scholarly journals Applicability of Mixolab test with local wheat flours

2015 ◽  
Vol 4 (1) ◽  
Author(s):  
Daniel Vazquez ◽  
María C. Veira

Several types of equipment have been used to predict dough behaviour during breadmaking. The complexity of requirements means that no device is able to predict all the properties, and therefore, new tests are released continuously. The Chopin Mixolab mixes the dough at different temperatures, allowing the study of dough mixing properties, weakening, gelatinization, gel stability and retrogradation in one test. The objective of this work was to study the suitability of the Mixolab to predict rheological properties and breadmaking quality of local wheats. Flour was obtained from 29 wheat samples  from different genotypes and environments. The correlation of results from traditional analyses  (test weight, protein content, sedimentation volume, wet gluten, Falling Number, Alveograph and Farinograph)  with Mixolab parameters was studied. The properties of two different bread types were compared with all these parameters. Stability and water absorption values from the Farinograph were highly correlated with the respective Mixolab parameters. It was concluded that wheat samples could be sorted by mixing properties in similar order independently of which method was used. Beyond that, gluten strength estimators obtained from these three rheological methods and the sedimentation volume test were highly correlated. Whilst the correlation of Mixolab parameters with pan loaf volume was not as high as traditional ones, Mixolab developing time, stability and C5 were the best correlated with the most important hearth bread characteristics. Studies performed by other researchers, using wheats from diverse origins, found different results. The need for empirical rheology evaluation with local wheat samples was proved.

2003 ◽  
Vol 33 (1) ◽  
pp. 34-37 ◽  
Author(s):  
L.M. Keswet ◽  
J.A. Ayo ◽  
C.B. Bello

2005 ◽  
Vol 11 (6) ◽  
pp. 471-476 ◽  
Author(s):  
S. H. Park ◽  
N. Morita

Dough physical properties and baking quality of wheat flour substituted by 10% with non germinated quinoa flour (control), 24-h, 48-h and 72-h germinated quinoa flours were studied. The stability time and valorimeter value of the control and 24-h germinated quinoa flour substituted wheat flours were significantly longer and higher than those of 48-h and 72-h samples. The 10% substitution of germinated quinoa flour for wheat flour made distinctly harder dough than that of the control. The low amount of total and inner gas generations was observed for the 48-h and 72-h samples, as compared with those of the control and 24-h germinated quinoa samples. SEM observations showed that the gluten matrix of the control and 24-h germinated quinoa flour substituted wheat dough seemed to be more extended and more dispersed than those of 48-h and 72-h samples. The loaf volume of bread made from 24-h germinated quinoa flour substitution for wheat flour was the largest among the germinated samples; however, no significant differences were observed between the control and 24-h samples.


1982 ◽  
Vol 62 (3) ◽  
pp. 545-553 ◽  
Author(s):  
K. R. PRESTON ◽  
P. R. MARCH ◽  
K. H. TIPPLES

The ability of the sodium dodecyl sulfate (SDS) sedimentation test of Axford et al. (1978) to predict quality characteristics of Canadian bread wheats has been assessed. With appropriate modifications, the test had sufficient "inherent" sensitivity to differentiate Canadian bread wheat lines, obtained from three years of Co-op tests, on the basis of baking quality and physical dough strength. However, the correlation coefficients between SDS-sedimentation volume and the quality parameters tested were highly dependent on environment. Correlation coefficients between SDS-sedimentation volume and Remix loaf volume were strongly affected by protein content with sample sets from the same environment. Sample sets with the lowest average protein contents gave the highest correlations. With combined samples from different environments with protein contents of less than 13.0%, a high correlation coefficient (r = 0.78**) was obtained between SDS-sedimentation volume and Remix loaf volume, whereas with samples of over 14.0% protein the correlation coefficient was insignificant. With sample sets from the same environment, SDS-sedimentation volume was generally highly correlated to farinograph dough development time and extensigraph area.


AGROFOR ◽  
2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Desimir KNEŽEVIĆ ◽  
Aleksandra Novoselskaya DRAGOVIČ ◽  
Aleksandr KUDRYAVCEV ◽  
Danijela KONDIĆ ◽  
Gordana BRANKOVIĆ ◽  
...  

