Přejít k hlavnímu obsahu

Přihlášení pro studenty

Přihlášení pro zaměstnance

Publikace detail

Influence of Malting on Distribution of Free and Bonded Barley Phenolic Compounds
Autoři: Česlová Lenka | Šilarová Petra | Mazáčová Renáta | Arigo Adriana
Rok: 2016
Druh publikace: ostatní - přednáška nebo poster
Strana od-do: nestránkováno
Tituly:
Jazyk Název Abstrakt Klíčová slova
eng Influence of Malting on Distribution of Free and Bonded Barley Phenolic Compounds Phenolic compounds are presented in barley grain as a free or bonded to the cell wall with proteins or carbohydrates. They are enzymatically liberated from this bond mainly during germination in malting process. On the start of the brewing process, only the soluble phenolics are released during mashing. The content of soluble phenolic compounds is therefore very important factor for the quality of beer, because almost 80% of these compounds in beer come from malt. The phenolic compounds can protect the beer before sensory aging because of their antioxidant properties and also exhibit positive influence on health. Soluble phenolic compounds (mainly free non-conjugated and soluble conjugated compounds to the carbohydrates via ester or ether bond) are extracted from barley and malt to the hydro-organic solvents. Insoluble bonded phenolic compounds are necessary to liberate from ether or ester bond by acidic or alkaline hydrolysis, respectively. In this work, extraction procedure and reversed-phase HPLC/MS separation were optimized to analyze free and bonded phenolic compounds in natural barley and malt. The separation was performed on octadecyl silica gel column packed with fused core particles using gradient elution with acetonitrile and water with 0.3% (v/v) formic acid as a mobile phase. The mass spectrometer in MRM mode was used for the quantitative analysis. The amount of phenolic compounds was determined in individual extracts of barley, which differs in variety and location. Further, the change in distribution of free and bonded phenolic compounds in extracts prepared from barley in the individual malting steps during laboratory micromalting was monitored. phenolic compounds, barely, malt, HPLC/MS