Mini-Bag: Final Volume Question, Strike Temp & Boil Time

For those who like to brew BIAB just using their stovetop.
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LI Mike D
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Mini-Bag: Final Volume Question, Strike Temp & Boil Time

Post by LI Mike D » 1 year ago

A few quick questions. I made the Amarillio APA yesterday scaled to a 1 gal final volume (including trub). I brew in a 3 gal Target Tamale pot. The calculator scaled down to 9+ liters, but my pot maxes out at 8 liters/quarts. So I ended up 1 liter/quart short.

1. The recipe calls for a 90 minute boil but hops don't get added until 30 minutes in to the boil? what is the benefit of a 90 minute boil without hops for the first 30 minutes? Why not just do a 60 Minute boil with less water, wouldn't that yield a better mash? 9 liters for 1200 grams of grain


2. While I should have known I would end up 1 liter/quart short of 1 gal for the primary, I added fresh water to the primary lowering my SG from 1.055 to 1,k054 which I can certainly live with (target from recipe was 1.058) . Is there a danger to adding tap water to the primary when my boil comes up short?


3. Talk to me about mash temps. I've been reading that a multi=step mash gives the brewer more control over the starch conversions for better efficiency as well as desired taste for the style. Is the single temp infusion simply for convenience or does it have something to do with mashing at full volume. Seems it wouldn't be difficult to do a two step mash, first rest win the low 140'sF and then a second rest at 155-160F to properly mash both Alpha and Beta enzymes. Am I over thinking this or missing something (being fairly new to all grain home brewing).


Thanks


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Post by Scott » 1 year ago

LI Mike D,

Some Quick answers, and likely will not cover everything.

We like to mash for 90 minutes and also boil for 90. A 90 minute boil will have more evaporation so you will have to add water at the end. The BIABacus has a section to record the water added to the fermenter. Pat, or PistolPatch had some great info to explain the process (think it was from last spring). Sorry but I can't look for it right now...

Most of my beers are 2-step or 3-step, step mashes. (Brewing with Weyermann Bohemian floor malted Pilsner Malt, not quite fully modified, so supposedly can benefit from a third step / protein rest. I normally do the Hoch Kurz (German) mash schedule for lagers.

I had a couple brews (Pilsners) last summer using Great Western Pilsner Malt, and one I got messed up and just did a single infusion mash. The other did my regular Hoch Kurz mash that had mash spend time in both Alpha and Beta Amalyse. Anyhow, the step mash wound up WAY BETTER! Now that malt is likely not quite as good in my opinion as the German Malt... But the one with the step mash was way better. You'll want to know why... The single step mash - at least with this mash - had an extra bitterness from the malt (I believe) that some thought came from hops. Just wasn't as smooth as the step mash. Now this said, I sometimes use single infusion mashes (most of my ales have been single infusion...).

Anyhow, hope this helps.

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Post by LI Mike D » 1 year ago

^^^ That did help, thank you. Perfect


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Post by Brew4me » 1 year ago

In addition to what Scott stated here are some other thoughts...
1. The recipe calls for a 90 minute boil but hops don't get added until 30 minutes in to the boil? what is the benefit of a 90 minute boil without hops for the first 30 minutes? Why not just do a 60 Minute boil with less water, wouldn't that yield a better mash? 9 liters for 1200 grams of grain

The boil time of 90 vs 60 minutes is associated with the malt - nothing to do with when hops are to be added. We are trying to get the most sugar out of the grains and 90 minutes ensures you getting the most possible. Also 90 minute boils help reduce DMS in the beer – usually more an issue with lagers using pale malts, the roasted malts from processing create less DMS. DMS is a sulfur compound (Dimethyl Sulfide). Search the site – there is a bit of info on 90 minute boils with additional reasons for going with 90 minutes. Here is a short article on boiling I got of this site somewhere… :scratch: http://bavarianbrewerytech.com/news/boilhops.htm

2. While I should have known I would end up 1 liter/quart short of 1 gal for the primary, I added fresh water to the primary lowering my SG from 1.055 to 1,k054 which I can certainly live with (target from recipe was 1.058) . Is there a danger to adding tap water to the primary when my boil comes up short?

