Tag Archives: alpha amylase

1234–1248 M. Kostyuchenko, V. Martirosyan, M. Nosova, G. Dremucheva, E. Nevskaya and O. Savkina
Effects of α-amylase, endo-xylanase and exoprotease combination on dough properties and bread quality
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Effects of α-amylase, endo-xylanase and exoprotease combination on dough properties and bread quality

M. Kostyuchenko¹*, V. Martirosyan¹, M. Nosova¹, G. Dremucheva¹, E. Nevskaya¹ and O. Savkina²

¹Scientific Research Institute for the Baking Industry, Bolshaya Cherkizovskaya Street 26A, RU107553 Moscow, Russia
²St.Petersburg branch Scientific Research Institute for the Baking Industry, Podbelskogo highway 7, RU196608, St. Petersburg, Pushkin, Russian Federation
*Correspondence: kostyuchenkomn@yandex.ru

Abstract:

The enzymes composition is an actual alternative to chemicals to improve functional properties of flours and to generate changes in the structure of the dough and bread quality. The objective of this study was to analyze the individual and synergistic effects of enzymes preparation (α-amylase, endo-xylanase and exoprotease), newly produced in Russia, on dough properties and bread quality made from wheat flour with different amylolytic activity. Reofermentometric results revealed decreases in gas-forming capacity of dough by 10.0–13.9% when single α-amylase preparates were used. The α-amylase addition had significant effect on gas retention coefficient in flour possessed low amylolytic activity. The effect of endo-xylanase and exoprotease on hydration and amount of wheat gluten was established. The fractional composition of gluten proteins in the dough made with combination of endo-xylanase and exoprotease was established using Lowry method immediately after kneading and after fermentation. It was found that mainly water-soluble, alcohol-soluble and alkaline-soluble proteins were undergone by transformation. The bread with enzymes had a higher specific volume, porosity and aldehyde content and lower shape stability indicator than the control bread made without enzymes. Bread with enzymes was characterized by tenderer and not crumbly crumb with developed thin-walled uniform porosity compared to the control. The crusts were more brightly colored. The combined usage of α-amylase and endo-xylanase and exoprotease retarded bread staling during 5-day storage period. New enzyme composition may be a potentially strong candidate for future applications in the bread-making industry.

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1591–1598 V. Dubrovskis, I. Plume and I. Straume
The production of methane from the straw pellets with addition of enzymes
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The production of methane from the straw pellets with addition of enzymes

V. Dubrovskis*, I. Plume and I. Straume

Latvia University of Life Sciences and Technologies, Faculty of Engineering, Institute of Energetics, Cakstes blvd. 5, LV3001, Jelgava, Latvia
*Correspondence: vilisd@inbox.lv

Abstract:

Biogas production requires much cheaper raw materials. The use of straw, as not always the full use of agricultural residues, increases the methane yield in pelletised form compared to non-pelletised straw. Lack is the high ratio of carbon to nitrogen content of straw, which leads to a slow and incomplete breakdown of the matter, and less producing substances from which bacteria produce methane.Variety of additives can be used to improve anaerobic digestion process. This article shows the results of the study, where the enzymes alpha amylase and xylanase and catalysts Metaferm and Melafen mixture are used for the digestion process echancement. Investigation was provided in 16 bioreactors operated in batch mode at 38 °C. Additives were filled into 14 bioreactors and only inoculum were filled into two bioreactors for control. The yield of biogas from straw pellets without additives was 0.655 L g-1DOM and methane 0.301 L g-1DOM after 34 days of anaerobic digestion. The yield of biogas from straw pellets with added alpha amylase was 0.652 L g-1DOM and methane 0.318 L g-1DOM. The yield of biogas from straw pellets with added xylanase was 0.689 L g-1DOM and methane 0.347 L g-1DOM. The yield of biogas from straw pellets with added Metaferm and Melafen mixture was 0.638 L g-1DOM and methane 0.254 L g-1DOM. The study demonstrates that the adding of enzymes increases the production of methane.

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