High molecular weight glutenin subunits (HMW-GS) proteins deposited inendosperm of wheat seed which have significant impact on bread quality. TheHMW-GS encoded by genes located at the long arm of chromosomes 1A, 1B, 1D.The aim of this work was study allele polymorphysms at Glu-A1, Glu-B1 and Glu-D1 locus and loaf volume, grain protein content, sedimentation volume of eightwheat genotypes (G-3130, G-35183, G-3501, G3512, G-3574, G-3027, G-3075, G-3097) harvested in two years with various weather condition. For each genotypes,flour used for extraction of glutenin which separated by method of electrophoresison SDS gel (11.8%). Electrophoregrams used for determining Glu-1 alleles.Technological quality parameters analyzed by standard laboratory methods. Thethree alleles alleles (a, b, c) at the Glu-A1, three alleles (b, c, d) at the Glu-B1 and 2alleles (a, d) at the Glu-D1 were identified. The highest protein sedimentationvolume had wheat genotype G-3075 in the both years (54.0ml; 58.0ml) while thelowest sedimentation volume had G-3512 (34.0ml; 36.0ml). Grain protein content(GPC) was the highest in G-3075 in both years (14.20%; 15.40%) while the lowestGPC had G-3097 (11.60%) in first and G-3512 (12.60%) in the second year. Loafvolume was the highest in G-3075 in both year (520ml; 540ml) while the lowestwas in G-3512 (400ml) in both years of experiment. The estimated quality traitsvaried depending on genotype and year. The better quality, in average, had thewheat genotypes which carried Glu-D1d allele.


2017 ◽  
Vol 908 ◽  
pp. 45-50
Author(s):  
Dušan Dolák ◽  
Karel Dvořák ◽  
Jaroslav Bureš

Limestone as a natural rock tends to have various parameters. Variation in parameters, as well as firing temperature have significant impact on key properties of quicklime. Sedimentation volume and reactivity determine quality of quicklime in building industry. This paper is focused on monitoring the reactivity and sedimentation volume of quicklime prepared from various types of limestone at different temperatures. Selection of limestones with high purity collected from various quarries around the world were characterized by porosity, chemical and petrographic composition. To create quicklime, these samples were fired at 4 different temperatures. Reactivity measurements were made on quicklime with specific particle size. Sedimentation volume of hydrated slurry was determined. Obtained results suggest that there is tendency for slower reactivity and smaller sedimentation volume with increased firing temperature.


2017 ◽  
Vol 76 ◽  
pp. 236-242 ◽  
Author(s):  
Huayin Pu ◽  
Jianling Wei ◽  
Le Wang ◽  
Junrong Huang ◽  
Xuefeng Chen ◽  
...  

Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 642
Author(s):  
Yuliia Kochiieru ◽  
Audronė Mankevičienė ◽  
Jurgita Cesevičienė ◽  
Roma Semaškienė ◽  
Jūratė Ramanauskienė ◽  
...  

In this work, we studied the impact of harvesting time on Fusarium mycotoxin occurrence in spring wheat and the effect of mycotoxin contamination on the quality of these grains. The spring wheat grains (Triticum aestivum L.) were collected in 2016–2018 when the crop had reached full maturity, 10 ± 2 days and 17 ± 3 days after full maturity. The grain samples were analyzed for Fusarium infection and co-contamination with mycotoxins deoxynivalenol (DON), zearalenone (ZEA), and T-2 toxin (T-2), as well as the quality of the wheat grains (mass per hectolitre, contents of protein, starch, ash and fat, particle size index (PSI), falling number, sedimentation, wet gluten content, and gluten index). The occurrence of Fusarium spp. fungi and the mycotoxins produced by them in the grains was mostly influenced by the harvesting time and meteorological conditions. The correlations between Fusarium species and the mycotoxins produced by them in the grains of spring wheat showed F. graminearum to be a dominant species, and as a result, higher concentrations of DON and ZEA were determined. The co-occurrence of all the three mycotoxins analyzed (deoxynivalenol, zearalenone, and T-2 toxin) was identified in wheat. In rainy years, a delay in harvesting resulted in diminished grain quality of spring wheat, as indicated by grain mass per hectolitre and falling number. Negative correlations were found in highly contaminated grains between mycotoxins (DON, ZEA, and T-2) and falling number and grain mass per hectolitre values.


