of pumpkins is advantageous from the point of view of minimization of nutrient losses. Despite the fact that pumpkins underwent different types of thermal treatment, their color was still characterized by orange shade with higher or lower saturation depending on the variety.

Studying an effect of thermal treatment methods on physico-chemical properties of beef depending on aging technology

Modern methods for aging and thermal treatment facilitate an improvement in beef sensory properties. The aim of the research was to study an effect of different types of thermal treatment on quality of steaks from dry-aged beef. Steaks were obtained from the rib cut from carcasses of grain-fed young bulls; aging duration was 35 days (temperature 0–1 ºС, air relative humidity 74–75%). Aging duration in the control sample was five days (temperature 0–4 ºС, air relative humidity 80–85%). The methods for thermal treatment were as follows: sous vide cooking at 58 ºС, grill heating at 250 ºС, sous vide cooking in combination with grill treatment. During processing, the following parameters were controlled: weight loss by the direct method, hydrophobicity of myofibrillar proteins by the reaction with bromophenol blue, soluble collagen by the method of acid hydrolysis with determination of oxyproline, mass fraction of moisture and fat by the method from one analytical unit, sensory properties by the reference method. According to the data obtained, minimal losses (6.8%) were noticed upon sous vide cooking of dry-aged beef steaks. In combined heating and dry heating on grill, they increased by 6.1% and 12%. More significant weight losses were observed in beef steaks with aging time of five days upon any tested treatment types. For dry-aged beef steaks treated by sous vide and combined heating, a higher content of soluble collagen compared to other samples was established. The results of measuring mass fraction of moisture and fat indicate an increase in the nutritional value of dry-aged beef steaks. According to the total data obtained with consideration for the results of sensory evaluation, dry-aged beef steaks subjected to sous vide cooking with the following short-term dry heating on grill have higher quality.

Metabolomics elucidating the effect of water activity on the thermal resistance of Salmonella in wheat flour

With mounting evidence indicating an enhanced thermal resistance of Salmonella at lower aw, the effectiveness of thermal treatment in wheat flour decontamination is challenged. Therefore, this study was carried out to evaluate the thermal resistance of three Salmonella strains, including Enteritidis (ATCC 13076), Typhimurium (ATCC 14028) and Newport (ATCC 6962), at 65 °C in wheat flour at three aw levels (0.33, 0.53 and 0.69), and to explore the mechanisms of the difference in thermal resistance via nuclear magnetic resonance (NMR)-based metabolomics. The results showed that except for the insignificant difference between the reductions of S. Newport at 0.53 and 0.69 flour aw (P > 0.05), a remarkable decreasing trend in Salmonella cell reduction with decreasing flour aw was observed after the 20-min thermal treatment. By comparing the metabolic profiles of each strain recovered from the lower-aw (0.33 or 0.53) flour with that from the aw-0.69 flour, the metabolic differences implying more efficient misfolded protein degradation, higher availability of amino acids as osmoprotectants, larger throughput of energy production by ATP synthase as well as wiser glucose allocation in the metabolic network were suspected to contribute to the strains’ enhanced thermal resistance. Overall, the study adds to the evidence for the effect of lower aw in increasing the thermal resistance of Salmonella in wheat flour. Meanwhile, the identified discriminative metabolic pathways may be artificially modified in the future to help ease Salmonella inhibition during cooking or any types of thermal treatments.

Influence of various heat treatments on fatigue crack growth in 42CrMo4 steel under mixed modes I + II and I + III

The article addresses the results of the study of the examination of fatigue fracture in mixed and I + II and I + III modes in heat treated steel 42CrMo4. Three types of thermal treatments were performed, each caused various mechanical properties of the material. Tests were performed on two sample types: compact tension specimen (CTS) and rectangular cross-sectional samples for mixed mode and I + III. Mixed mode I + II tests were performed for 30 and 60° load angles while the mixed mode test I + III was carried out for 30 and 45°. In addition, the paper shows crack paths for all cases tested. Presented research aims to expand the knowledge of fatigue crack development under mixed mode while taking into consideration different mechanical properties of the same composition-wise material. The aforementioned knowledge is a significant contribution to defining the material fatigue under complex load, independently to sample geometry and number of other limitations.

