Abstract
Fungal infection of barley and malt, particularly by strains of the
genus Fusarium, is known to be a direct cause of beer gushing. We have shown
previously that small fungal proteins, hydrophobins, isolated from strains of
the genera Fusarium, Nigrospora and Trichoderma act as gushing factors in
beer. A hydrophobin concentration as low as 0.003 ppm was sufficient to induce
gushing. The gushing-inducing abilities of the isolated hydrophobins varied
probably due to their structural differences. The hydrophobins did not affect
beer foam stability. A correlation was observed between the hydrophobin level
analyzed by the hydrophobin ELISA developed and the gushing potential of malt.
The risk of gushing was found to increase with hydrophobin concentrations
above 250 µg/g malt. The levels of hydrophobin and the Fusarium mycotoxin
deoxynivalenol (DON) in malts were not correlated which indicated that the
formation of those two fungal metabolites may not be linked. Furthermore, we
did not observe a correlation between the DON content and the gushing
potential of the malt studied. Our observations suggest that the accuracy of
predicting gushing could be improved by measuring the amount of the actual
gushing factors, hydrophobins, in barley or malt.
Original language | English |
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Pages (from-to) | 105-111 |
Journal | Journal of the Institute of Brewing |
Volume | 111 |
Issue number | 2 |
DOIs | |
Publication status | Published - 2005 |
MoE publication type | A1 Journal article-refereed |
Keywords
- beer gushing
- ELISA
- hydrophobins
- prediction of gushing risk in malt