Determination of gushing potential of barley

Sylvie Běláková,Tomáš Foltýn,Natálie Belcredi Březinová,Marek Pernica,Zdeněk Svoboda,Karolína Benešová,Rastislav Boško

doi:10.18832/kp2021.67.548

Abstract

A new control method for the determination of the malting barley susceptibility to gushing was developed. The method is based on the modified Carlsberg test (MCT) after prior stimulation of barley with substances that promote the germination process. Barleys from the harvest of 2020 and malts produced from them were used to develop and verify the method. The selection of barleys was based on the results of gushing potential detected in the produced malts. To optimise and verify the method, the barley variety Sunshine with a high gushing potential of both barley (139±33 g) and malt (144±13 g), and the barley variety Pionier with zero gushing potential of both barley and malt were used. Malt was produced from the Lodestar barley variety with a high content of the mycotoxin deoxynivalenol. Gushing of the malt was 127±10 g. The gushing potential in barley was determined by the MCT method after prior stimulation of germination. For comparison, the gushing potential was also determined by the MCT method without stimulation of germination. It was proved that stimulation of germination is a key process for correct determination of the susceptibility of barley to gushing. The newly developed method was used for the determination of the gushing potential of five barleys from the harvests of 2020 and 2021. Control gushing determination of five malt samples was performed using the MCT method. An agreement between the measured data was found.

Highlights

The brewing and beverage industry still faces a problem of gushing (Christian et al, 2010). This phenomenon negatively affects an image of beer and incurs economic losses to breweries and maltsters (Sarlin et al, 2005)
Samples To optimize the method of gushing prediction in barley, two samples of spring barley varieties (Sunshine and Pionier) and malts produced from them and one sample of spring barley (Lodestar variety), which was malted in the micromalting plant of the Malting Institute in Brno (Research Institute of Brewing and Malting), were used
A sample of barley variety Sun- tion was made based on the assumption that contamishine (A) where the produced malt showed high gush- nated barley would show a high gushing potential ing was selected

Summary

Introduction

The brewing and beverage industry still faces a problem of gushing (Christian et al, 2010). This phenomenon negatively affects an image of beer and incurs economic losses to breweries and maltsters (Sarlin et al, 2005). That means the release of excess pressure above beer causes formation of a very high number of fine bubbles in the entire volume of a beer which ascend very quickly, creating foam. This foam flows out of the bottle or, in severe cases, spurts from the bottle (Gjertsen, 1967). The principle of this relatively complex phenomenon is an immediate release of carbon dioxide after the bottle opening (Shokribousjein et al, 2011)

Objectives

Methods

Results