Subventions et des contributions :

Subvention ou bourse octroyée s'appliquant à plus d'un exercice financier (2017-2018 à 2018-2019).

Brewing is an important industry for the Canadian economy, with small batch craft breweries in particular arex000D
growing rapidly within this sector. Beer is brewed with malted barley, and thus contains many barley-derivedx000D
plant chemicals. Of primary importance among these are the tannins, a mixture of oligomeric and polymericx000D
polyphenols which impact both beer flavour and stability. Tannins can interact with proteins and many otherx000D
biomolecules, and are also known for their positive effects on human health. Under some conditions, tanninsx000D
precipitate proteins and can cause the generation of 'cold haze' in beer. This is a major concern to brewers as itx000D
leads consumers to question the quality of the product. Cold haze can be removed prior to bottling usingx000D
chemical methods or filtration, but for the craft beer industry, alternative approaches are preferred. Therefore, ax000D
long-term goal of malsters and brewers is precise control of barley tannin within malt. Our previous workx000D
indicated that significant changes occur in tannins during the kilning step of malt production: the concentrationx000D
of the water-soluble tannin fraction increases steeply, while other tannin fractions decrease or remain the same.x000D
These changes are likely to be important to the tannin content of beer; to date, nothing is known about thex000D
nature of the water-soluble tannins, for example, if they are composed of larger or smaller oligomeric tannins.x000D
The proposed research will therefore focus on the chemical analysis of the soluble tannin fractions. This will bex000D
done at key stages of the malting process in order to understand tannin dynamics, and also with specialty maltsx000D
kilned under different conditions. Non-tannin components, and in particular phenolic acids, will also bex000D
measured. We will make use of our recently purchased analytical system, a ultra-high pressure liquidx000D
chromatography (UHPLC) system, that will allow us to simultaneously measure compounds by UV absorptionx000D
and mass spectrometry. Ultimately, we aim to determine if the release of water-soluble tannins is mediated byx000D
enzymatic processes, and if these can be manipulated during malting in order to control tannin content of malt.x000D
This would help control cold haze formation, and represent a major advance for craft brewers.