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Introduction Heat treatment is a routine operation in food production since it effectively destroys microorganisms that cause spoilage in food, thereby increasing the shelf life of products. At the same time, high temperatures may have a negative

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Abstract  

Heat treatment of pipes was performed under industrial conditions at 580C in a dry protective gas containing a CO2–CO–H2–N2 mixture. A commercial adsorbent (733 kg) used for production ofthe gas removed 52.7 l of water in five h and 22.5 min. During the annealing of pipesoxidation and decarburization were not observed. The results were confirmed bymetallographic analysis. The values of enthalpy of water desorption (36.4–40.5 kJ mol–1) obtained by DSC and TG measurements were close to those of water evaporation(44.1 kJ mol–1). This suggests that the bonds between the water molecules andadsorbents were not of chemical but of physical nature.

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Progress in Agricultural Engineering Sciences
Authors: Emna Ayari, Csaba Németh, Karina Ilona Hidas, Adrienn Tóth, Dávid Láng, and László Friedrich

products because they are easy to handle. Microbiological safety of liquid products is mainly guaranteed by pasteurization ( Lechevalier et al., 2017 ). Consequently, there are many standardizations of the heat-treatment. The USDA requires liquid egg

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Acta Alimentaria
Authors: L. Silva, G. Maia, P. Sousa, R. Figueiredo, M. Afonso, M. Gonzaga, C. Gomes, and E. Figueiredo

The purpose of this experiment was to evaluate the effect of heat treatment on the rheological properties of mixed nectars, based on cashew apple, mango, and acerola pulps. Ten different formulations with different mass fractions of cashew apple, mango, and acerola pulps were prepared using a simplex centroid design [with a total of 35% (w/w) pulp] and submitted to heat treatment at 90 °C for 1 min. Samples were collected before and after heat treatment and characterization of their rheological properties was carried out. The rheological behaviour was obtained at 25 °C, with shear rate ranging from 108 to 500 s−1 (upward curve) and from 500 to 108 s−1 (downward curve) for 1 min with 25 readings for each curve. The Ostwald de Waele model showed to be a good fit for all formulations studied, which showed a non-Newtonian behaviour and a pseudoplastic character. Results of apparent viscosity for the non-heated formulations were well fitted by the linear model and the heat treated formulations by the cubic model. The heat treated formulations had higher (P<0.05) values of consistency index and apparent viscosity, as well as lower (P<0.05) values of flow behaviour index compared to non-heated formulations. The rheological characterization of these formulations is a very useful tool during product development and processing control of mixed nectars of fruit juice.

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., 2009; Kaszab et al., 2017 ). The properties of honeys also vary according to their exposure to heat. Heat treatment of the honey can influence its composition and physicochemical properties ( Bodor et al., 2019; Božiková et al., 2018 ). The proper

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for a proper choice of the heat-treatment temperature and time to keep the powder's grain size at nanometric level, but stress free. Indeed, it has been reported that the thermal stability of the nanocrystalline materials depend on the particle size

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structure [ 18 , 19 ]. The synthesis of the copper ferrite was achieved by mechanical milling of the precursors oxides followed by annealing treatment [ 20 ]. This article presents results of the investigation of the influence of the heat treatments

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especially Salmonella and Listeria monocytogenes ( Baron et al., 2010 ). Pasteurization temperatures used in the egg industry are limited by the sensitivity of egg proteins to heat treatment. Thus, pasteurization for 2–10 min from 60 to 68 °C modifies

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substitute heat treatment to preserve food products, as it inactivates vegetative microorganisms, spores, and enzymes as well, thus increases shelf-life, in case of fruits and vegetables up to 4–6 weeks with refrigeration storage ( Matser and Timmermans, 2016

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Journal of Thermal Analysis and Calorimetry
Authors: M. Kubota, Y. Kanazawa, K. Nasu, S. Moritake, H. Kawaji, T. Atake, and Y. Ichiyanagi

Abstract  

MgFe2O4 (Mg-ferrite) nanoparticles encapsulated in amorphous SiO2 were prepared by the wet chemical method. The particle sizes were estimated, based on the X-ray diffraction peaks, to be between 3 and 8 nm, depending on the annealing temperature. The particle size increased as the annealing temperature increased. From the magnetization measurements, the blocking temperature, T b, was found to be between 30 and 60 K. The magnetization values varied with the annealing or quenching conditions. To clarify the process of crystal growth, thermogravimetric and differential thermal analysis (TG-DTA) measurements were performed and the results were compared with the X-ray diffraction patterns.

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