You are likely alright with the added water – really depends on how you added it. There are things to watch out for such as sterilization – you just boiled and therefore sterilized in the boil now you’re adding tap water(?). BIABacus has a section W “Full-Volume Variations – FVV” that shows a couple of methods to add water – in a sparge, before boil, during boil, added to fermentor. I have used the FVV in the past- both adding before boil and in fermentor – there are always trade-offs when doing so but it works – search the site for FVV especially the PistolPatch - he has a nice post where he walks through the trade offs of FVV.
You may also want to run some test boils with your kettle to understand your evaporation rate – for example after a couple of brews I realized my evap rate was not the default and hence adjusted in section X “BIABacus Default Adjustments” evaporation rate to 3 liters/hour. (you should do this whenever you change to a new kettle)

3. Talk to me about mash temps. I've been reading that a multi=step mash gives the brewer more control over the starch conversions for better efficiency as well as desired taste for the style. Is the single temp infusion simply for convenience or does it have something to do with mashing at full volume. Seems it wouldn't be difficult to do a two step mash, first rest win the low 140'sF and then a second rest at 155-160F to properly mash both Alpha and Beta enzymes. Am I over thinking this or missing something (being fairly new to all grain home brewing).

Most malt today are well modified and people believe that step mashing is not as necessary as the old days. In the malting process the grain is allowed to germinate in which chemical changes occur that change the structure and composition of the kernels. These changes let us get to the starches (sugar) more easily – this process is called modification. Modification breaks down the grain kernel’s structure to a softer texture where the sugars are the most accessible. Under-modified still has starch in the grains and in over-modified the sugars already started to be consumed in the malting process. The less modified malts benefit from a protein rest to breakdown proteins and release the starches. You can check the Malt Analysis Sheets if you are not sure how well modified the malt is. Here is a site to learn about the sheets https://www.morebeer.com/brewingtechniq ... oonan.html

Pete
Last edited by Brew4me on 30 Oct 2016, 08:25, edited 1 time in total.


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Post by Zoner » 1 year ago

LI Mike D, True BIAB here most often uses a 90 min boil after a 90 min mash. The volume of water used in the BIAB mash of your grain weight is reduced in the 90 min boil to achieve the volume that fits the target OG of the recipe. If you used less water, the BIABacus would tell you to use a different amount of grain - it is a balancing act for what fits in your kettle and getting to desired liquid volumes and OG at the end of the process. There are occasions where water can be added; the BIABacus has sections for just that. The water that gets added after the wort has boiled should also have been boiled, it is best if not fresh from the tap. You put the batch at risk for lack of a 5min boil of tap water?
The story on step mashing as Scott & Brew4me wrote above is that at our scale, home brewers using modern, well modified malts crushed to the size we need, generally do not require step mashing. If you make the same recipe over and over, it presents an opportunity to investigate for impact. You can do step mashing if you like, and if you find that it helps a particular recipe make a better beer, please let us all know. I did it once, and if I someday repeat that recipe, I'll think about changing it, but I now target one temp for 90 min mash for making ales.
Part of the beauty of home brewing (especially BIAB) is that we do not have to do what commercial scale brewers do with their scale and equipment. It does not have to be that complicated to make good beer. :thumbs:


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Post by Scott » 1 year ago

With lagers, and In Particular - Pilsners - a step mash has been quite helpful and as far as I'm concerned...highly recommended. And at least for my setup, a step mash is easy to do.

3-step mash starts to become a bit of a pain... Most malts are fully modified but the Bohemian floor malted is not fully modified... Wonder if I can skip the protein rest...regardless of the malt not being fully modified? Seems like at least on one of my brews I did...and the beer was still good. Limited opportunity for side-by-side tests. But no doubt about this malt not being fully modified. But some other fully modified malts used with Pilsner (Great Western Pilsner Malt, as noted above) was definitely better with a step mash.

Have never done step mash for an ale...not with the malts I've used.

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