As part of out time saving tips post, I mentioned that cold steeping grains may help shave a little time off the brew day. This post will address how I view you can use cold steeping for saving a little time on brew day. This post will also address what advantages and disadvantages cold steeping poses in the normal brew process regardless of time saving efforts.
The origin of the cold steep arises from the potential acrid astringency that heavily roasted black malts can bring to a recipe. Malts such as black patent, carafa III, roasted barley and the like are all kilned at very high temperatures essentially burning the husk and putting a deep roast into the starches and sugars within the grain kernel. This can lead to an ashy flavor whenever you add too much of these grains to a recipe. In an effort to get a really dark beer, it is easy to over do it.
The results of a cold steep for dark roasted malts are best exemplified in the schwarzbier style. Schwarzbier at its simplest is like a black (close to opaque) looking pilsner. The greatest examples of schwarzbier have practically no roasted flavor. The black malts lend only color to the beer. How do you achieve this at home? Well, cold steeping was one technique developed to get there.
Cold steeping dark roasted malt tends to extract only color and very little flavor from black malts. The cold temp tends to not allow some of the ashy flavors to come out of the husk. There are other techniques and ingredients available to help get color without flavor (carafa special and sinimar) but cold steeping is cheap and works with the ingredients you’d have on hand for the a recipe anyway.
[On a side note: employing the cold steep for infusing coffee beans or cocoa nibs into your wort is a great technique; but a subject for another post.]
The advantages to the cold steep is the extraction of color and some malt flavors without much introduction of astringent or harsh burnt husk flavors when using black malt. A disadvantage of the cold steep process is that when you are not including these malts with other base malt at normal steeping temps you do tend to introduce a little unconverted starch into your brew. In the case of black beers this might not be a big issue. Secondly, if you are keeping the grains to less that 5-10% of the total grain bill that contribution is negligible.
How does this equate to saving time? When I used to extract brew, I used to set up my boil kettle on the burner filled with water the night before. The next day all I had to do was fire up the burner and get going. I would heat the water to ~150-160F. Kill the heat and add my steeping grains. After 30 minutes, I’d pull the grains out, refire the burner and start adding extract when I got to ~180F. Using cold steeping practiced, you can put your grain bags of crystal and roasted malts into the water the night before also. The next morning, pull out the bags and fire up the kettle. When you get to ~180F start adding your extracts and proceed as normal.
Now, I know what you are thinking. Why not just put the bags in at starting temp, then heat the water with them in there? You can do that, but I found in the past that I get slightly better flavoring and color (in terms of intensity) when either the grains sat in the 150F water for 30 minutes or were steeped overnight. I never really seemed to get full impact when I did the “ramping-to-temp” steep and heat process. The steep and heat process was how I first started brewing. After scortching the bag to the bottom of a heating kettle a couple times I went to the heat then steep practice and liked the flavor much better.
So you may not think of this as a big time savings, but when you combine this with other time savings steps that we have outlined, I think it all begins to add up.
Hopefully, this primer on cold steeping helps you out whether as another way to craft some dark beers without astringent flavors, or maybe it helps trim a few more minutes out of the brew session. Either way, let us know what you think.