scholarly journals Ohmic Baking of Gluten-Free Bread: Role of Starch and Flour on Batter Properties

2021 ◽  
Vol 11 (14) ◽  
pp. 6567
Author(s):  
Elok Waziiroh ◽  
Denisse Bender ◽  
Anisa Saric ◽  
Henry Jaeger ◽  
Regine Schoenlechner

The viscosity of gluten-free (GF) batter significantly influences GF bread quality. This study attempts to understand how the rheological properties of GF batter are affected by the type of starch and the amount of water and how they influence GF bread properties when baked with two methods (conventional oven, ohmic heating). For this purpose, the physical and chemical properties of different starches (corn, wheat, potato, cassava) and GF flours (rice, buckwheat) were evaluated. Rheological behavior of GF batter was not only influenced by the starch:water ratio, but also greatly by the starch source and structure, which influenced its physical properties (e.g., water holding capacity, swelling power, solubility, starch damage, and pasting properties). All batters consistently exhibited shear-thinning and dominant viscous behavior. Between viscosity and ohmic-heated bread properties, a non-linear relationship was observed. Two categories of required water content or viscosity ranges were defined for estimating final GF bread properties: low water content with a viscosity range of 47.12–56.20 Pa·s for B-type starches, and medium water content with a low to medium viscosity range of 2.29–15.86 Pa·s for A-type starches. This finding could be useful for further research to design GF batter viscosities for tailored bread quality.

2004 ◽  
Vol 49 (3) ◽  
pp. 165-172 ◽  
Author(s):  
M. Yazgan ◽  
A. Tanik

The study covers the investigation of pesticides in terms of consumption, toxicological classification and various intrinsic physical and chemical properties like DT50, KOC, GUS, solubility that describe the important mechanisms prevailing in soil, namely persistence and mobility. These mechanisms help to estimate the transportation pathways of pesticides on soil till they reach the receiving water after being applied on land. Classification is done in three groups, those likely to appear in surface flow, those that appear in groundwater and those that present transient conditions. Such an approach that also takes into account toxicological levels and annual consumption values of pesticides will act as a tool to prepare the priority list of pesticides that need special care during their transportation. The fate of pesticides is a difficult task to solve, however, such a methodology, puts forth a rough estimate on their behavior in spite of uncertainties in many of the parameters describing mechanisms like persistence and mobility. The agricultural areas of two watersheds of Istanbul are selected as target areas to describe the approach, which is also checked with another approach estimating pesticide pollution potential that considers various other properties of pesticides. Almost similar findings are depicted with 85% proximity. The methodology presented in the paper illustrates and emphasizes the significant role of pesticide properties in determining their fate in soil after being applied.


1973 ◽  
Vol 51 (21) ◽  
pp. 3605-3619 ◽  
Author(s):  
C. Willis ◽  
R. A. Back

Preparation of di-imide by passing hydrazine vapor through a microwave discharge yields mixtures with NH3 containing typically about 15% N2H2, estimated from the gases evolved on decomposition. The behavior of the mixture (which melts at −65 °C) on warming from −196 to −30 °C suggests a strong interaction between the components. Measurements of magnetic susceptibility and e.p.r. experiments showed that N2H2 is not strongly paramagnetic, which with other observations points to a singlet rather than a triplet ground-state.Di-imide can be vaporized efficiently, together with NH3, by rapid warming, and the vapor is surprisingly long-lived, with a typical half-life of several minutes at room temperature. The near-u.v. (3200–4400 Å) absorption spectrum of the vapor was photographed; it shows well-defined but diffuse bands, with εmax = 6(± 3) at 3450 Å.Di-imide decomposes at room temperature in two ways:[Formula: see text][Formula: see text]Formation of NH3 was not observed but cannot be ruled out. The decomposition of the vapor is complicated by a sizeable and variable decomposition that occurs rapidly during the vaporization. The stoichiometry of this and the vapor-phase decomposition depends on total pressure and di-imide concentration. The kinetics of the decomposition of the vapor were studied from 22 to 200 °C by following the disappearance of N2H2 by absorption of light at 3450 Å, or the formation of N2H4 by absorption at 2400 Å, and by mass spectrometry. The kinetics are complex and can be either first- or second-order, or mixed, depending on surface conditions. The effect of olefin additives on the decomposition was studied, and is also complex.Mechanisms for the decomposition are discussed, including the possible role of trans-cis isomerization. The relatively long lifetime found for di-imide in the gas phase suggests that it may be an important intermediate in many reactions of hydronitrogen systems.


Author(s):  
John Evans

The chemical properties of the volatile elements in groups 15 to 18 are outlined, showing how the the periodicicty of the properties of the elements shapes their chemistry. The manufacture of hydrogen and chlorine is described, showing how mercury-free methods have been developed for the latter. The effect of the formation of atmospheric CO2 on atmospheric oxygen content is explained in terms of dissolution in the oceans. Remediation of the exhaust gases from internal combustion engines by catalysts to remove CO2, NOx and carbonaceous particulates is explained. Options for carbon capture and storage by physical and chemical processes are evaluated, and examples provided of these processes in operation. Exploitation of the atmosphere for energy capture using wind turbines has been aided by the development of high performance magnets. The basis of these magnets and the role of rare earth elements is explained.


