Malted maize is a great malted adjunct for use with brewing or distilling. In the brewery, it can add a crisp flavour and dry finish, perfect for that summer lager. In distilling, it can be used for a traditional Bourbon Whiskey as at least 51% of the grist.
Malting the maize adds a unique component that is not found when using flaked or maize grits to get our added sugars. The malting process itself adds a lot of depth to the maize flavour along with the benefit seen by the extra enzyme activity (cooking aside). The additional protein breakdown is great if you are using 5-10% maize in a recipe to lighten the colour and add a bit of flavour. But for bigger maize grist some more work is required to get the most out of the malted maize.
The issue with maize in brewing has always been the high gelatinization temperatures required to access all the available starch. Where barley, wheat and rye will all gelatinize at standard mash temperatures. Maize requires up to 75 degrees in order to access all the available starch. This then creates the problem of destroying the enzymes needed to break down those newly available starches.
Malting maize is a partial answer to this, but as we are learning, it still does not make for a simple grind and mash. We will continue to malt and learn more about maize and how it can be best utilized and produced through the maltings. But in the meantime, there is some additional work to using the maize. Especially if you are looking to use it for distilling at a high percentage of the grist.
For best utilization of the malted maize, we recommend a pre-cook step after milling. We had the most success in the lab by cooking the maize in three times its weight in water and slowly boiling for 10-20 minutes then allowing it to cool down to mashing temp. Then add this porridge to the mash itself.
A quick pre-soak will also work well if you are using a smaller amount of maize (less than 10%). Simply pour boiled water over the crushed maize and allow to sit while you get the rest of your brewing set up. Then add this portion to the mash. Just remember to consider the extra water when doing your calculations!
Gladfield Malt Production Manager and Maltster