Craft Distillery Milling: In-house or Outsource?

By: Devin Mills – Dalkita Distillery Engineer

A craft distillery’s type, source and style of grain for its products is one of the first decisions a distillery makes, and it is a complex and multi-layered decision. Let’s look at the decision from the cost and facility complexity perspectives. The least expensive dollar/pound option for grain, results in more complex – more expensive – facility. Conversely, the more expensive dollar/pound option for grain, results in a less complex – less costly – facility.

The least expensive dollar/pound option for grain, results in more complex – more expensive – facility. Purchasing whole grain and milling (or not) in-house has benefits.

What Milling Can Bring to Your Product:

• Specialty grains like buckwheat, quinoa (not technically used in a “whiskey”), millet, teff, triticale, fonia, sorghum often only available as whole kernels
• No flavor loss through processing before arriving at distillery
• More control over flavor of product
• More control of the granule size to optimize product yields

The “Dark Side” of Milling In-House:

• Additional expense in milling equipment and physical facilities
• More ventilation required
• Added personnel protection equipment
• Added housekeeping duties to entire facility
• Time required to mill grain
• Consistency from batch to batch – sometimes grind setting will need to be adjusted between deliveries of the same grain dependent upon nitrogen content and dryness
• Increased energy usage for whole kernels and larger grinds requiring longer mash times
• Decreased mashing yields using whole kernels and larger grinds
• Potential over-milling contributes negative characteristics to final product

The more expensive dollar/pound option for grain, results in a less complex – less costly – facility. Purchasing pre-milled, rolled or flaked grain also has benefits.

The Lighter Side of Pre-Milled Grain:

• Time – Grain arrives at distillery ready for mashing
• Grain size and easy access to enzymes and starch molecules make mashing quick and easy
• A level of consistency from batch to batch
• Lower equipment and facility cost – bulk storage (S1) cheaper to construct than hazardous (H2) occupancy
• Cleaner – no combustible dust issues
• Quieter – no additional noise added to production floor
• Safer – no staff interaction with milling equipment, less risk for accidents

The Negatives of Pre-Milled:

• Narrower selection of grains to choose from
• Specialty grains hard to source in a pre-milled form
• Some flavor loss occurs during processing
• Less control over flavor profile of final product

There are positives and negatives with each decision. What is the right play for one distillery is not necessarily a good fit for another. Consider what you want to accomplish with your product, process and brand. From a design and construction standpoint – milling grain is for the craftiest of the craft producers among the industry. It may be a no-brainer for the product you are trying to create. Whatever direction you go in – a safe facility is a necessary and achievable goal.