By Kaeley Kindrachuk, AT, B.App.Sc., Crops Extension Specialist, Outlook and Mitchell Japp, MSc, PAg, Provincial Specialist, Cereal Crops
There are many considerations that go into malt barley production. From field to brew house, correct timing and attention to detail throughout the process are important.
In the Field: Harvest Considerations
Malt barley must be delivered to the maltster in a living state because it needs to germinate during the steeping process in the malt house. This makes malt barley a high-priority as harvest gets closer. At least 95 per cent of the kernels must germinate.
There are some limitations on management tools that can be used on malt barley crops. For example, pre-harvest glyphosate, which is registered for perennial weed control, is not used on malt barley crops. Nationwide, malt houses refuse to take barely that has been treated with glyphosate. Glyphosate can interfere with germination, so for the same reasons it should also not be applied to crops intended for seed.
Alternatives to pre-harvest glyphosate for controlling perennial weeds in malt barley include planting the crop in a field that is relatively free of weeds or treating the fall regrowth after the malt barley has been taken off the field. When planting the malt barley, it is better to avoid fields with wild oat resistance because it is tough to separate.
It is essential to be prepared to harvest malt barley in a timely manner. Malt barley is often harvested earlier than other crops. It is important to watch the weather carefully because the quality can deteriorate rapidly in wet conditions. Chitting (pre-germination) can become an issue in wet conditions. Chitting may result in not meeting malt requirements, but not necessarily. If the crop does become chitted, work closely with the buyer to move it early in fall because the germination energy will decline more rapidly than sound barley.
Malt barley can be harvested at 16 per cent or even a little higher, then dried using aeration. Harvesting at higher moisture content may be more beneficial than waiting and increasing the chance of getting rain. If using a grain dryer, be careful about the temperature used (maximum recommended is 45 C air temp for malt). Barley is considered safe for storage in Canada at 13.5 per cent or lower.
Also, having higher moisture content while harvesting reduces or eliminates issues with peeling and cracking. Peeling and cracking become more problematic in hot, dry harvest conditions, when the grain is very dry. Peeling and/or cracking needs to be less than five per cent. If peeled, it will take on moisture at a different rate and germination will be uneven. If cracked, it will probably not germinate. It is important to adjust the combine as the relative humidity and temperature changes throughout the day.
There are pros and cons for both swathing or straight cutting. When swathing, look for a window where you will have enough days of drying to be able to combine it. Drying in swaths can even out moisture levels in the kernels. Leaving the crop standing for straight cutting is effective when the crop is uniform and reduces costs compared to swathing and weather-related risks compared to swathing.
While monitoring grain condition in storage and marketing are essential after the grain is in the bin, reviewing the year and lessons learned is valuable too. Comparing notes on what happened in fields that did and didn't make malt may provide indication on what can be done better next year to increase the likelihood of getting selected for malt. Take a look at the grade and notes received on uniformity, germination and plump. Were there differences? Check out the notes from our spring Crop Walk on how these can be manipulated for higher yielding, better quality malt barley. Doing trials on your own farm can help determine what works best under your farming management.
In the Malt House: The Malting Process
Malting, the process of using heat and water to initiate germination for brewing and distilling, is an age old business, however, it is more high tech now than ever – maltsters can control quality and timeframes really closely. There are a lot of steps along the way to ensure a quality product.
The first quality factor that maltsters look for is germination, as well as the plump and the peeled and cracked kernels. They also look for protein content at 12.5 per cent or lower because of how it malts and brews. Uniformity is important because you want things to happen evenly throughout the malting process. If there are vastly different thins and plumps, then hydration will happen at a different rate and the maltster will have difficulty controlling when to finish the germination stage.
The barley kernel uses the complex starch from the endosperm to start growing its shoot out of the ground. It is using that energy and as it uses it, it changes from a complex starch into a simple sugar that brewer's or distiller's yeast can use. That is the reason for malting, to turn complex starches into simple sugars, so the brew houses' yeast can use it. If the kernel does not germinate, then none of the modifications will happen. Without the germination process, the kernel becomes a WUG (Whole Unmodified Grain). This grain has had no modifications, so no enzymes and no biochemistry that is needing to happen has initiated.
At a boutique malt house like Maker's Malt, everything stays in the steeping vessel for the whole malting process. During the steeping, the kernels start to chit, which mean the rootlets start to emerge from the kernel within the first 24-48 hours. The kernels start hydrating from the 13.5 per cent moisture content barley is stored at to 45 per cent. The water needs to go through the whole endosperm. If the whole thing is not hydrated, the kernel becomes a PUG (Partial Unmodified Grain) which has been modified until the point where hydration didn't quite make it from the chitting end to the distal end of the kernel.
The whole machine consists of the steeping tank, a big blower, a big furnace, a chiller loop and a misting chamber. These attachments allow for total control over the whole environment – temperature, humidity and air flow control.
Finally, kilning happens, which means to dry the grain down to 5% and add flavour and colour based on the type of product they are trying to make and it is where they can be creative. Different flavours of malt are used in different types of beer production, such as chocolate or roasted malt. However, the base for essentially all beer is a basic pale malt.
For more information on the malting process, or growing malt barley:
- Search "malt barley" on this site;
- View the malt barley crop walks on Facebook; or
- Contact your nearest Crops Extension Specialist or the Agriculture Knowledge Centre at 1-866-457-2377.