Author: Matt Del Fiacco

Brewers commonly boil wort for between 60 and 90 minutes depending on the base malt used, though some opt for even longer boils to encourage Maillard reactions that are believed to add depth of malt character and a darker color in the final beer. Those craving the full, rich, caramel flavors found in styles like Barleywine or Scottish-style ale have been known to boil wort for 2 hours or longer. In fact, on a recent trip to the famous Traquair House Brewery in Scotland, I learned most traditional Scottish breweries boil wort for about two hours in large copper kettles, which is contrary to the popular belief they boil down their wort over a much longer period of time.

I’m passionate about Scottish-style ale and brew them fairly often, so learning that the quintessential deep flavors they’re known for are achieved with but a mere 2 hour boil was pretty surprising, especially given the typically simple grainbills. It’s possible the use of copper kettles plays a role, as their high conductivity may lead to a stronger Maillard reaction. However, considering the non-significant results of prior xBmts on boil length, I became interested in the impact an extended boil has on beer and put it to the test!



| PURPOSE |

To evaluate the differences between a 60 minute boil and 180 minute boil in otherwise similar beers.

| METHODS |

For this xbmt, I went with a somewhat paler version of a Scottish Heavy recipe I’ve been tweaking for quite some time.

Òrain

Recipe Details Batch Size Boil Time IBU SRM Est. OG Est. FG ABV 5 gal 60 min 16.3 IBUs 5.7 SRM 1.040 1.011 3.8 % Actuals 1.04 1.012 3.7 % Fermentables Name Amount % Golden Promise (Simpsons) 7.187 lbs 96.64 Crystal, Medium (Simpsons) 4 oz 3.36 Hops Name Amount Time Use Form Alpha % East Kent Goldings (EKG) 22 g 60 min Boil Pellet 5 Yeast Name Lab Attenuation Temperature Tartan (A31) Imperial Yeast 73% 65°F - 70°F Notes Water Profile: Ca 50 | Mg 5 | Na 5 | SO4 44 | Cl 70 Download Download this recipe's BeerXML file

I got starter of Imperial Organic A31 Tartan yeast going almost a few day ahead of time.

I started my brew day by collecting the full volume of brewing liquor for both batches, making sure to account for boil off rate so both batches would end up with the same OG. After adjusting each to my desired profile, I turned on the heat.

While the water was heating, I weighed out and milled the grains for each batch.

Once strike temperature was reached, I incorporated the grains and gently stirred before making sure both hit my intended mash temperature.

I took pH readings 15 minutes into each mash and found both were right where I wanted them to be.

Once each mash was finished, I lifted the grains and let them drain until the proper volume was reached. I added the bittering hops to the 60 minute boil wort as soon as it reached a boil.

I added the bittering charge to the 180 minute boil batch after 2 hours of boiling, at which point the 60 minute boil batch was chilled and in the fermenter. At the completion of the boil, I chilled the wort using my CFC and racked it directly to a fermentation keg.

Hydrometer measurements revealed both worts hit my 1.040 OG target.

The worts were placed next to each other in the same temperature controlled chamber where they were left alone for a couple hours. Once both were sitting at my target fermentation temperature of 66°F/19°C, I split the yeast starter equally between then attached blowoff tubes.

Fermentation dwindled a week post-pitch and I let the beers sit a few more days to allow for clean-up of any off-flavors. Hydrometer measurements after 10 days showed both were sitting at the same 1.011 FG.

I cold crashed the beers and pressure transferred them to serving kegs before hitting them with a quick round of burst carbonation.

Following 2 weeks of conditioning in my kegerator, the beers were ready to serve to participants.

| RESULTS |

A panel of 22 people with varying degrees of experience participated in this xBmt. Each taster, blind to the variable being investigated, was served 2 samples of the 60 minute boil beer and 1 sample of the 180 minute boil beer in different colored opaque cups then instructed to select the unique sample. At this sample size, a total of 12 (p<0.05) correct selections would have been required to achieve statistical significance, while only 10 tasters (p=0.16) chose the different beer, indicating tasters were not able to reliably distinguish a Scottish Golden Ale made with a standard 60 minute boil from one made with an extended 180 minute boil.

My Impressions: In three blind triangle tests, I was able to select the odd-beer out twice, but I have to admit that I was largely guessing. I think that the 180-minute boil beer was slightly more crisp, but I honestly had an incredibly hard time telling these beers apart. They were identical, to my palate, in terms of of appearance, aroma, and flavor.

| DISCUSSION |

Brewers often discuss extending the boil length as a way to encourage Maillard reactions thereby imparting a deeper malt character and darker color to the finished beer. It made sense to me wort being in contact with heat longer could produce this effect and I admittedly expected the 180 minute boil beer to be perceptibly different than the 60 minute boil beer. Of course, this wasn’t the case, participants in this xBmt were unable to reliably distinguish one beer from the other, and my own biased performance was no better than theirs.

It would appear that when controlling for evaporation losses, length of the boil has minimal if any impact on overall beer character. It’s entirely likely that, given the same starting volume of liquor, a beer produced with a 180 minute boil would look and taste different than one boiled for only 60 minutes. However, the results of this xBmt along with those of prior xBmts on this variable seem to suggest any such differences would more than likely be a function of wort condensing due to evaporation loss than caramelization or Maillard reactions from a longer boil. While I’ll continue boiling as usual, this experience has inspired me to continue exploring the impact of boil length, particularly under unique conditions such as when a copper kettle or a more powerful heat source is used.

If you have thoughts about this xBmt, please feel free to share in the comments section below!

Support Brülosophy In Style!

All designs are available in various colors and sizes on Amazon!

Follow Brülosophy on:

If you enjoy this stuff and feel compelled to support Brulosophy.com, please check out the Support Us page for details on how you can very easily do so. Thanks!

Advertisements

Share this: Facebook

Twitter

Pinterest

Tumblr

Email



Like this: Like Loading...