The Process of Malting Millet for Brewing

Malting millet for brewing is a specialized process that transforms this small-seeded grain into a key ingredient for beer production. You may already know that malt serves as the sugar source necessary for fermentation. While barley has been the traditional grain of choice, millet offers a unique alternative, especially for those looking to produce gluten-free beers.

The malting process involves three fundamental stages: steeping, germination, and kilning. Each is crucial for converting millet’s starches into fermentable sugars and developing the flavors and aromas characteristic of malt.

Millet grains soak in water, then spread on a flat surface to germinate. After a few days, the sprouted grains are dried for brewing

During the steeping phase, the millet grains absorb water, triggering germination. This is where the grain begins to sprout, activating enzymes that break down starches into simpler sugars.

Millet’s ability to retain a good protein content plays a role in the quality of the final malt, with protein levels in millet typically ranging between 11.3% and 12.7%.

Germination is closely monitored and halted at the optimal time to ensure maximum enzymatic activity without exhausting the grain’s resources.

Kilning is the final step where you carefully dry the germinated millet to stop the growth process and lock in the desired malt characteristics. This stage also contributes to the color and flavor profile of your malt, affecting the overall taste of the beer.

In the case of millet, the malting loss — the difference between the starting grain weight and the final malt weight — is an essential factor to consider and averages around 10%.

Mastering the malting of millet can open doors to a diverse range of brewing possibilities, offering new flavors and catering to those seeking gluten-free options.

Basics of Malting

Millet grains soak in water, then spread on a malting floor to germinate. They are turned regularly to prevent overheating and mold growth

In exploring the essentials of malting, you’ll uncover the transformative process that turns simple grains into rich foundations for brewing.

Defining Malting

Malting is a fundamental practice in your journey to create beer, focusing on preparing the grain for fermentation. This process activates vital enzymes needed to convert the grain’s starches into fermentable sugars.

Through a series of steps—namely steeping, germination, and kilning—raw grains become malted, providing the fermentable base for your beer.

Grains for Malting

The selection of grains is a pivotal decision in the malting process, as each type of grain imparts unique flavors and properties. Common cereals used include:

  • Barley: Known for its husk and enzyme-rich composition, making it a traditional choice.
  • Wheat: Offers a distinctively light and cloudy appearance to some styles of beer.
  • Millet: A gluten-free option that is rising in popularity for its adaptability in brewing.
  • Sorghum: Another gluten-free cereal often used in African brewing traditions.
  • Rice: Typically provides a light flavor and is used in lighter beers.
  • Buckwheat: An alternative grain that is not part of the wheat family and is gluten-free.
  • Spelt: An ancient grain related to wheat, known for its nutty flavor.
  • Maize: Often used in lighter lagers for its subtle sweetness and efficiency.
  • Rye: Delivers a spicy note and a rich, hearty profile.

Each grain has its own germination and kilning requirements, which must be expertly controlled to produce malted grains that are optimal for brewing.

Malting Stages

Malting transforms millet into a form suitable for brewing, focusing on moisture control and temperature management through three main stages: steeping, germinating, and kilning. Each stage is critical for developing the flavors, colors, and fermentable sugars necessary for beer.


Objective: Increase moisture content in grains to initiate sprouting.

  • Process:
    • Start by submerging millet in water to hydrate the kernels.
    • Typical steeping time ranges from 24 to 48 hours, with intermittent air rests to prevent excessive water absorption.
    • Aim for a moisture content of around 42-46% to prepare for germination.


Objective: Activate enzymatic activity to convert stored starches into fermentable sugars.

  • Process:
    • Maintain a stable temperature, usually between 16-20°C (60-68°F), to support optimal enzyme action.
    • Turn the grains regularly to ensure even growth of rootlets and to dissipate carbon dioxide.
    • After a few days, typically between 3 to 5 days, the germination is halted once the desired modification is achieved.
    • At this point, careful monitoring is key; you’re looking for a balance where the millet’s husk remains intact while rootlets appear.


Objective: Halt germination process and develop malt flavor and color.

  • Process:
    • Slowly raise the temperature to dry out the millet, reducing moisture content to about 5%.
    • Initial drying is at lower temperatures to evaporate water gently.
    • Final drying can include higher temperatures to add specific roasted flavors and colors.
    • Temperature and time vary depending on the desired malt characteristics, with higher temperatures creating darker colors and more robust flavors.

Malt Types

Millet grains soak in water, then spread on a malting floor to germinate. They are turned regularly to ensure even germination. After a few days, the germinated grains are dried in a kiln

In brewing, malts are categorized into two overarching types that serve distinct purposes in influencing the beer’s color and flavor profile.

Base Malts

Base malts form the foundation of your brew, providing the necessary enzymes and sugars for fermentation. They constitute the majority of the grist and are lightly kilned, preserving the enzymatic power. The main varieties include:

  • Pale Malt: A versatile choice with a mild flavor, it’s ideal for a wide array of beers.
  • Pilsner Malt: With a lighter color and a delicate taste, it’s essential for brewing traditional Pilsner beers.
  • Munich Malt: Offers a maltier flavor and is perfect for darker lagers and ales.
  • Amber Malt: Known for adding a biscuity taste and rich amber hue to your final brew.

