			Home About us Contact

Dough Rheological Properties (dough + rheological_property)

Distribution by Scientific Domains

Chemistry	100%

Selected Abstracts

Quantification of monomeric and polymeric wheat proteins and the relationship of protein fractions to wheat quality,

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 10 2003
Jerry Suchy
Abstract Wheat protein composition is important for understanding the biochemical basis of wheat quality. The objective of this study was to design a simple protein fractionation protocol with low cross-contamination and to show that these protein fractions were associated with wheat quality. The protocol consists of three sequential extractions from 100 mg of flour with 7.5% propan-1-ol and 0.3 M sodium iodide (monomeric-rich protein), 50% propan-1-ol (soluble glutenin-rich protein) and 40% propan-1-ol and 0.2% dithiothreitol (insoluble glutenin-rich protein). Nitrogen content of protein solubility groups was determined from dry residues using an automated combustion nitrogen analyser. About 90% of the total protein in the flour was solubilised. Cross-contamination of protein fractions was evaluated by SDS-PAGE, SE-HPLC and RP-HPLC. Variation in nitrogen content of the protein solubility fractions was lowest for monomeric-rich protein (<2%) and insoluble glutenin-rich protein (<4%). Three wheats with similar high-molecular-weight (HMW) glutenin subunit composition, Alpha 16, Glenlea and Roblin, varied significantly (P , 0.05) in the proportion of monomeric-rich and insoluble glutenin-rich protein in the flour. Dough rheological properties were directly related to the proportion of insoluble glutenin-rich protein and inversely related to the proportion of monomeric-rich protein. The protocol was validated using an expanded set of 11 wheats which also showed that inter-cultivar differences in the proportion of monomeric-rich, insoluble glutenin-rich protein and glutenin-to-gliadin ratio in the flour governed dough rheological properties such as mixograph, farinograph and microextension tests. The protocol has merit for quality screening in wheat-breeding programmes when the sample size is too small or when time constraints limit the ability to perform traditional rheological tests. For the Department of Agriculture and Agri-Food, Government of Canada, Copyright © Minister of Public Works and Government Services Canada 2003. Published for SCI by John Wiley & Sons, Ltd. [source]

Wheat dough rheology and bread quality effected by Lactobacillus brevis preferment, dry sourdough and lactic acid addition

INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 7 2010
Daliborka Koceva Komleni
Summary The influence of chemical and biological acidification on dough rheological properties and bread quality has been investigated. Two different flour types were used. Dough was chemically acidified with lactic acid. Two types of biologically acidified dough were prepared: dough with dry sourdough and with a Lactobacillus brevis preferment. Wheat dough rheological properties were investigated using the Farinograph, Extensograph and Amylograph. The baking response was also determined using standard baking tests. Addition of acidifiers resulted in firmer doughs with less stability, decreased extensibility and decreased gelatinisation maximum. The biological acidifiers increased the bread specific volume. Lactic acid addition had no influence on bread specific volume. In general, biological and chemical acidification decreased bread hardness. The addition of dry sourdough significantly decreased the lightness and increased the yellowness and redness of the bread crumb. The crust chroma, hue angle and brownness index were significantly changed by addition of acidifiers. [source]

Statistical evaluation of different technological and rheological tests of Polish wheat varieties for bread volume prediction

INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 1 2004
Iwona Konopka
Summary Forty-two Polish wheat flour were used to establish correlation coefficients between protein content, Zeleny test, falling number value, amylograph viscosity, farinograph water absorption, bread volume and rheological properties of dough, as shown by use of a extrusion chamber and alveograph. The equations expressing the changes of bread volume and flour water absorption as a function of significantly correlated parameters were calculated. The correlations and their significance depended on wheat quality and the alveographic parameters were significantly correlated with the dough extrusion parameters. The dough extrusion parameters were significantly correlated only with the water absorption of soft wheats. The dough rheological tests were correlated to a greater extent with the values of the Zeleny test than to the protein content. The prediction of the bread volume as a function of flour quality parameters and dough rheological properties was best done by grouping wheat varieties into specific qualitative classes. [source]

Effect of ,-amylases on dough properties during Turkish hearth bread production

INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 2 2003
smail S. Do
Summary The effect of ,-amylases from cereal and fungal sources on dough rheological properties was studied. Increasing the enzyme addition level to 160 SKB units (c. 1.1%, fwb) decreased dough stability and increased mixing tolerance indexes. Gas production rates with cereal ,-amylase were higher than that with fungal ,-amylases, indicating more activity during fermentation. A higher adsorption rate occurred with cereal ,-amylase. Dough stability is very important for Turkish hearth bread production, as it is for other hearth breads. Spread ratio tests on fermented doughs showed significant changes in dough rheological properties as a function of ,-amylases. The spread test is a reliable tool for observing rheological changes during fermentation. As a guide, the dough spread ratio should not be more than 2 for desirable bread. [source]