Assessment of the Starch-Amylolytic Complex of Rye Flours by Traditional Methods and Modern One

The properties of the starch-amylolytic complex of commercial low-extract rye flour were determined based on the traditional method, such as falling number and amylograph test as well as differential scanning calorimetry (DSC). The starch, pentosans and protein had a significant effect on the thermal properties of the tested rye flours. Based on the falling number, it was revealed that rye flours were characterized by medium and low alpha-amylase activity. The falling number and amylograph test are not sufficient methods to determine the suitability of currently produced rye flours for bread making. The gelatinization process of the rye flour starch could be evaluated by the DSC test, which, together with the falling number and amylograph test, may allow a better way to evaluate the usefulness of rye flours for bread making. Many significant correlations between parameters determined by DSC endotherm and quality parameters of rye bread, such as volume and crumb hardness, were reported. Breads made from flour with higher enthalpy in DSC were characterized by higher volume and softer crumb.

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Improved Processing and Properties for Polyphenylene Oxide Modified by Diallyl Orthophthalate Prepolymer

Polymers ◽

10.3390/polym11122016 ◽

2019 ◽

Vol 11 (12) ◽

pp. 2016

Author(s):

Honghua Wang ◽

Qilin Mei ◽

Yujie Ding ◽

Zhixiong Huang ◽

Minxian Shi

Keyword(s):

Differential Scanning Calorimetry ◽

Thermal Properties ◽

Phase Separation ◽

Dilution Effect ◽

Gradual Decrease ◽

Gel Point ◽

Dynamic Mode ◽

Curing Process ◽

Scanning Calorimetry ◽

Polyphenylene Oxide

Diallyl orthophthalate (DAOP) prepolymer was investigated as a reactive plasticizer to improve the processability of thermoplastics. The rheology of blends of DAOP prepolymer initiated by 2,3-dimethyl-2,3-diphenylbutane (DMDPB) and polyphenylene oxide (PPO) was monitored during the curing process, and their thermal properties and morphology in separated phases were also studied. Differential scanning calorimetry (DSC) results showed that the cure degree of the reactively plasticized DAOP prepolymer was reduced with increasing PPO due to the dilution effect. The increasing amount of the DAOP prepolymer led to a gradual decrease in the viscosity of the blends and the rheology behavior was consistent with the chemical gelation of DAOP prepolymer in blends. This indicated that the addition of the DAOP prepolymer effectively improved processability. The phase separation occurring during curing of the blend and the transition from the static to dynamic mode significantly influences the development of the morphology of the blend corresponding to limited evolution of the conversion around the gel point.

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An Undergraduate Experiment Using Differential Scanning Calorimetry: A Study of the Thermal Properties of a Binary Eutectic Alloy of Tin and Lead

Journal of Chemical Education ◽

10.1021/ed200450s ◽

2011 ◽

Vol 89 (4) ◽

pp. 548-551 ◽

Cited By ~ 5

Author(s):

Ronald P. D’Amelia ◽

Daniel Clark ◽

William Nirode

Keyword(s):

Differential Scanning Calorimetry ◽

Thermal Properties ◽

Eutectic Alloy ◽

Scanning Calorimetry ◽

Binary Eutectic

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Processing of (Co)Poly(2-oxazoline)s by Electrospinning and Extrusion from Melt and the Postprocessing Properties of the (Co)Polymers

Polymers ◽

10.3390/polym12020295 ◽

2020 ◽

Vol 12 (2) ◽

pp. 295 ◽

Cited By ~ 4

Author(s):

Wojciech Wałach ◽

Natalia Oleszko-Torbus ◽

Alicja Utrata-Wesołek ◽

Marcelina Bochenek ◽

Ewa Kijeńska-Gawrońska ◽

...

Keyword(s):