2011 ◽  
Vol 78 (4) ◽  
pp. 385-390 ◽  
Author(s):  
Priscilla A Melville ◽  
Nilson R Benites ◽  
Monica Ruz-Peres ◽  
Eugenio Yokoya

The presence of yeasts in milk may cause physical and chemical changes limiting the durability and compromising the quality of the product. Moreover, milk and dairy products contaminated by yeasts may be a potential means of transmission of these microorganisms to man and animals causing several kinds of infections. This study aimed to determine whether different species of yeasts isolated from bovine raw milk had the ability to develop at 37°C and/or under refrigeration temperature. Proteinase and phospholipase activities resulting from these yeasts were also monitored at different temperatures. Five genera of yeasts (Aureobasidium sp., Candida spp., Geotrichum spp., Trichosporon spp. and Rhodotorula spp.) isolated from bovine raw milk samples were evaluated. All strains showed one or a combination of characteristics: growth at 37°C (99·09% of the strains), psychrotrophic behaviour (50·9%), proteinase production (16·81% of the strains at 37°C and 4·09% under refrigeration) and phospholipase production (36·36% of the isolates at 37°C and 10·9% under refrigeration), and all these factors may compromise the quality of the product. Proteinase production was similar for strains incubated at 37°C (16·81% of the isolates) and room temperature (17·27%) but there was less amount of phospholipase-producing strains at room temperature (15·45% of the isolates were positive) when compared with incubation at 37°C (36·36%). Enzymes production at 37°C by yeasts isolated from milk confirmed their pathogenic potential. The refrigeration temperature was found to be most efficient to inhibit enzymes production and consequently ensure better quality of milk. The viability of yeasts and the activity of their enzymes at different temperatures are worrying because this can compromise the quality of dairy products at all stages of production and/or storage, and represent a risk to the consumer.


Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 478
Author(s):  
Stefania Toscano ◽  
Valeria Rizzo ◽  
Fabio Licciardello ◽  
Daniela Romano ◽  
Giuseppe Muratore

The aim of the study was to assess, through a comparative shelf-life test, the suitability of two packaging materials, namely macro-perforated polypropylene (PP MA) and micro-perforated coextruded polypropylene (PP C), for the quality preservation of green asparagus (Asparagus officinalis L. ‘Vegalim’). Quality of spears was evaluated during 30 days at refrigerated storage by monitoring chemical, physical, and enzymatic parameters as well as sensory descriptors. PP C kept headspace composition close to suggested values for fresh green asparagus. Total color difference increased during the storage and it was highly correlated with chlorophyll-a and carotenoids, however, sensory color perception did not change significantly until 22 days of storage. PP C maintained ascorbic acid concentrations close to the initial levels, limited total phenolic compound loss to 24% (45% in PP MA), determined an increase of 72% in fiber content and small changes in lignin value; enzymatic changes were significantly inhibited. Significant sensorial differences were detected after 22 days of storage, with PP C performing better than PP MA. PP C film was confirmed as the best choice, limiting weight loss and maintaining a fresh-like appearance during 30 days of storage, thus allowing an extension in postharvest life.


2012 ◽  
Vol 562-564 ◽  
pp. 188-191
Author(s):  
Keh Moh Lin ◽  
Yang Hsien Lee ◽  
Wen Yeong Huang ◽  
Po Chun Hsu ◽  
Chin Yang Huang ◽  
...  

To find out the important factors which decisively affect the soldering quality of photovoltaic modules, solar cells were soldered under different conditions (different temperatures, PbSn vs. SnAgCu solder, manual vs. semi-automatic). Experimental results show that the soldering quality of PbSn under 350°C in the semi-automatic soldering process was quite stable while the soldering quality of lead-free solder was generally unacceptable in the manual or semi-automatic process under different temperatures. This result indicates that the soldering process with lead-free solder still needs to be further improved. It was also found that most cracks were formed on the interface between the solder and the silver paste and then expanded outwards.


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