My 1st BIAB Log

[seminaryfleming]

Good Afternoon!

Two days ago I completed my very first BIAB brew.

It was also my 3rd brew, the first two being Northern Brewer kits.

I'm not sure how well it went, so I want comments and critiques on what I did, and where I may have gone wrong. So here's my log:

Sunday I went by Perfect Brewing Supply to check out the closest home-brew store to my house. I had a great time. I had come with a recipe for Rob's Oatmeal Stout. Much to my surprise I had it written down in an understandable format and they set to work putting the grains together. While I was waiting I sampled a Kölsch that they had on tap. That convinced me to try a gallon batch of that. So I walked out with two recipes worth of grain, hops, and yeast as well as a new 5 Gallon kettle.

Monday I actually brewed. The Kölsch recipe is as follows:

1lb Pilsen Malt
.7lb White Wheat Malt
.05lb Caramel Malt 10L
.2oz Hallertau Hops 4.6%AA @60min
.1oz Hallertau Hops 4.6%AA @15min
.1oz Hallertau Hops 4.6%AA @1min
WYeast WY2565 in a smackpack

expected OG: 1.045

I used Simple BIAB Calculator with guestimates on my water loss in order to figure out what to do. I brought 1.5 Gal water to 158F and added the grains. I stirred, put my digital thermometer probe back in and insulated the pot. It stayed at 154F for the entire hour. Towards the end of the hour I started heating another .75 Gal in another pot to 170F. I squeezed out the grain bag and transferred it to the sparge water for 10 minutes. Then I lifted it out again and squeezed it a bit.

At this point I had to take a break to put kids to bed. I came back and started the boil. I never got much foam, and really didn't get a hot break I could see. After about 15 minutes of boiling I realized my WAG on evaporation loss was waaaaay off. I had input 1 gal/hr. I think I'm actually closer to .5 gal/hr. Oh well. I decided to let the wort boil for another 15 minutes before I added the hops.

After 30 minutes of boiling I added the first hops. I then set my timer for 45 minutes and waited. When it went off I saw that my boil off was going to be nowhere near the 1.25 Gal I wanted to end up with in 15 minutes, so I let it go. In the end I had let it go another 30 minutes. (We're now 1:45 into the boil and its getting late) I added the 15 minute hops and set my timer. Then the 1min hops and cut the flame.

Chilling took way too long. The new pot filled my sink entirely, so I couldn't get a good amount of water around it to chill it with. I'll have to come up with another solution. Anyway, I got it down to 70 and took a hydrometer reading at 1.036. That was disappointing. I'm .09 off what I expected.

Anyway, I dumped the wort into my sanitized fermenter. At that point I realized just how much nasty trubness there was, so I dumped it back into the kettle and re-cleaned and sanitized the fermenter while I let the wort settle. Then I siphoned it off. I still got some hops and other solids, but not nearly as much. I aerated and pitched the smackpack that was nicely bloated by this point.

I ended up with 1.25 Gal in my fermenter which is right where I wanted it as I figure I'll lose another .25 gal to the yeast cake/trub.

So my questions are:

1) Why was my OG so low?
2) Will that 2HR boil change anything?
3) The wort was significantly darker than I expected. the Kölsch in the LHBS was really quite light almost yellowish while mine was definitely a darker tan color. Will this change in fermenting?

Thanks!

 

[porterpounder]

1) The OG is likely low due to poor efficiency of your system. Double-crush the grain next time if you didn't and check the mash pH. Strips work fine. Not that it will improve your efficiency much, but the sparge step seems a bit tedious. Just mash with all your water and squeeze the bag a bit if you feel you need to.

2) The boil may darken the beer up slightly, but with that first hop addition, it's going to be a bit more bitter than you expected. With 4.6% AA hops, though, it shouldn't be excessive.
3) The darkness was likely a result of the longer boil, or the 10L malt wasn't 10 L. In the future for Kolsch try some light munich instead of caramel malt.
Some fermentations actually darken the beer up slightly, but I've never seen it get lighter.

 

[jekeane]

First thing first you need to figure out your actual volumes in your pots and make yourself an accurate dip stick.

What size kettle are you using? I'm assuming it is quite small if you needed to dunk sparge. If it's not and you can do a full volume mash there is no appreciable benefit to dunk sparging that I know of.

I use a 3.25 gallon pot and do full volume mash 2 gallon batches on the stove. If the gravity is above 1.060 then I may need to dunk/pour over sparge.

A 120 minute boil will change color a bit. The major affect extending boil times would have is if you extended boiling hops.

Your OG was low because you don't know your volumes is my assumption. OG also can suffer from a poor crush, as well as other factors.

You need to start with your volumes. Take a known quantity of water close to your pre boil volume. Boil for 60 minutes then measure accurately what's left. Subtract the preboil from the post boil then multiply by .04 (heat shrinkage) and you will have your boil of rate.

 

[seminaryfleming]

1) The OG is likely low due to poor efficiency of your system. Double-crush the grain next time if you didn't and check the mash pH. Strips work fine. Not that it will improve your efficiency much, but the sparge step seems a bit tedious. Just mash with all your water and squeeze the bag a bit if you feel you need to.

2) The boil may darken the beer up slightly, but with that first hop addition, it's going to be a bit more bitter than you expected. With 4.6% AA hops, though, it shouldn't be excessive.
3) The darkness was likely a result of the longer boil, or the 10L malt wasn't 10 L. In the future for Kolsch try some light munich instead of caramel malt.
Some fermentations actually darken the beer up slightly, but I've never seen it get lighter.

