Why does my beer taste like bacon?

Question

I recently brewed an oatmeal stout that has distinct bacon notes to it, both in the nose and in the flavor. What could be causing these flavors? This bacon-ness isn't disagreeable; it's actually quite pleasant in this beer. It's not rancid or meaty. It's a smoky note that smells bacon-like. It's just that I didn't expect it and I don't know what caused it. It likely came from some of my dark malts, but I can't say for sure. Maybe it came from the yeast. I dunno.

The beer is still very young - I just now racked the two week old beer into a secondary fermenter to add some cold-brewed coffee and cacao nibs soaked in Maker's Mark to make it a breakfast stout. It had the bacon-ness when I tasted it when fermentation finished and it still has the flavor today, prior to racking onto the flavorants.

Here is my recipe and notes:

• 14 lbs US 2-row pale malt
• 1 lb, 6 oz flaked oats
• 1 lb chocolate malt
• 12 oz roasted barley
• 9 oz black patent
• 7 oz crystal 120
• 1 oz Nugget
• 0.5 oz Mt. Hood (30 min)
• 1/8 tsp yeast nutrient (10 min)
• 1/2 tsp Irish moss (10 min)
• 0.5 oz Mt. Hood (0 min)

• 2 Packages SafAle S-04, proofed in 100F H₂O

• Mash all grains at 153F for 60 minuets

• After collecting the first runnings, batch sparged with 188F water, which brought mash temp to 168F.
• Boiled for 90 minutes.
• OG: 1.080
• FG: 1.022
• The beer fermented very quickly. I brewed on Saturday, 01/22/11 and it had dropped from 1.080 to 1.022 by Monday evening, 01/24/11. Even so, the fermentation temperature never went above 72F.

Edit: I meant to put some info about my water/mash chemistry, in case that's important. For this beer I did not make any water adjustments (except for dechlorination). No acids, no carbonates, no salts. I just went with nine gallons of my tap water with 1/2 tsp of potassium metabisulfite to dechlorinate.

I was concerned that I couldn't brew such a dark beer without adjusting my water because Palmer's nomograph suggests I can brew beers between about 9 and 18 SRM without any adjustment. This beer comes in at 52 SRM. However, after mashing in and waiting 15 minutes, I tested my mash pH with a pH meter and it read 5.27, so I did not adjust it. Here are the values from my water report:

• pH: 8.3
• Ca: 28 ppm
• Mg: 6.2 ppm
• Na: 30 ppm
• SO₄: 65 ppm
• Cl^-: 31 ppm
• CaCO₃: 61 ppm

Answer 1

The bacon flavor could be coming from a couple of different things but it would be hard to pinpoint exactly without a sample. Here are a few things it could be.

The first thing is that you can get a smoky flavor from the chocolate malt, the roasted barley, and other dark roasted grain, this happens when you use a larger percentage of these dark grains in your malt bill. This is the most likely scenario. There could also be some contributing factors in the water profile but not likely.

Secondly, like Denny mentioned above, it could be an infection that is producing phenols that are perceived as smoky, but since your wife detected this flavor in the boil kettle it's most likely not the case. You can also get these types of phenols from oversparging, sparging above 6.0 pH, and sparging above 170F. It's possible when you added the batch sparge water it brought the pH above 6.0 if your water is highly buffered.

There is also the possibility that there was still some chlorine left in your brewing water. You can confirm this by using test strips.

Answer 2

It's likely an infection. Both pedio and lactic infections can produce smoky phenolics. Unfortunately, I have experience with that!

Answer 3

My first guess (and this is really nothing but a guess) would be the mix of chocolate, roasted & black patent barley. Different mixes are going to give you different flavors -- coffee, chocolate, dark-roast, etc. This mix is the magical 'bacon' mix.

Rauchbeers can also taste bacon-y, but they are using smoked malts. None of the malts in your beer are smoked, but the high kilning temperatures could be leading to some flavor compounds similar to bacon.