My first 2.5 gallon BIAB

I just did my first BIAB recipe today. I've been doing extract recipes for the last year and this is the first time I'm working with all grain, and it's the first time I've done a 2.5 gallon batch. I am making a Spotted Cow clone. Here is the recipe:

3 lbs 2 Row
1 lb White Wheat
.5 lb Carapils
.25 lb Flaked Corn
.25 Caramel 20L

.5 oz Brewers Gold - 45 min
1 oz Saaz - 1 min
1 tsp Irish Moss - 60 min

Kolcsh Yeast

I started by heating 4 gallons of water to 163 and then added the grain. The temperature dropped to about 150. I then wrapped the pot (5.5 gallon brewpot) in towels. I let the grains sit for 1 hour, stirring every 20 minutes. I had a hard time keeping the temp stable. I had to put it back on the burner set on low. I'm also not sure how accurate my probe thermometer is. I was surprised to see the temp drop that low after adding 5 lbs of grain.

After boiling, adding irish moss, hops, and cooling, I took a gravity reading and it was 1.043. I then pitched the yeast. The final volume was about 2.75 gallons. I think the volume is ok, since I figure I'll put this in a secondary and lose at least another quarter of a gallon.

I just wanted to share this with people and see what they thought of my numbers. I did the calculation for efficiency and it came out to 65%. I know that's not the greatest, but it's my first attempt. I think it may have been low due to the low mash temp.

Any thoughts from anyone?

Thanks
Todd

How were your grains crushed? One way to improve and is a benefit to biab is that you can have finer grains. Don't need to worry about a stuck mash.

I think your mash temp was fine and not the cause of low efficieny. Like Bucks-04 said, the crush is the key and finer is better. I use a grain mill and grind mine quite fine and get efficiency in the upper 70's to low 80's. Also, squeeze the heck out of the grain bag when you take it out of the kettle to get out all the sugars.

+1 squeeze the bag. No danger of tanins, and it greatly improves efficiency. I also have a second pot that I heat to 170 to sparge the grains, though if you temporarily remove the grains you could probably use just one pot.

Also, for temperature stability, if you can put it in your oven at lowest temp that will help. The temp difference between 180 degree air and 153 degree wort is much less than 80 degree air and 153 degree wort.

I crushed my grains using the mill at my LHBS. I ran them through one time.

My oven only goes to 170, so I didn't think I could put it in there, but it's a good point about the air temp.

I also didn't think you were supposed to squeeze the bag, that it would release tanins.

If your ph is way off,then you may extract tannins.

When doing biab you can squeeze the bag. Or if you don't feel comfortable you can let it hang above the pot for a while. If you don't feel comfortable YouTube it or listen to a podcast on basicbrewing.com. I think if you go to the radio section and go to 2009 ( I think) they actually have 2 podcasts.

I personnaly don't feel like your pH level will increase your efficiency up to 80% I think by being able to control your temps, how long the mash is and your grains should be you first concerns.

I'm not a believer in super fine crush for BIAB. If you create flour you will have clumps of grain which is not a good thing. Squeezing the grain bag will increase your efficiency as you are leaving a lot of wort sitting in the bag with the grain. So the right crush, holding temps & water chemistry all play a part in efficiency. btw - 65% for your first attempt is not awful at all. Keep working it!

I did let the bag drain into another pot and added that back to the boil kettle. I'll try to squeeze it next time. Do I need to increase my temperature on the mash, will that help? Like I said, it was around 150, but I can't tell how accurate my thermometer is. Any suggestions on a new one?

Samc, thanks for the vote of confidence on the 65%. I didn't think it was great, but also didn't think it was that bad for my first attempt.

150F is ok, making sure your temps are correct as you know is important (since your 150F could have been 140F). I use a CDN Pro Accurate that Amazon has for $11+, it is accurate and I just verify my RTD/PID temps with it - can't go wrong and will do the job unless you want to spend $90 on the ThermaPen which everyone seems to love.