Specialty Malts

Specialty malts are used in smaller quantities to impart specific colors, flavors, and textures. These malts are further processed to enhance particular attributes:

  • Caramel/Crystal Malts: These malts are stewed and then kilned, creating sugary, toffee-like flavors and contributing to the sweetness and body of the beer.
  • Roasted Malts: Including options like chocolate malt, these are kilned at higher temperatures to yield darker colors and robust flavors such as coffee or chocolate.
  • Honey Malt: This subtly sweet malt imparts a honey-like taste and aroma, without overwhelming the beer.
  • Specialty Munich: A more intense version of Munich malt, increasing the richness of the malt character in your beer.

The Science of Malting

Malting is a fine balance between art and science, where you manipulate grain to make it suitable for brewing. Through the malting process, complex carbohydrates in millet are broken down into fermentable sugars, proteins are modified, and the grain is readied for the production of beer with distinct flavors and aromas.


During modification, the physical and chemical structure of millet grains is altered. This part of malting ensures that the grain’s endosperm becomes accessible, which assists in converting complex carbohydrates into simpler sugars.

Modification is critical as it affects the malt’s friability, the ease of milling, and the mash’s filtration efficiency. Advanced modification results in higher availability of starches for enzymatic breakdown.

Enzymatic Processes

Enzymatic activity in millet is pivotal for the malt quality. Enzymes such as amylase and protease play significant roles.

Amylases, both α and β, catalyze the hydrolysis of starch into sugars, which are essential for fermentation. Proteases break down proteins into amino acids, improving yeast nutrition, and influence the beer’s foam stability.

Proper control of enzymatic processes ensures the production of desirable fermentable sugars and amino acids.

  • Key Enzymes:
    • Amylase: Converts starches to sugars.
    • Protease: Breaks down proteins into amino acids.

Chemical Changes

The chemical changes in the malting process lay the groundwork for the flavor, color, and aroma of your beer.

As enzymes break down proteins and starches, a variety of sugars are formed, granting the yeast the necessary components for fermentation.

  • Sugars Generated: Maltose, Glucose, Fructose, Maltotriose.
  • During kilning, the application of heat halts the germination process and adds to the color and flavor of the malt. A careful balance is struck to preserve the enzymes that are so vital for the mashing process.

Malting Equipment and Techniques

As you explore the malting process for brewing, understanding the equipment and techniques used across various systems is fundamental.

Your choice of method will affect the flavor of your brew and the efficiency of your malting.

Traditional Methods

In traditional malting, you will encounter primary equipment such as floor malting rooms.

This involves spreading grains, such as millet, on a malting floor where they germinate. There’s significant labor involved in turning the grains periodically to maintain a consistent temperature and moisture level.

Floor malting is time-intensive and offers you a hands-on approach to control the malting process.

Modern Systems

Modern malting employs a variety of advanced equipment to increase efficiency and reduce labor.

The heart of these systems is often a rotating drum malter, which automates the turning of the grains for germination.

Temperature and humidity control is meticulously regulated, providing you with more consistent malt quality.

Another key component of modern malting is automation in both the steeping and drying phases, reducing the labor intensity and allowing for large-scale production.

Home Malting

If you’re homebrewing, your malting setup is likely smaller and more manual.

You might use simple equipment like plastic buckets for steeping and home-made boxes with perforated bottoms for germination and drying.

The process takes more of your time and attention, especially in maintaining the right temperature and humidity.

However, home malting can be a rewarding experience, giving you the freedom to experiment with the malting process.

Post-Malting Processes

Millet grains spread on a malting floor, turning regularly, as they germinate and dry, ready for brewing

After malting, your millet grains are now malted and ready for the subsequent stages critical for ensuring their quality before brewing. These steps are essential for maintaining the integrity of the malt and preparing it for a smooth transition into the brewhouse.

Cleaning and Sorting

Once the malting process is complete, it’s crucial to remove impurities from the malted grains.

During the malting process, rootlets develop and these must be detached because they carry no fermentable sugars and can contribute off-flavors to your beer.

  • Cleaning: Carefully eliminate any foreign materials such as stones, and dirt, along with the rootlets. This is typically done using a combination of sieves and air blowers.
  • Sorting: The goal here is to ensure a uniform batch of malted millet.
  • You’ll want to sort the grains based on size and color, removing any grains that are broken or discolored.
  • Consistency is key, as it ensures uniformity during the mash.

Storage and Handling

Proper storage and handling of malted grains preserve their quality until you’re ready to use them in the brewhouse.