Effect of thermal treatment on the physical properties of GG100 clone Eucalyptus wood

Thermal treatment can modify undesirable characteristics of some woods, dimensional instability, and excessive water adsorption. The present research work aimed to assess the effect of thermal treatment on the physical properties of clone GG100 Eucalyptus wood. Wood samples were obtained from 9 year-old trees. Samples were subjected to three types of thermal treatment (T1, T2, and T3). In T1, the wood was kept in a laboratory kiln at 100 °C for 180 min. In T2, hydrothermal treatment was performed in an autoclave at 120 °C for 120 min. In T3, the combined autoclave and laboratory kiln treatments were employed. The properties evaluated were apparent density (ρa); mass loss (ML); longitudinal (βl), radial (βr), tangential (βt), and volumetric shrinkage (βv); anisotropic factor; and equilibrium moisture content. The treatments caused a decrease of ρa and increase of ML. The Equilibrium Moisture Content (EMC) was lowest for T3, and had a negative correlation with ML, βt, and ∆v. The Pearson correlation analysis indicated the results of the thermal treatments were similar, but T1 presented the lowest variation of the physical properties compared to the other treatments, giving it the best predictability for practical uses.

Exploring volatile organic compound emission from thermally modified wood by PTR-ToF-MS.

Thermal modification of wood is a well-known industrial process performed to increase the durability and dimensional stability or to change the colour of natural wood. The treatment influences many other properties of wood including the emission of volatile organic compounds (VOCs). VOC release ultimately affects the quality of indoor air and the capability of having low VOC emission is often included as a key parameter for the attribution of quality labels. In the present work, wood from six tree species was subjected to different types of treatment and VOC profiling was carried out on both treated and untreated samples by means of PTR-ToF-MS. Different types of thermal treatment were tested, involving either overpressure or vacuum and the effect of different temperature profiles was evaluated. Hardwood and softwood showed different release profiles under all tested conditions: the headspace of softwood was richer in several VOCs, such as terpenes, phenols and C6-C9 aldehydes and carboxylic acids. Upon thermal treatment, terpene emissions decreased, whereas several other VOCs, such as formic acid, formaldehyde, furfural and acetic acid, were released in higher amounts. With its high sensitivity and throughput, PTR-ToF-MS appears to be a very powerful analytical tool, useful in supporting the selection of wood materials for different end uses.

High-entropy alloys: Structure, mechanical properties, deformation mechanisms and application

The article considers a brief review of the foreign publications on the study of the structure, phase composition and properties of five-component high-entropy alloys (HEAs) in different structural states in a wide temperature range over the past two decades. HEAs attract the attention of scientists with their unique and unusual properties. The difficulties of comparative analysis and generalization of data are noted due to different methods of obtaining HEAs, modes of mechanical tests for uniaxial compression and tension, sizes and shapes of the samples, types of thermal treatments, and phase composition (bcc and fcc crystal lattices). It is noted that the HEA with a bcc lattice has mainly high strength and low plasticity, and the HEA with a fcc lattice has low strength and increased plasticity. A significant increase in the properties of the FeMnCoCrNi HEA with a fcc lattice can be achieved by alloying with boron and optimizing the parameters of thermal mechanical treatment at alloying with carbon in the amount of 1 % (at.). The deformation curves analyzed in the temperature range –196 ÷ 800 °C indicate an increase in the yield strength with a decrease in the grain size from 150 to 5 microns. As the temperature decreases, the yield strength and elongation increase. The effect of deformation rate on the mechanical properties is an increase in the ultimate strength and yield strength, which is most noticeable at high rates of 10–2 ÷ 103 s–1. The features of HEAs deformation behavior in the mono- and poly-crystalline states are noted. The complex of high operational properties of HEAs makes it possible to use them in various industries. There are good prospects of using energy treatment to modify the surface layers and further improve HEAs properties.

Degradation of Fatty Acid Phase-Change Materials (PCM): New Approach for Its Characterization

The use of adequate thermal energy storage (TES) systems is an efficient way to achieve thermal comfort in buildings reducing the cooling and heating demand. Besides, deploy phase change materials (PCM) to meet and enhance the TES needs is highly effective and widely studied. In this paper, a study of the degradation of two fatty acids is presented, capric and myristic acids, in order to evaluate whether their thermo-physical properties are affected throughout time during service. This was carried out by means of two different types of thermal treatments: degradation at constant temperature (thermal stability test), 60 °C during 100 h and 500 h, and degradation with heating and cooling cycling (thermal cycling stability), between a temperature range from 15 °C to 70 °C with 0.5 °C/min ramp during 500 and 1000 cycles. Despite no significant changes were measured for myristic acid, experimental results revealed a decrease of melting enthalpy of 6.6% in capric acid thermally treated for 500 h. Evidences of chemical degradation were found that might explain the decrease in thermophysical properties during use.

