In the world of homebrewing, even the slightest change in ingredients is often believed to yield significant differences in the final product. However, sometimes the perceived impact of specific malts does not align with sensory reality. In a recent exBEERiment conducted by Brülosophy contributor Will Love, where two Altbiers were brewed side-by-side, one with Carafa I and the other with roasted barley, the results were strikingly similar. Neither Will himself, scoring 3 out of 6 correct identifications, nor a panel of 20 blind tasters, with only 7 accurately distinguishing the unique sample (falling short of the 11 needed for statistical significance), were able to reliably tell the beers apart. This challenges the common assumption that these two specialty dark malts contribute distinctly different characteristics, particularly when employed in an Altbier recipe.
This experiment, detailed in the accompanying video, delves into a common concern among brewers: the potential for roasted barley to impart undesirable burnt or acrid notes. Carafa I, a dehusked malt, is frequently suggested as a smoother alternative. Yet, when put to the test, the two malts proved to be virtually indistinguishable in this Altbier. The implications of these findings are substantial for homebrewers, potentially simplifying ingredient choices and challenging long-held brewing dogma.
Unpacking the Differences: Carafa I vs. Roasted Barley
Dark ales typically derive their deep color and roasty undertones from highly kilned malts. Among the most popular choices is roasted barley, a malt known for its intense color contribution and often described as imparting coffee or chocolate notes, sometimes with a sharper, more astringent character due to the presence of its husk. Conversely, Carafa I, a specialty malt from Weyermann, is distinguished by being dehusked or “sanded.” This process is designed to mitigate the harsh, acrid, or burnt flavors that can be associated with roasted malts containing husks, thereby contributing a smoother, less bitter roast profile.
The choice between these malts often stems from a desire to fine-tune the flavor profile of dark beers. Many brewers actively avoid roasted barley when aiming for a clean, nuanced roast, opting for huskless varieties to prevent any perceived ashiness or smokiness. For this particular experiment, the Carafa I utilized had an SRM (Standard Reference Method) value of approximately 320, while the Briess roasted malt used was around 400 SRM. While a slight color difference was noted in the raw malts, it was theorized whether this would translate into a perceptible difference in the final Altbier, a style that, while amber, is known for its clean, crisp profile where off-flavors might be more easily detected.
Crafting the Altbier: A Foundation for Comparison
The experimental beers were brewed as Altbiers, a traditional German amber ale known for its balanced malt character, moderate bitterness, and clean fermentation profile that often mimics a lager. This style was deemed ideal for the experiment because its inherent simplicity offers “nothing to hide behind,” making any potential differences between the malts more apparent. The recipe was developed as part of a Brülosophy Club collaboration, where parameters are often voted upon, though “bending the rules is encouraged.”
The malt bill was structured to highlight the specialty malts being tested:
- Llano Pilsner Malt: 10 pounds (85% of the grist), serving as the base malt.
- Munich Malt: 1 pound (8.5% of the grist), contributing to the amber color and malty depth.
- Caramunich Malt: 4 ounces (2% of the grist), for additional caramel notes and color.
- Carafa I OR Roasted Barley: 8 ounces (4.3% of the grist), providing the dark roast character and the primary variable for the experiment.
The brewing process itself was executed with meticulous attention to consistency to ensure that the only variable was the dark specialty malt. A standard mash schedule was followed, with the grains being mashed at 152°F (66.7°C) for 60 minutes. A no-sparge technique was employed, simplifying the process and potentially offering a slightly richer body. Hops were added at specific intervals:
- Magnum: 15 grams at 60 minutes for bittering.
- Tettnanger: 55 grams at 30 minutes for flavor and aroma.
- Tettnanger: 55 grams at 5 minutes for late aroma.
Throughout the brew day, precise measurements and careful labeling were paramount. The use of a digital refractometer was observed for quick and accurate gravity readings, minimizing wort loss. Furthermore, a modern glycol chilling system was utilized to rapidly cool the wort to pitching temperature, ensuring consistency in fermentation initiation. Both batches were fermented under identical conditions: four days at primary fermentation temperature, followed by a rise to 68°F (20°C) for another four days. As expected, the final gravity for both beers was identical at 1.011, which was anticipated given the minimal fermentable sugars contributed by such small quantities of highly kilned malts.
