Death by Dunkel Update

A couple nights ago I decided to bottle the oatmeal stout and wanted to transfer the dunkel for secondary fermentation. It's been twelve days and looked like active fermentation had slowed. This was noticeable by the lack of bubbles in the airlock. To my surprise when I peaked in I saw this:

Looks tasty, right? :) I'm no expert, but the yeast still looked pretty active to me. I grabbed a hydrometer reading just to see where I was in terms of gravity. It was right around 1.019. The Kolsch yeast took about two days to get started. On the side of caution I decided to let the beer ferment for another couple days.

I'm not 100% sold on the notion of secondary fermentation. The trouble and time it takes doesn't seem worth it for every batch. The main reason I've decided to get the dunkel off the trub is to try my hand at harvesting the yeast by washing and storing for future use. More on that tomorrow. In the meantime I want to discuss the efficiency of my first true partial mash.

The Home Brewing Wiki provides a good background on efficiency and how it relates to both all grain and extract brewing:

In extract brewing, the malt extracts that are used to provide
fermentables always yield a predictable amount of sugar. A pound of LME in a
gallon of water will yield 37 points of specific gravity, and a pound of DME
will yield 45 points (give or take a point or two, depending on the brand of
extract).

For grain mashing, the story is different. Various types of
malt yield different amounts of sugars, and there are many other variables that
also influence how efficiently your mashing and sparging procedures extract
sugar from malt. Because of these factors, the amount of sugar obtained from a
pound of malt can vary over a fairly wide range. The good news is that as long
as your procedures remain reasonably consistent from batch to batch, it is
possible to predict how much sugar you will get from your malt, provided you
know what your extraction efficiency is. Extraction efficiency is the ratio of
the amount of sugars you actually obtain, to the theoretical maximum amount of
sugars available. Because of the large number of variables involved, the only
way to really determine the extraction efficiency of your brewing system is by
trial and error.

Typical extraction efficiency in a homebrew setting is
in the 60-80% range.

So considering 60% to 80% is the typical range for efficiency, how did I fair? Luckily I found an efficiency calculator thanks to the fine folks of brewersfriend.com. Simply input your amount, gravity reading and ingredients to get the efficiency calculation:


Woohoo 83%!! It's still a little hard to believe considering it was my first attempt, but I guess I'm doing something right. I double checked all the ingredients input and I'm confident the hydrometer reading was accurate. I'm not going to argue... if I can consistently hit that mark I'll be a happy brewer. The only thing that confuses me is that I missed my OG by a couple marks. I would have assumed I would be dead on with that kind of efficiency.

Death By Dunkel - Partial Mash Brew Day

It took a while to get everything together, but I am finally ready to brew a true partial mash recipe. I already assembled the mash tun, but also needed a larger brew pot and immersion wort chiller to accommodate a larger boil quantity. The world of mashing means more attention must be given to the brewing process, but the trade offs are well worth it. Among them are more control over the flavor characteristics, the ability to brew with more grains and hopefully a better tasting beer.

I randomly stumbled across a partial mash recipe for a dunkel converted from all grain. This was perfect because I've been wanting to brew with munich malt and also was looking for a dunkel recipe. This isn't a true dunkel since I'm not lagering. The recipe calls for Wyeast's Kolsch strain, which is an ale yeast that is pretty darn close to a lager strain without being one. Per Wyeast's webiste: Used to produce quick-conditioning pseudo-lager beers. Special thanks to chainsawbrewing and janitorjerm of homebrewtalk.com for providing the recipe and conversion. The following is my partial mash process:

Grains! While I prepared everything the MLT was filled with 1 gallon of 170F water with the lid on. This was drained before the grains were added and used to heat up the LME. I did this so the temperature in the mash tun was already elevated to minimize any huge temperature fluctuations.

Let's mash! My strike water was right at 165F as the recipe suggests. I used a ratio of 1.25 quarts of water per pound of grain. Since I had 3.6lbs I ended up with close to 1.5 gallons as my volume for the mash.

I mashed for 60 minutes which gave me enough time to have a homebrew and go over some notes from my last brews. This night I enjoyed a 4C IPA and think it's getting better with age. YUM!

I checked the temperature about every twenty minutes. I was able to stay above 150F for the whole mash. I did add a bit of 165F water for good measures around the thirty minute mark.

A couple of vorlauf pours to allow the grain to separate a bit and get some grind out of the way.

Although it's hard to tell, but the wort is a much lighter and less grainy in this picture compared to the last. It confirms my steel/copper braid is holding up.

Spent grains for the compost.

My mash yielded 3.5 gallons with a gravity reading of 1.030. I still need to calculate my efficiency. I added another 3/4 gallons to bring my boil volume around 4.5 gallons

Boiling the wort chiller to sanitize it prior to use.

Overall I think the first true partial mash was a success. I still have some kinks to work out, but I think everything will be a little easier as I become more familiar with the process. If I subscribe to any philosophy it's that in brewing you just have to do what you feel is right at that time. With experience you'll begin to make the right decisions, yielding better beer.