2020 ◽  
Vol 166 ◽  
pp. 06007
Author(s):  
Myroslav Sanytsky ◽  
Tetiana Kropyvnytska ◽  
Stanislav Fic ◽  
Hanna Ivashchyshyn

Sustainable development depends on a consistency of interests, social, ecological and economic, and that the interests are evaluated in a balanced manner. In order to reduce CO2 emissions, the conception of decreasing clinker factor and increasing the role of supplementary cementitious materials (SCMs) in the cementitious materials has high economical and environmental efficiency. The performance of clinkerefficient blended cements with supplementary cementitious materials were examined. The influence of superfine zeolite with increased surface energy on the physical and chemical properties of low-carbon blended cements is shown. Increasing the dispersion of cementitious materials contributes to the growth of their strength activity index due to compaction of cement matrix and pozzolanic reactions in unclincker part. In consequence of the early structure formation and the directed formation of the microstructure of the cement matrix is solving the problem of obtaining clinker-efficient concretes. Shown that low-carbon blended cements with high volume of SCMs are suitable, in principle, for producing structural concretes.


2020 ◽  
Vol 21 (8) ◽  
Author(s):  
Muhammad Fajri ◽  
Pratiwi PRATIWI ◽  
Yosep Ruslim

Abstract. Fajri M, Pratiwi, Ruslim Y. 2020. The characteristics of Shorea macrophylla’s habitat in Tane’ Olen, Malinau District, North Kalimantan Province, Indonesia. Biodiversitas 21: 3454-3462.  Shorea macrophylla is a tree species in Tane' Olen forest area. This study analyzed the soil’s physical and chemical properties, topography, and microclimate of S. macrophylla’s habitat. A purposive method was used to select a sampling plot and to place the subplots. Soil was analyzed to determine the physical properties, i.e., texture, bulk density, porosity, and water content, and the chemical properties, i.e., pH, CEC, total N, organic C, C/N ratio, P, K , and Al saturation. Importance value index was determined for each tree species to know the species composition in the study site. Only the dominant species were presented. The soil at the study site had bulk density of 0.60-1.31 gram cm³-1, porosity 50.60%-77.35%, water content 34.88%-95.37%, and soil texture sandy clay. The chemical properties of the soil were as follows: pH was 3.6-4.8, N 0.05%-0.19%, organic C 1.40%-3.65%, P 0.41-1.22 mg 100 gr-1, K 58.68-232.55 mg 100 gr-1, and Cation Exchange Capacity (CEC) 5.35-10.81 meg 100gr -1. Slope ranged between 0 and 25%. The microclimate characteristics were as follows: temperature was 24-26.5°C, relative humidity 76-87%, and light intensity 145-750 Lm. Trees species with an IVI ≥ 10% were S. macrophylla, Madhuca spectabilis, Myristica villosa Warb, Scorodocarpus borneensis, Eugenia spp., Palaquium spp., Macaranga triloba, Syzygium inophyllum and Shorea sp. Positive associations were observed between S. macropylla and S. borneensis, Eugenia spp., Palaquium spp.. and M. triloba, and negative associations were observed between S. macropylla and M. spectabilis, M. villosa Warb, S. inophyllum, and Shorea sp. S. macrophylla grows on riversides with flat and gentle topography, acidic soil, and lower fertility but with suitable microclimate. This species can be recommended to be planted in degraded tropical forest areas but the microclimate and soil properties should be taken into account.


2012 ◽  
Vol 578 ◽  
pp. 183-186
Author(s):  
Xiao Chun Cao ◽  
Yi Qin ◽  
Yan Na Zhao ◽  
Kun Ke

Using the preliminary research of the polymer properties, the different between the physical and chemical properties of new polymer-clays nanometer composites and clay have been studied. Different polymers are used to evaluate experiment. Based on a large number of lab experiments, the changes of rheological property and API filtration property of polymer-clay drilling fluids nanometer composites are studied. The results show that clay particles could become smaller and the composites drilling fluid have the role of controlling loss and enhancing cake quality. The prepared composites could be used to solve the technical problems in drilling fluid.


2015 ◽  
Vol 17 (26) ◽  
pp. 16733-16743 ◽  
Author(s):  
Lipeng Zhang ◽  
Quan Xu ◽  
Jianbing Niu ◽  
Zhenhai Xia

Defects are common but important in graphene, which could significantly tailor the electronic structures and physical and chemical properties.


2006 ◽  
Vol 6 (7) ◽  
pp. 2017-2038 ◽  
Author(s):  
S. Fuzzi ◽  
M. O. Andreae ◽  
B. J. Huebert ◽  
M. Kulmala ◽  
T. C. Bond ◽  
...  

Abstract. In spite of impressive advances in recent years, our present understanding of organic aerosol (OA) composition, physical and chemical properties, sources and transformation characteristics is still rather limited, and their environmental effects remain highly uncertain. This paper discusses and prioritizes issues related to organic aerosols and their effects on atmospheric processes and climate, providing a basis for future activities in the field. Four main topical areas are addressed: i) sources of OA; ii) formation transformation and removal of OA; iii) physical, chemical and mixing state of OA; iv) atmospheric modelling of OA. Key questions and research priorities regarding these four areas are synthesized in this paper, and outstanding issues for future research are presented for each topical area. In addition, an effort is made to formulate a basic set of consistent and universally applicable terms and definitions for coherent description of atmospheric OA across different scales and disciplines.


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