Differential Scanning Calorimetry ◽

Thermal Properties ◽

Molar Mass ◽

Three Dimensional ◽

Fused Deposition Modelling ◽

Processing Conditions ◽

Structure And Properties ◽

Scanning Calorimetry ◽

Gradient Copolymers ◽

Fused Deposition

Poly(2-oxazoline) (POx) matrices in the form of non-woven fibrous mats and three-dimensional moulds were obtained by electrospinning and fused deposition modelling (FDM), respectively. To obtain these materials, poly(2-isopropyl-2-oxazoline) (PiPrOx) and gradient copolymers of 2-isopropyl- with 2-n-propyl-2-oxazoline (P(iPrOx-nPrOx)), with relatively low molar masses and low dispersity values, were processed. The conditions for the electrospinning of POx were optimised for both water and the organic solvent. Also, the FDM conditions for the fabrication of POx multi-layer moulds of cylindrical or cubical shape were optimised. The properties of the POx after electrospinning and extrusion from melt were determined. The molar mass of all (co)poly(2-oxazoline)s did not change after electrospinning. Also, FDM did not influence the molar masses of the (co)polymers; however, the long processing of the material caused degradation and an increase in molar mass dispersity. The thermal properties changed significantly after processing of POx what was monitored by increase in enthalpy of exo- and endothermic peaks in differential scanning calorimetry (DSC) curve. The influence of the processing conditions on the structure and properties of the final material were evaluated having in a mind their potential application as scaffolds.

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Thermal Properties of the Starch/Water System Part I. Measurement of Heat of Gelatinisation by Differential Scanning Calorimetry

Starch - Stärke ◽

10.1002/star.19710230104 ◽

1971 ◽

Vol 23 (1) ◽

pp. 8-11 ◽

Cited By ~ 215

Author(s):

D. J. Stevens ◽

G. A. H. Elton

Keyword(s):

Differential Scanning Calorimetry ◽

Thermal Properties ◽

Water System ◽

Scanning Calorimetry ◽

System Part

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Brazilian gutta-percha points. Part II: thermal properties

Brazilian Oral Research ◽

10.1590/s1806-83242007000100005 ◽

2007 ◽

Vol 21 (1) ◽

pp. 29-34 ◽

Cited By ~ 8

Author(s):

Cláudio Maniglia-Ferreira ◽

Eduardo Diogo Gurgel-Filho ◽

João Batista Araújo Silva Jr ◽

Regina Célia Monteiro de Paula ◽

Judith Pessoa Andrade Feitosa ◽

...

Keyword(s):

Differential Scanning Calorimetry ◽

Thermal Properties ◽

Physical Properties ◽

Ambient Temperature ◽

Amorphous Phase ◽

Thermal Behaviour ◽

Chemical Structure ◽

Scanning Calorimetry ◽

Gutta Percha ◽

Thermal Manipulation

This study was undertaken to explore the effect of heating on gutta-percha, analyzing the occurrence of endothermic peaks corresponding to the transformation that occurs in the crystalline structure of the polymer during thermal manipulation. This study also seeked to determine the temperature at which these peaks occur, causing a transformation from the beta- to the alpha-form, and from the alpha- to the amorphous phase. Eight nonstandardized gutta-percha points commercially available in Brazil (Konne, Tanari, Endopoint, Odous, Dentsply 0.04, Dentsply 0.06, Dentsply TP, Dentsply FM) and pure gutta-percha (control) were analysed using differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA). The transition temperatures were determined and analysed. With the exception of Dentsply 0.04 and Dentsply 0.06, the majority of the products showed thermal behaviour typical of beta-gutta-percha, with two endothermic peaks, exhibiting two crystalline transformations upon heating from ambient temperature to 130°. Upon cooling and reheating, few samples presented two endothermic peaks. It was concluded that heating dental gutta-percha to 130°C causes changes to its chemical structure which permanently alter its physical properties.

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Study of thermal properties of Ga0.5In1.5Se3 by differential scanning calorimetry

Modern Physics Letters B ◽

10.1142/s0217984921504078 ◽

2021 ◽

pp. 2150407

Author(s):

S. I. Ibrahimova

Keyword(s):

Crystal Structure ◽

Differential Scanning Calorimetry ◽

Thermal Properties ◽

Thermal Effects ◽

Room Temperature ◽

Structural Studies ◽

X Ray Diffraction ◽

Hexagonal Symmetry ◽

Scanning Calorimetry ◽

X Ray

The crystal structure and thermal properties of the [Formula: see text] compound have been investigated. Structural studies were performed by X-ray diffraction at room temperature. The crystal structure of this compound was found to correspond to the hexagonal symmetry of the space group P61. Thermal properties were studied using a differential scanning calorimetry (DSC). It was found in the temperature range [Formula: see text] that thermal effects occur at temperatures [Formula: see text] and [Formula: see text]. The thermodynamic parameters of these effects are calculated.