  • Temperature: Store your malted millet in a cool, dry place.
  • The ideal storage temperature should be below 20°C (68°F) to prevent any premature germination or spoilage.
  • Moisture: The grains should be stored at a low moisture content, typically around 4% to 6%, to prevent mold and bacteria growth.
  • Husk: Intact husks are vital as they aid in the filtration process during brewing. Handle your malt gently to maintain husk integrity.
  • Storage: Use breathable containers like cotton sacks or bins that allow for air circulation to prevent moisture buildup.

Impact on Brewing

Millet grains soaking in water, then spread out to sprout and dry, before being roasted for malting process

The malting process of millet significantly shapes the beer you brew, influencing everything from flavor profiles to the final alcohol content. Here’s a closer look at how malting impacts the brewing process.

Flavor Contribution

Your choice of malted grain is a primary determinant of your beer’s flavor.

Millet malt, in particular, imparts a neutral flavor that serves as a clean canvas for other ingredients.

During the malting process, the activation of enzymes breaks down proteins and starches, contributing subtle flavor nuances.

These can range from sweet to slightly nutty, ultimately enriching the complexity of your beer.

Influence on Beer Body and Color

The body of the beer, perceived as its fullness or thickness, is partially attributed to the malting process.

Millet malt, with its efficient conversion of starches to fermentable sugars, can generate a moderate body, making your beer neither too heavy nor too light.

Additionally, the kilning stage of malting millet affects the beer’s color.

Lightly kilned millet can produce a pale hue, while prolonged or intense kilning can result in deeper amber tones.

Fermentation and Alcohol Production

Malted millet plays a crucial role in fermentation, the stage in beer brewing where yeast converts sugars into alcohol.

The malting process ensures that you have sufficient fermentable sugars for the yeast to work effectively.

A smooth fermentation process leads to optimal alcohol production, and ultimately, a well-crafted beer.

It’s important to note that a proper balance between the enzymes and the fermentable sugars from millet is necessary for successful brewing, affecting everything from the beer’s potential alcohol content to its filtration characteristics.

Alternative Grains and Gluten-Free Malting

As you explore homebrewing, particularly gluten-free options, it’s essential to understand the available grains and the malting process that suits them. This will ensure your brewing endeavors meet dietary requirements without compromising on quality.

Gluten-Free Options

If you’re delving into the world of gluten-free brewing, millet, sorghum, buckwheat, and rice present themselves as viable alternative grains.

Each of these grains offers unique properties that contribute to the character of the final beer product.

  • Millet: Known for its light flavor, millet is a popular choice for gluten-free malting. It undergoes a malting process similar to barley, which includes steeping to initiate seed growth, germination to develop enzymes necessary for brewing, and kilning to halt germination while preserving these enzymes.
  • Sorghum: Sorghum is a staple in gluten-free beer brewing. It doesn’t require malting and often serves as a syrup in brewing, though malted versions are also available. Its neutral profile makes it an excellent base for flavor experimentation.
  • Buckwheat: Despite its name, buckwheat is not related to wheat and is gluten-free. It imparts nutty and earthy tones to beer. When malted, buckwheat can add body and head retention to your homebrew.
  • Rice: Typically used as an adjunct in brewing, malted rice can also serve as a base grain for gluten-free beers. It provides a lighter color and a crisp flavor profile to the beer, making it a desirable ingredient for those looking to brew a gluten-free beer with a clean finish.

Frequently Asked Questions

In this section, you’ll find answers to common queries about the malting process for millet as it relates to brewing.

What are the critical steps involved in the malting process for beer production?

The malting process for beer production includes steeping, which initiates germination, followed by a germination phase where enzymes are activated, and finally, kilning where the malt is carefully dried.

How does the kilning stage influence the flavor of malted millet in brewing?

The kilning stage halts germination and develops flavor and color by toasting the millet to varying degrees.

The kilning temperature and duration can result in different malt profiles ranging from light to dark, with corresponding flavor differences.

What is the role of steeping during the malting of grains for brewing?

Steeping involves soaking the millet grains in water, which revives the dormant seed, initiating the germination process.

This helps in activating the enzymes necessary for converting starches into fermentable sugars.

How does malting millet differ from malting barley in the context of beer brewing?

Malting millet typically requires adjustments in the malting process due to its smaller grain size and different protein structure compared to barley.

This necessitates careful handling and process alterations to achieve optimal germination and kilning.

Can you explain the importance of malting in the overall beer production process?

Malting is crucial in beer production as it develops the enzymes required to convert the grain’s starches into sugars, which are then fermented by yeast to produce alcohol and carbon dioxide, contributing to beer’s taste and character.

How long does the complete malting cycle take for millet intended for brewing?

The malting cycle for millet intended for brewing typically spans over a week. The duration varies depending on the specific conditions set for steeping, germination, and kilning to achieve the desired malt quality.

Follow Us
Cassie brings decades of experience to the Kitchen Community. She is a noted chef and avid gardener. Her new book "Healthy Eating Through the Garden" will be released shortly. When not writing or speaking about food and gardens Cassie can be found puttering around farmer's markets and greenhouses looking for the next great idea.
Cassie Marshall
Follow Us
Latest posts by Cassie Marshall (see all)