Day in the Life: A Rahr Maltster
Day in the Life: A Rahr Maltster
A typical day...
The day is no different from the day before, or the day before it. For 24 years, the malthouse in Alix, Alberta has been providing brewers with a high-quality base malt produced from locally grown Alberta barley. The typical day for a Rahr Maltster begins no different than most of the working world, with a cup of coffee—no, not a beer just yet. Glossing over the uninteresting yet necessary supervisory, logistical and administrative duties, we can skip to what is most important, the malt. The ultimate responsibility of a Rahr Maltster is to ensure that nothing but consistent, high-quality malt is produced. A Rahr Maltster will perform a thorough tour of the malting tower at least once per day to gauge proper growth and modification of the barley throughout the processes of steeping, germination and kilning. The tour through our facility provides a useful framework to explain the malting process in more detail as well as the main job description of the Maltster at Rahr Malting Canada.
On any given day, there are seven batches at progressive stages throughout the malting process. The Maltster’s tour begins at the top of the malting tower where the steeping of barley occurs. The barley used for malting purposes is immensely important. It must be of a specified variety and must also fit into a rigorously defined range of quality parameters including protein, moisture and germinative capacity. Homogenous barley is introduced to water in steeping, thus activating simultaneous growth of the barley kernels in an effort to dramatically increase the internal moisture content. During steeping, the Maltster will analyze the moisture content of the barley to determine proper water uptake as well as visually assess root growth, known as chitting, to determine the consistency of growth. The steeping process uses water immersion and overhead sprays for water uptake. This is done in combination with air rests where carbon dioxide is removed while fresh air is introduced. It will take about 48 hours to complete the steeping process.
Next, the Maltster will tour through each of the four germination vessels where continued growth and important internal changes within the barley occur, referred to as modification. Within the barley kernel - cell walls and proteins are broken down to liberate starch and soluble proteins. Highly viscous materials, detrimental to the brewing process known as β-glucans are also continually broken down during germination. A large excess of enzymes capable of converting starches to sugars are generated, collectively referred to as the diastatic power of the malt. Starch-degrading enzymes convert starch to sugars during brewing, and along with soluble proteins, provide food and nutrition for yeast during fermentation in the brewery.
The Maltster is constantly seeking to grow the barley to an optimal level of modification. Under-modified malt will contain starch unavailable to the brewer as well as high levels of β-glucans. Malt that is overgrown will contain less extract potential (sugar) for the brewer, used up by the plant to produce roots/shoots—this overgrowth is referred to as malting loss. The Maltster uses a number of tools to determine the extent of modification during germination. The acrospire length, what would be the eventual stem of the plant, can be used as a guide to proper modification. On average, an acrospire length of roughly 1:1 ratio compared to the length of the kernel is desired. The Maltster will also perform what is called a “rub-out” of the kernel, looking for hard, under-modified regions to gauge extent of germination. In addition, a chew-test, internal moisture, and odour can all be used to give the Maltster as much information as possible. The germination phase of malt production generally takes about 96 hours after which the product is now referred to as “green malt”.
The Maltster will then proceed to the last stage of the malting process and enter the kilning vessel. Kilning uses hot, dry air to decrease the moisture content of the green malt, arresting further growth to achieve a stable final product. Enzymes are inactivated in the kiln which will be reactivated during brewing. The Maltster will achieve important colour and flavour attributes desired by brewers by modifying time and temperature kilning regimes.
Next, the Maltster will head to the malt laboratory where malt is analyzed for many different characteristics important to brewers. Examples of important analysis conducted in the lab include soluble protein percentage, colour, moisture percentage, and diastatic power. The lab will mimic wort production of a brewery to generate data for many of the analyses conducted. The Maltster will taste and smell the wort, looking for certain attributes and off-flavours as another tool to assess the malt. Sorry, no alcohol in the wort but closer to beer than coffee! The analysis from previous batches are used by the Maltster to give insight into adjustments for upcoming batches.
It is important to remember this is a biological entity being grown, no two batches are exactly the same. This is the main reason why the Maltster position is so important. The Maltster will make process changes, massaging controllable parameters to achieve desired growth and modification, and to generate malt characteristics desirable for the brewer. All of the information gleaned from the day will be taken into account when creating the recipe for tomorrow’s batch.
At the end of the work day, the Maltster is now able to sit down for a well-deserved beer that has used malted barley as one of its main ingredients. A delicious reward for another day spent as a Maltster.
Want more on malt? Check out our Expert Advice from Canada's Malting Barley Technical Centre.