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A Deep Blue Organic Light Emitting Diodes Characteristic of Isomerically-Featured Phosphine Oxides Containing N-Phenyl Benzimidazole

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17830 ◽

2020 ◽

Vol 20 (8) ◽

pp. 4657-4660

Author(s):

Kyeong Hyeon Kim ◽

Jae Hyeok Lee ◽

Dong-Eun Kim ◽

Hoon-Kyu Shin ◽

Burm-Jong Lee

Keyword(s):

Differential Scanning Calorimetry ◽

Thermal Properties ◽

Thermogravimetric Analysis ◽

Light Emitting Diodes ◽

Organic Light Emitting Diodes ◽

Phosphine Oxides ◽

Scanning Calorimetry ◽

Light Emitting ◽

Deep Blue ◽

Organic Light

An isomeric series of phosphine oxides with N-phenyl benzimidazole such as 2-DPPI, 3-DPPI and 4-DPPI were synthesized for organic light emitting diodes (OLED). The thermal properties of DPPI isomers were determined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). OLED devices using DPPI isomers as the emitting material were fabricated, which configuration was ITO/MoOx [30 nm]/NPB [500 nm]/DPPI [300 nm]/Alq3 [200 nm]/Liq[10 nm]/Al [120 nm]. The emitting colors of the devices were respectively a deep-blue (430 nm, 4-DPPI) and greenish-yellows (510–580 nm, 3-DPPI and 530 nm, 2-DPPI). In particular, the emitting color of 4-DPPI device was not changed during the alteration of applied voltages (6.5–11.5 V), and the CIE coordinate was a satisfactory deep-blue (0.161, 0.101).

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Procedures for Breadmaking Quality Assessment of Rye Wholemeal Flour

Foods ◽

10.3390/foods8080331 ◽

2019 ◽

Vol 8 (8) ◽

pp. 331

Author(s):

Sylwia Stępniewska ◽

Waleed H. Hassoon ◽

Anna Szafrańska ◽

Grażyna Cacak-Pietrzak ◽

Dariusz Dziki

Keyword(s):

Protein Content ◽

Dry Mass ◽

Quality Parameters ◽

Water Soluble ◽

Rye Bread ◽

Low Protein ◽

Rye Flour ◽

Flour Properties ◽

Lower Protein

The aim of this study was to evaluate the baking value of rye flours from industrial mills and to indicate which rye flour quality parameters are the most important predictors of wholemeal rye bread quality for commercially milled rye grains. Ten wholemeal rye flours, which were characterized by ash content ranging from 1.43% to 2.42% d.m. (dry mass), were used for the study. The parameters that characterize the flour properties and the baking test were assessed. The study revealed that for the analyzed commercial rye flours, the falling number test and the amylograph properties are insufficient parameters for predicting the quality of wholemeal rye bread. The manufacture of good quality wholemeal bread requires the use of rye flour with superior quality, such as fine granulation, low protein content, low total and insoluble pentosans content, and, in particular, a high percentage of water-soluble pentosans content. Breads with a higher volume were obtained from rye flours that were generally characterized by lower protein content, lower total and insoluble pentosans content, and higher water-soluble pentosans content. Flour granulation and the percentage of water-soluble pentosans content especially, had a significant impact on bread’s hardness of crumb and the hardness of crumb’s increase during bread storage.

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Wheat and flour quality relations in a commercial mill

Czech Journal of Food Sciences ◽

10.17221/6606-cjfs ◽

2013 ◽

Vol 19 (No. 5) ◽

pp. 189-195 ◽

Cited By ~ 3

Author(s):

M. Hrušková ◽

K. Hanzlíková ◽

P. Varáček

Keyword(s):

Protein Content ◽

Quality Parameters ◽

Ash Content ◽

Activity Measurement ◽

Western Region ◽

Falling Number ◽

Bread Making ◽

Gluten Index

The bread-making quality of forty commercial winter wheat samples, grown in the western region of the CzechRepublic, and their flours (white flours with ash content of about 0.5%) prepared in a commercial mill was studied. Standard analytical methods (ash and protein content, wet gluten), amylolytic activity measurement (falling number), rheological investigation (alveograph, gluten index), sedimentation test and laboratory baking test were used for characterization of wheats and flours. In addition NIR method was used to calculate ash, wet gluten, sedimentation value and protein content. Statistically significant correlations were found practically between all tested quality parameters of wheat and corresponding flour samples. However, the strongest correlation (r = 0.69–0.70) significant at 0.01 level exists between specific bread volume and protein and wet gluten content, determined both by standard or by NIR methods. 

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