Unmalted cereal ingredients have been used in brewing for hundreds, if not thousands, of years,
and there is, according to Carl Heron of Crisp Malt, a renewed interest in them. This follows decades
of relative indifference among smaller brewers.
“This has, perhaps, been a reaction to the way international players have set their store by inclusions of maize or rice at the rate of over 20%,” he said. “However, brewers in the craft sector are increasingly adventurous. They’re
experimenting extensively with the rich range of malts, but also visiting some of the excellent un-malted cereals on offer.”
Torrefied and micronised wheat, barley, oats, rye, maize and rice all offer the opportunity to play tunes on the flavour notes of beer. They have an impact on colour, head retention, body, smoothness and mouthfeel, and can therefore offer significant help in orchestrating the overall characters of beers.
Clearly, brewers can’t use raw grains. In the past, those that weren’t malted might be passed through a stream of hot sand by grain merchants or had to be put through a cereal mash by brewers (using up precious space in the mash tun). The processes of torrefication and micronisation have provided much more satisfactory answers. They involve rapid cooking of cereals at high temperatures to gelatinise the starchy endosperm.
Torrefication, rather like the sand-based methods of the past, involves passing the grains through a fluidised bed of very hot air at 750 to 780ºF. The cell walls of the grains are disrupted. The grains expand, their density changes, they’re aspirated to remove dust and chaff, then sized and cooled in the ambient air.
Micronisation involves using infrared waves to rapidly heat grains until they ‘pop’. The molecules within the grains vibrate and the molecular friction causes the fast increase in temperature and rise in water vapour pressure. Once the cellular structure has been disrupted, the starch gelatinises.
Torrefied whole or crushed wheat
Torrefied wheat improves head retention, especially in wheat beers. It’s great for use as a nitrogen diluent as it adds very little soluble nitrogen to wort. It also adds subtle depth of flavour and body.
Torrefied flaked barley
Torrefied flaked barley has similar benefits to torrefied wheat, but with a stronger and slightly harsher flavour.
Micronised flaked maize
Micronized flaked maize adds up to 20% of grist to the tun with normal malt, and even more with high diastatic power malt. On top of this, it improves body and mouthfeel, and is gluten and nitrogen free, allowing it to be used as a diluent in coeliac-friendly beers.
Micronised flaked rice
Micronized flaked rice also adds grist to the tun, and adds a greater perception of refreshment. It also accentuates hop aromas, without adding taste.
Micronised flaked oats
Micronized flaked oats improve mouthfeel and increase body, but also impart a smoothness and a pleasant oaty flavour on the beer.
Both torrefication and micronisation can be applied to many cereals, including barley, wheat, rice, maize, oats, and rye, creating grains ready to be used for brewing, providing their own benefits. With these products you will be able to develop a brew that consists of your preferred colour, head retention, body, smoothness, and mouthfeel.
Of course, experimenting with malts is crucial to developing a fantastic brew, but if a beer needs a little boost in a certain area, there’s usually an un-malted cereal which can be used to save the day.