Research of hop polyphenols impact on malt hopped wort aroma formation model experiments

Abstract

Currently, a lot of research is being done on the flavoring compounds of hops. However, much less attention has been paid to the aroma formation considering the hop polyphenol different groups by various methods at the wort hopping stage. Therefore, the main goal of the research is an impact of hopping conditions on the polyphenolic compounds, when the hop is extracted variously into both wort and water to better understand extraction conditions, mechanisms, and factors as well as aroma formation considering various groups of polyphenols. As shown the hop variety, boiling time, and treatment type affect the hop polyphenols amount extracted into the wort. Aromatics varied upon a hop variety and wort boiling time accompanying a positive softening effect regarding aroma formated from malt wort compounds comparing to hopped aqueous extracts. The research proved the most noticeable pH (7 and above) impact on aroma formation caused by the polyphenol conversion. As also shown the first time, a temperature and acidic pH doubled the rutin amount, as well as the best extraction of the prenylflavanoid isoxanthohumol, was achieved by boiling at an alkaline medium pH. The results obtained indicate that various hydrophilic amino acids containing in the wort can stabilize polyphenols affecting the quality indicators of beer produced from different grain raw materials.

Migration of Hop Polyphenols in Beer Technology: Model Solution for Various Hopping Methods

“…Полифенолы хмеля, как и другие соединения, отвечают за формирование вкусовых оттенков пива наряду с горькими α-кислотами, их изо-формами и эфирными смолами [2].…”

The Influence of Biomolecule Composition on Colloidal Beer Structure

“…Along with bitter resins, polyphenol hop compounds are extracted, which form a phenol profile responsible for the stability of the colloidal system of beer [ 112 ]. Thus, it was found that amino acids of a hydrophilic nature (arginine, aspartic acid) contained in wort interact with hop catechins [ 113 ] through the decarboxylation of amino acid and detaching of catechin hydroxy groups to form a biogenic catechol amine, which leads to stabilization of hop polyphenols [ 114 ]. This fact makes the process of apoptosis induction in cancer cells a little clearer by inhibiting the activity of tumor necrosis factor α (TNF-α) with the participation of biogenic amine [ 115 ].…”

Влияние Полифенолов Хмеля На Качество Пива

“…Совсем недавно было установлено, что полифенолы хмелепродуктов влияют на образование вкуса и аромата в зависимости от количественного аминокислотного состава сусла, рН среды и времени и стадии внесения хмелепродуктов [13].…”

“…На рисунке 1-2 представлено изменение профиля охмеленного сусла в зависимости от ряда факторов (момента внесения, типа хмеля и способа охмеления) на органолептический профиль [13]. Влияние изменения рН среды также было изучено (рисунок 3) и показало изменение пространственной конфигурации полифенольных соединений в зависимости от кислотности среды [13].…”