I used whatever crush the LHBS had. They kindly crushed the grain there as I don't have a mill at home.

Where can I find out more about pH and brewing?

Thanks for the options on the grains to use!

 

[seminaryfleming]

First thing first you need to figure out your actual volumes in your pots and make yourself an accurate dip stick.

What size kettle are you using? I'm assuming it is quite small if you needed to dunk sparge. If it's not and you can do a full volume mash there is no appreciable benefit to dunk sparging that I know of.

I use a 3.25 gallon pot and do full volume mash 2 gallon batches on the stove. If the gravity is above 1.060 then I may need to dunk/pour over sparge.

A 120 minute boil will change color a bit. The major affect extending boil times would have is if you extended boiling hops.

Your OG was low because you don't know your volumes is my assumption. OG also can suffer from a poor crush, as well as other factors.

You need to start with your volumes. Take a known quantity of water close to your pre boil volume. Boil for 60 minutes then measure accurately what's left. Subtract the preboil from the post boil then multiply by .04 (heat shrinkage) and you will have your boil of rate.

My current pot is 5 gallons with markings every gallon. yeah, I'll take the reading on how much is actually boiling off.

My impression on dunk sparging was that it was highly beneficial, but I can't remember where I got that impression, so it is probably wrong. You're saying I should just put the full volume of water I need for my boil in and sparge at that volume. Should I raise the temp to 170 at the end?

 

[DoctorMemory]

I used whatever crush the LHBS had. They kindly crushed the grain there as I don't have a mill at home.

Next time, explain that you're doing BIAB and ask them to run it through the mill twice. Unless they're really busy, they shouldn't have a problem doing that for you. You might also want to try full-volume mashes, and squeeze the bag over the pot after you pull it out. I usually grab the lid to the pot and the lid to my old kettle and use those to squeeze the bag while it drains into the pot.

 

[agrazela]

If I'm entering everything correctly into my brew calculator, you were expecting 88% mash efficiency. That's ambitious! But then you are at a mash ratio of ~3.4:1 (6qts:1.75lb), followed by a nice hot dunk sparge.

You got 70% mash efficiency. This is what I typically see in 5gal BIAB at a mash ratio around 2:1 with no sparge. You should have got more than you did, I agree with jekeane, your problems most likely were poor crush and not controlling your mash pH. What kind of water did you use?

As for the extended boil, I agree that will darken your wort some, but don't judge until it's in your glass. As I understand it, the 60min hops actually saw 90 (or 120?) min...but with that hop bill that's only going to increase your final IBU by 1 or 2, you're at the low end for a Kolsch anyway, and your bitterness-to-original gravity ratio is still in balance for a Kolsch. Call it a "lite Kolsch?"

You're still in good shape so far. Now the inevitable question...fermentation temperature control method?

 

[seminaryfleming]

Next time, explain that you're doing BIAB and ask them to run it through the mill twice.

Thanks for the advice. What would you recommend if I've got 3 Gallons worth of grain (7.25lb) sitting around the house that have been crushed once? It is a bit of a hike to the LHBS so I probably won't go back up for at least a month.

 

[seminaryfleming]

If I'm entering everything correctly into my brew calculator, you were expecting 88% mash efficiency. That's ambitious! But then you are at a mash ratio of ~3.4:1 (6qts:1.75lb), followed by a nice hot dunk sparge.

You got 70% mash efficiency. This is what I typically see in 5gal BIAB at a mash ratio around 2:1 with no sparge. You should have got more than you did, I agree with jekeane, your problems most likely were poor crush and not controlling your mash pH. What kind of water did you use?

Could you point me to or provide an explanation for how I calculate my efficiency? The recipe I had in hand suggested that with that grain bill shooting for 1 gallon I should expect 1.045 if I hit 72% efficiency, but I have no idea how to calculate that.

As for water I used my tap water on the understanding that if it tastes good it makes good beer. I know that may be not technically be the best, but its what I've got.

 

[doug293cz]

What were your inputs to the mash calculator? With your light grain bill, 2.25 gal of brewing water, and single sparge, your lauter efficiency should have been about 95%. 1.25 gal of post-boil wort at 1.036 puts your mash efficiency at about 72%, but your conversion efficiency at about 75%. Conversion efficiencies in excess of 95% are readily attainable, so that's were you need to focus.

Too coarse a crush can severely impact conversion, so finer crush often helps a lot. For grain that is already crushed, longer mash times can help (try 90 minutes.) Making sure you stir aggressively when doughing in (make sure you have no dough balls), and prior to pulling the bag can help a little.

Water is much more complex than "if it tastes good, it's ok for brewing." You should get some RO (reverse osmosis) water from your grocery store, and build up the water by adding gypsum, calcium chloride, and maybe some lactic acid if needed. Look at Bru'n Water to calculate how much to use based on your grain bill and style of beer. Target your mash pH at 5.4 - 5.5.

Good luck, and

Brew on

 

[jekeane]

You're saying I should just put the full volume of water I need for my boil in and sparge at that volume. Should I raise the temp to 170 at the end?

Yes to the full volume and as far as mash out I squeeze the bag like it owes me money at the end of the mash. I find that doing a mash out for 10-15 minutes between 165° and 168° helps the bag drain and I get a marginal (.002 - .004) bump in my numbers.