Analyzing the physical and biochemical changes in strawberries during storage at different temperatures and the development of kinetic models

Author(s):  
Abhijeet B. Muley ◽  
Priya Kedia ◽  
Kakoli Pegu ◽  
Shankar B. Kausley ◽  
Beena Rai
2018 ◽  
Vol 12 (1) ◽  
pp. 178-187
Author(s):  
Baghdad Science Journal

A new copolymer (MFA) was prepared from condensation of melamine (M) with p- methyl – anisole (A) in the presence of condensation agent like 37% (w/v) of formaldehyde. The new copolymer was characterized by elemental, IR and HNMR spectra. The chelating ion-exchange property of this polymer was studied for methylene blue dye in aqueous solution in 100-200ppm concentrations. The adsorption study was carried out over a wide range of pH, shaking time and in media of various kinetic parameters models. Thermal parameters like enthalpy, entropy and Gibbs free energy of adsorption process of methylene blue on surface of MFA resin were determined on the basis of kinetic parameters at different temperatures. To describe the equilibrium of adsorption, the Langmuir, Freundlich and Temkin isotherms were used. The Langmuir isotherm correlation (R2=0.987) was the best fitted for experimental data with maximum adsorption capacity of 200 ppm. A higher correlation value of the kinetic's model was observed close to pseudo first order, second order and Temkin kinetic models values of correlation R2 lie in the range (0.983-0.987) in comparing to other kinetic models.


Agronomy ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2185
Author(s):  
Rosnah Shamsudin ◽  
Siti Hajar Ariffin ◽  
Wan Nor Zanariah Zainol @Abdullah ◽  
Nazatul Shima Azmi ◽  
Arinah Adila Abdul Halim

Dabai (Canarium odontophyllum Miq.) is a fruit that is often eaten by first blanching in hot water to make the flesh creamier and softer, before it is served as a snack or side dish. In this study, Dabai fruit was blanched at different temperatures between 60 and 100 °C, with an increment of 10 °C, for up to 10 min, and the kinetics of quality changes (color and texture) were studied. Kinetic models that were assessed for changes of color and texture were zero-order, first-order, and fractional conversion model. The results showed that L parameter had no change throughout the blanching process, while parameters a*, b*, chroma (C), and total color difference (TCD) resulted as significantly increased as the temperature and duration of blanching increased. However, the change of firmness was not significant due to minor changes of firmness as the temperature and time increased. In terms of kinetic models, zero and fractional-conversion order well described the changes of a* parameter; while zero, first and fractional conversion well described parameters b*, C and TCD. Change of firmness did not fit with zero or first-order. All of the kinetic models obeyed the Arrhenius equation. Thus, the fitted kinetic models can be used to design the blanching process of Dabai fruit.


2018 ◽  
Vol 172 (2) ◽  
pp. 522-543 ◽  
Author(s):  
E. A. Carlen ◽  
R. Esposito ◽  
J. L. Lebowitz ◽  
R. Marra ◽  
C. Mouhot

2021 ◽  
Vol 42 (5) ◽  
pp. 2685-2702
Author(s):  
Altamara Viviane de Souza Sartori ◽  
◽  
Carolina Maria Gaspar de Oliveira ◽  
Claudemir Zucareli ◽  
◽  
...  

The black oat (Avena strigosa Schreb.) stands out as a forage of great importance in Brazilian agriculture. However, the productivity and quality of this forage can be affected by abiotic factors, such as temperature and water availability, which affect the physiological processes and facilitate the accumulation of free radicals (reactive oxygen species - ROS). Thus, the objective of this study was to understand the biochemical changes in black oat plants subjected to water deficit at different temperatures. Experiments were conducted in a greenhouse in two experimental periods, which presented an average temperature of 20 °C and 24 °C, respectively. Black oat seeds, of the variety IAPAR 61, were sown in pots and the plants were irrigated for 60 days. After which, the pots were covered with plastic bags and the irrigation was suspended. The analyses were carried out in five periods of evaluation - M1: plants before the suspension of irrigation, M2: plants at the first wilting point, M3: three days after plastic removal and irrigation return, M4: four days after M3 and before the second suspension of irrigation, and M5: the second wilting point. The levels of total protein and malondialdehyde (MDA), and the activity of the enzymes catalase (CAT) and ascorbate peroxidase (APX), were analyzed. The experimental design was completely randomized, with six replications, in a factorial scheme of average temperature × water management × periods of evaluation, and the means were compared by Tukey’s test at 5%. In response to water deficiency and temperature increase, black oat plants increased their levels of total soluble proteins, and there was greater lipid peroxidation due to the increase in malondialdehyde content. There was no change in the activity of the enzymes catalase and ascorbate peroxidase under water deficit, and these activities decreased with increasing temperature.


Author(s):  
Chuanqi Yan ◽  
Quan Lv ◽  
Allen A. Zhang ◽  
Changfa Ai ◽  
Weidong Huang ◽  
...  

1981 ◽  
Vol 7 (3) ◽  
pp. 189-193 ◽  
Author(s):  
D TONELLI ◽  
E GATTAVECCHIA ◽  
R BUDINI

2019 ◽  
Vol 50 (3) ◽  
Author(s):  
João Paulo Nobre de Almeida ◽  
Emanoela Pereira de Paiva ◽  
Salvador Barros Torres ◽  
Francisco Vanies da Silva Sá ◽  
Moadir de Sousa Leite

Minerals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1065
Author(s):  
Lidia Reczek ◽  
Magdalena M. Michel ◽  
Yuliia Trach ◽  
Tadeusz Siwiec ◽  
Marta Tytkowska-Owerko

The study aimed to determine the nature of the kinetics of the manganese sorption process on Ukrainian tuff and basalt at different temperatures characteristic of the natural water environment. The scope of the research included manganese sorption kinetic test on natural mineral sorbents at temperatures of 10, 17.5 and 25 °C in slightly acidic conditions. Sorption (pseudo-first order, pseudo-second order and Elovich models) and diffusion kinetic models (liquid film diffusion and intraparticle diffusion) were used in the analysis of test results. The manganese sorption process on both tuff and basalt proceeded quickly. The dynamic equilibrium state of manganese sorption settled after 35 and 45 min on tuff and basalt respectively. Although the process took place in a slightly acidic environment and below pHPZC of the sorbents, possible electrostatic repulsion did not inhibit the removal of Mn. The Mn sorption on both materials followed the PSO kinetics model. Based on the diffusion kinetic models, it was determined that Mn sorption process on both materials was influenced by diffusion through the boundary layer and intraparticle diffusion. The differences in removal efficiency and rate of Mn sorption in the temperature range of 10–25 °C were not found.


Author(s):  
J. L. Brimhall ◽  
H. E. Kissinger ◽  
B. Mastel

Some information on the size and density of voids that develop in several high purity metals and alloys during irradiation with neutrons at elevated temperatures has been reported as a function of irradiation parameters. An area of particular interest is the nucleation and early growth stage of voids. It is the purpose of this paper to describe the microstructure in high purity nickel after irradiation to a very low but constant neutron exposure at three different temperatures.Annealed specimens of 99-997% pure nickel in the form of foils 75μ thick were irradiated in a capsule to a total fluence of 2.2 × 1019 n/cm2 (E > 1.0 MeV). The capsule consisted of three temperature zones maintained by heaters and monitored by thermocouples at 350, 400, and 450°C, respectively. The temperature was automatically dropped to 60°C while the reactor was down.


Sign in / Sign up

Export Citation Format

Share Document