The changes in the amino and fatty acid profiles in the semifinished foodstuffs based on broiler meat and components of chicken eggs after different types of thermal treatment

The changes in the amino and fatty acid profiles in the semifinished foodstuffs (SFFs) based on broiler meat and coagulated chicken egg melange after different types of thermal treatment (water or steam boiling, braising, baking, frying) were studied. The amino acid profiles were determined on Knauer analyzer; tryptophan by standard method. The biological value of the treated products was assessed using amino acid balance coefficients calculated by the method of N. N. Lipatov. It was found that the changes in the initial amino acid profiles of the SFFs were the least after water and steam boiling; braising and baking were found to increase the contents of the essential amino acids. The amino acid profiles in the treated SFFs were close to the reference values. The best criteria of their biological value (coefficient of rationality of amino acid composition, comparable redundance) were found after water and steam boiling. It was found that all types of thermal treatments insignificantly affected the parameters of fatty acid balance within the SFFs; the changes found were primarily related to slight increase in total content of saturated fatty acids and increase in total content of polyunsaturated fatty acids (PUFAs) in compare to initial profiles, by 2.64–3.88% depending on the treatment type. The changes in ω‑6/ω‑3 PUFAs ratios were more substantial especially after braising

Magnetic properties in rapid current annealed Fe85.2Si0.5B9.5P4Cu0.8 (NANOMET) ribbon

Fil: Moya, Javier Alberto. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Tecnologias y Ciencias de la Ingenieria Hilario Fernandez Long. Grupo Vinculado al Intecin - Grupo Interdisciplinario en Materiales; Argentina

Дослідження процесу пропарювання букових заготовок і пиломатеріалів

Зменшити втрати деревини від грибкових пошкоджень під час зберігання і транспортування можна завдяки проведенню теплової стерилізації. Теплову обробку деревини використовують у багатьох деревообробних процесах: виробництво лущеного і струганого шпону, у лісопильному виробництві, процесах гнуття та пресування. Одним із видів теплової обробки деревини є пропарювання. Відсутність процесу пропарювання букових пиломатеріалів після лісопилення є причиною значних втрат деревини від розтріскування, враження грибами та комахами. У виробничих умовах, під час пропарювання, не враховують багато чинників: особливостей будови деревини бука, її густини, теплових та механічних властивостей. Все це призводить до зайвих втрат матеріалу, теплової енергії та якісних показників букових пиломатеріалів. Тому дуже важливо досліджувати режими та технології пропарювання букових пиломатеріалів із збереженням їх фізико-механічних властивостей. Дослідження проведено з використанням пропарювального ковпака виробничого зразка. Здійснено експериментальні дослідження пропарювання букових заготовок та пиломатеріалів, яке охоплює початковий прогрів, сам процес пропарювання та охолодження. Внаслідок проведення експериментальних досліджень вибрано оптимальні режими пропарювання, які зберігають якісні фізико-механічні показники, такі як: запобігання втратам деревини під час зберігання і транспортування, вирівнювання забарвлення або надання деревині потрібного кольору, покращення міцності та пластичності, прискорення подальшого сушіння.

The Hardening in Alloys and Composites and Its Examination with a Diffraction and Self-Consistent Model

Abstract The paper presents the results of diffraction stress measurement in Al/SiC composite and in 2124T6 aluminum alloy during the in situ tensile test. The main aim of the work is to observe the stress values for different stages of tensile test for the composite after applying two types of thermal treatment and for the alloy used as a matrix in this composite, to identify the type of hardening process. The experimental results were compared against the calculations results obtained from the self-consistent model developed by Baczmański [1] - [3] to gain the information about the micromechanical properties (critical resolved shear stress τcr and hardening parameter H) of the examined materials. This comparison allowed researchers to determine the role of reinforcement in the composite as well as the impact of the heat treatment on the hardening of the material.

The Influence of Severe Plastic Deformation Process on Structure and Properties of AZ 31 Alloy after Selected Heat Treatment

The technology of structure refinement in materials with the aim of achieving substantial mechanical properties and maintaining the required plasticity level is becoming increasingly useful in industrial practice. Magnesium alloys are very progressive materials for utilization in practice thanks to their high strength-to-weight ratios (tensile strength/density). The presented paper analyses the effect of the input heat treatment of the AZ31 alloy on the change of structure and strength properties through the process of severe plastic deformation (SPD), which finds an increasing utilization, especially in the automotive and aviation industry. For the study of the influence of the SPD process (ECAP method) on the properties of the AZ31 alloy, two types of thermal treatment of the initial state of the structure were selected. The analysis of the structure of the AZ31 alloy was performed in the initial state without heat treatment and subsequently after heat treatment. In the next part, the influence of the number of passes on the strengthening curves was evaluated. Mechanical properties of the AZ31 alloy after ECAP were evaluated by hardness measurement and completed by structure analysis.

Relationship between the carbon nano-onions (CNOs) surface chemistry/defects and their capacitance in aqueous and organic electrolytes

The effect of surface functionalities on the supercapacitors performances has been highlighted often in many works. However, studies devoted to the influence of carbon defects did not gain particular attention due to the difficulty to quantify such parameter. In this context, carbon nano-onions were used as model material in order to understand the influence of the surface chemistry (nature and amount of oxygen groups) and structural defects (active surface area, ASA) on the capacitance. Different types of thermal treatments in oxidizing or reducing atmospheres allowed to finely tune the surface chemistry and the ASA as demonstrated by temperature programmed desorption coupled with mass spectrometry (TPD-MS). For the first time, the presice control of these characteristics independently one of each other allowed to highlight an important influence of the carbon defects on the capacitance in organic and aqueous electrolytes which outbalance the oxygen functional group effect.