The Verdict: Unseen Differences in Altbier
Visually, the two Altbiers were described as “pretty much identical,” with any subtle differences in darkness requiring specific lighting to discern. Over time, both beers cleared beautifully, displaying the characteristic amber hue expected of the style. However, the true test lay in the sensory evaluation.
The core of the Brülosophy methodology revolves around blind triangle tests, where tasters are presented with three samples, two identical and one unique, and asked to identify the outlier. Will Love’s personal triangle test resulted in 3 out of 6 correct identifications, a score that, while not terrible, falls within the realm of chance and is not considered statistically significant. He noted that the beers were “really similar” on aroma and taste, perceiving only a “touch more roastiness” in one sample during his initial attempts. The difficulty in distinguishing them was evident, as Will admitted to being “glad to be wrong again” when unable to identify the variable.
A larger panel of 20 blind tasters was then presented with the Altbiers. For the results to be deemed statistically significant, 11 of these tasters would have needed to correctly identify the unique sample. However, only 7 individuals were successful. This outcome, a mere 35% correct identification rate, further cemented the lack of a perceptible difference between the Carafa I and roasted barley Altbiers. It was observed that the perceived “subtle, nutty roast character” with “no hint of coffee, dark chocolate,” was consistent across both versions, suggesting that the feared acridity or ashiness from the roasted barley simply was not present in this application.
Broader Implications for Homebrewers
Despite the lack of a statistically significant difference in taste perception, the roasted barley Altbier did achieve recognition, securing a bronze medal in the “Hot and Humid” competition in Florida. This accomplishment suggests that even the version made with the “sacrilegious” roasted barley was a “fairly okay representation of the style,” capable of impressing seasoned judges.
The findings of this exBEERiment offer profound practical takeaways for homebrewers. When formulating an Altbier recipe, or indeed many other dark beer styles, the perceived need to meticulously choose between Carafa I and roasted barley for fear of off-flavors may be largely unfounded, especially when used in similar proportions (4.3% of the grist in this case). The experiment demonstrates that, at least in an Altbier, any “undesirable burnt note” from roasted barley was not detectable by tasters, including an experienced brewer.
This provides considerable flexibility for homebrewers. If a brewer has roasted barley on hand, there appears to be no significant disadvantage to using it over Carafa I. The decision could then be driven by convenience, cost-effectiveness, or simply what is available at the local homebrew supply store. The experiment encourages homebrewers to challenge preconceived notions about ingredients and to rely on sensory evaluation rather than assumptions. While Black Patent malt is known for more intense acrid notes, and previous Brülosophy experiments have explored its impact, the results from this Carafa I vs. roasted barley trial underscore that not all dark roasted malts will impart readily discernible differences in every beer style, especially when incorporated thoughtfully into a balanced recipe.
ExBEERiment Q&A: Your Altbier Queries Distilled
What was the main purpose of this brewing experiment?
This experiment tested whether people could taste a difference between two dark brewing malts, Carafa I and roasted barley, when used in an Altbier recipe.
What are Carafa I and Roasted Barley?
They are types of specialty malts used by brewers to give dark beers their color and roasted flavors. Carafa I is dehusked, aiming for a smoother taste, while roasted barley includes its husk.
Why do some brewers choose Carafa I instead of Roasted Barley?
Some brewers believe Carafa I prevents harsh, burnt, or acrid flavors that they associate with the husk of roasted barley in their beers.
What was the surprising result of the taste test?
The tasters, including the brewer, could not reliably tell the difference between the two Altbiers, indicating both malts produced very similar results in this beer style.
What does this experiment mean for homebrewers?
It suggests that for certain dark beer styles like Altbier, homebrewers may have more flexibility in choosing between Carafa I and roasted barley without a significant impact on the final taste.
