Maillard Mash, Washback Microbiota & Mixed Fermentations

By the Scottish Section

THURSDAY, 3rd February 2022, 16:00 – 17:30 GMT

Join this free webinar to learn from three PhD students from Heriot-Watt University about the latest whisky production research investigation on flavour, microbiota and washback ketones and brewing mixed culture fermentation.

Presentation 1: Roasted malts for novel flavours in whisky production by Rutele Marciulionyte

Roasted malts are extensively used in brewing industry to enhance beer taste, mouthfeel and colour. The majority of Scotch malt whisky is made using unroasted, lightly kilned malted barley that yields only delicate aromas to the finished product, and the characteristics differentiating whisky of one distillery from another is primarily introduced by varied fermentation, distillation and maturation practices.

With demand increasing for greater product variety, there is a higher interest in the use of specialty malts as a tool for aroma control. Our research group is investigating malt roasting as a new way of introducing flavour volatiles to the spirit through Maillard and caramelisation reactions, and also the implications of such malts on yeast health, alcohol production efficiency and distillate quality.

Presentation 2: The fungi, the ketones, and the washback: The influence of distillery microbiota on whisky flavour by Hannah Proctor

During Scotch malt whisky production, fermentation was traditionally carried out in large wooden vessels known as washbacks. Although wooden washbacks are still widely used today, many distilleries are now opting for stainless steel vessels. When comparing new make and mature spirit produced in both types of vessel, differences in levels of flavour-active methyl ketones and their corresponding ‘green’ and ‘sour’ sensory attributes were observed.

Our research in collaboration with the Nikka Whisky Distilling Co. aims to investigate the origin of these flavours in whisky with a focus on the fungal communities present on wooden washbacks.

Presentation 3: Exploring the potential and control of mixed culture fermentations in brewing by Barnaby Pownall

Whilst most brewery fermentations are carried out using a single strain of either Saccharomyces cerevisiae or S. pastorianus, the participation of wild yeast strains in mixed culture fermentations increases the number of potential outcomes for the brewer. Coupled with conventional brewing strains, mixed culture fermentations result in differences in nutrient consumption and production of aroma-active volatile compounds when compared with monoculture fermentations.

Our research explores the impact that the inclusion of non-conventional yeast strains in the inoculation culture has on fermentation kinetics and yeast metabolism, and whether a mixed culture approach may find specific applications in the fermentation of high gravity wort. This presentation will provide advances on previously given material.

Why you should attend?

• Find out the latest research into novel whisky flavours
• Learn how washback ketones can influence new make spirit
• Discover if mixed culture fermentations can help your brewery

Speakers: 

• Rutele Marciulionyte, PhD Student - Heriot-Watt university

Rutele holds a BSc degree in Medicinal Chemistry from The University of Edinburgh. She’s worked at analytical laboratories for years, but also has copious professional experience in music festivals, beer bars and whisky events. Currently, Rutele is a PhD student at Heriot-Watt University, where she combines her passion for chemistry and Scotch whisky.

• Hannah Proctor, PhD Student - Heriot-Watt university

Hannah obtained a BSc (Hons) in Microbiology from the University of Glasgow before working as a microbiologist at a blue biotechnology start-up based at the European Centre for Marine Biotechnology in Oban. She has since swapped shellfish for whisky and is currently completing a PhD at Heriot-Watt University researching the role of microorganisms in whisky flavour.

• Barnaby Pownall, PhD Student - Heriot-Watt university

Barnaby began his professional association with beer and brewing in 2016, obtaining an MSc in Fermented Beverage Science and Technology at Rovira and Virgili University in Spain. Upon graduation, he started work at Garage Beer Co. in Barcelona, first as cellar brewer and latterly as quality control manager. Since January 2020 he has been pursuing a PhD exploring mixed culture fermentations at Heriot-Watt University.

Hosted by:

• Ken Duncan, Secretary - IBD Scottish Section