Environmental Friendly Ways to Generate Renewable Energy from Municipal Solid Waste

Economic growth and rapid urbanization are resulting into increase in generation of municipal solid waste (MSW). In India, approximately 68 MT of MSW generated annually in urban areas and more than 80% is disposed in unhygienic manner leading to problems of health and environment to inhabitants. To manage MSW, there is a need to plan infrastructure development. There are many technologies available for handling MSW which treat plastic to convert fuel oil by gasification, pyrolysis, biomethanation and catalytic conversions. The useful products like liquid fuels, chemicals and power are being generated through these processes.The final products need to comply with environmental regulations and demand a lot of technological improvement. Based on MSW/feed quality, there is a need to identify the suitable technology for converting MSW into useful products, which can meet the statuary regulations. Hence, treating MSW, converting into useful products and selection of suitable technology is a big challenge.The present paper focuses to compare:•All suitable treatment technologies and products generated from MSW.•Types of thermal treatments like combustion/incineration, gasification and pyrolysis.It also highlights development of a systematic approach to comply with all environmental regulations to create value for all types of MSW and reduce landfill.

Estabilidade de Minerais em Hortaliças Submetidas a Diferentes Métodos de Cozimento

The aim of this study was to verify the more appropriate cooking method in vegetables preparation, aiming to minimize the minerals losses. Conventional and unconventional shares of pumpkin, broccolis, carrot and cauliflower were subjected to four types of thermal treatments (immersion, steam, pressure and microwaves). Mineral analyses (Fe, Zn, Mg, K, P e Ca) it was accomplished in the fresh vegetable and after cooking for the different methods in study. The minerals content was higher or similar to the conventional parts of the appraised vegetables. The mineral losses occurred in their conventional and unconventional parts in relation to the fresh vegetable after they were subjected to the cooking methods. The cooking method to steam and in microwaves resulted in the smallest minerals losses.

LCA of management strategies for RDF incineration and gasification bottom ash based on experimental leaching data

The main characteristics and environmental properties of the bottom ash (BA) generated from thermal treatment of waste may vary significantly depending on the type of waste and thermal technology employed. Thus, to ensure that the strategies selected for the management of these residues do not cause adverse environmental impacts, the specific properties of BA, in particular its leaching behavior, should be taken into account. This study focuses on the evaluation of potential environmental impacts associated with two different management options for BA from thermal treatment of Refuse Derived Fuel (RDF): landfilling and recycling as a filler for road sub bases. Two types of thermal treatment were considered: incineration and gasification. Potential environmental impacts were evaluated by life-cycle assessment (LCA) using the EASETECH model. Both non-toxicity related impact categories (i.e. global warming and mineral abiotic resource depletion) and toxic impact categories (i.e. human toxicity and ecotoxicity) were assessed. The system boundaries included BA transport from the incineration/gasification plants to the landfills and road construction sites, leaching of potentially toxic metals from the BA, the avoided extraction, crushing, transport and leaching of virgin raw materials for the road scenarios, and material and energy consumption for the construction of the landfills. To provide a quantitative assessment of the leaching properties of the two types of BA, experimental leaching data were used to estimate the potential release from each of the two types of residues. Specific attention was placed on the sensitivity of leaching properties and the determination of emissions by leaching, including: leaching data selection, material properties and assumptions related to emission modeling. The LCA results showed that for both types of BA, landfilling was associated with the highest environmental impacts in the non-toxicity related categories. For the toxicity related categories, the two types of residues behaved differently. For incineration BA the contribution of metal leaching to the total impacts had a dominant role, with the highest environmental loads resulting for the road scenario. For the gasification BA, the opposite result was obtained, due to the lower release of contaminants observed for this material compared to incineration BA. Based on the results of this study, it may be concluded that, depending on the type of BA considered, its leaching behavior may significantly affect the results of a LCA regarding its management strategies.

Influence of Heat Treatment on Values of a Strain of Interstitial Free Steel

This study aimed to investigate how the heat treatment can influence the strain values ​​of an IF steel observing the different values ​​of the tensile, rupture and drain that were recorded during the tensile test. We analyzed five samples of the specimen (CP) using different combinations of heat treatments to enable evaluation of the behavior of material deformation by tensile test. The evaluation was performed using the deformation calculation of the ratio between the axial and radial deformations (anisotropy parameter). The results indicate how different types of thermal treatments influenced in their initial properties, generating materials with different characteristics.