help!! consistently low OG

[BrewerAdam]

I understand where our differences are.I failed to recognize the desire was to know brewhouse eff. My initial reply was in regards to the original post. The numbers are off for each brew. It has been established that everything but thermometers seem to be accurate. So that leaves us with a few options. Temp of mash being one,i.e. wort with higher/lower attenuation. This is where I suggested to determine how well the extraction eff. was.(possibly help determine if problem is a bi-product of the mash) Next option is over sparging and or the evap rate during boil. The OP is using a recipe with assumed 75% eff. Without knowing what OP's personal brewhouse eff is, we cannot assume they have the same eff. I agree with you Palmer's calculations are excellent. For the OP to establish their eff. and rule out any possible system issues is what is needed to therefore scale the recipe to meet the recipe numbers.

Again, Im not trying to be an ass, but what exactly does your "extraction eff." tell us? Going back to the original post and using your calculation for "Extraction Efficiency" we do the following calculations:

37/45 = 82%
55/60 = 91%
42/48 = 87%

To me, these numbers only tell the OP that he is not getting the yield that he was shooting for (which he knows because he posted here)? How does this help him in fixing his problem?

[megDC]

37/45 = 82%
55/60 = 91%
42/48 = 87%

To me, these numbers only tell the OP that he is not getting the yield that he was shooting for (which he knows because he posted here)? How does this help him in fixing his problem?

SHE!

And my efficiencies were well below 82%, 91% and 87%. I dream of getting 70%. The first three batches had the efficiency of 50-55%. I am definitely screwing up something.

[cheezycow]

Again, Im not trying to be an ass

noted


They help us determine if the mash was true culprit.....If those numbers are off it could be the crush or the temp at which the mash was conducted. thus tells us our grain potential. The OG will differ whether the mash was conducted at 149 vs 156. Granted this will only be a minor change but a change that will effect her OG.How does the fix her problem....Well for starters it helps narrow down the possibility of the problem being in the mash. It was already asked what the crush was, and she is comfortable with all equipment but her thermometer being possibly inaccurate. Honestly the crush size stated is fine. The numbers she stated are her OG, as I said before I failed to recognize that she is trying to determine her overall(brewhouse) efficiency. The numbers I talk are the Pre-boil gravity(which were not stated). Obviously the lack of wort is coming from either her mash(extract eff), oversparge (over-diluted wort), or poss. her evaporation rate(total wort not reducing enough).


To MegDC... using Palmer's calculations will help you determine your brewhouse efficiency. Also get that thermometer calibrated for your next brew...target that mash temp...make sure you stir alot to reduce dough-balls(which could reduce your yield)...And take your preboil gravity. When you figure what your brewhouse eff is then you need to compare the recipe's efficiency with your actual efficiency and scale your recipe so the numbers will match

I personally use beersmith and think its great, as long as your equipment settings are accurate.


oh for the record I'm also not trying to be an ass...just trying to help

[kevindalyus]

Hey, I just wanted to let you know I had this same exact issue a year ago...there are 5 pages of responses, but basically everyone says the same thing: it's the crush.
And oddly enough, I went with a finer crush and hit my numbers every time.
That being said, Tasty also chimed in with some excellent advice:

If you don't care if your beer is under/over hopped or your ABV is 5.5/6.0% then yes, skip the preboil gravity. You'll never get control of your process and you'll struggle to clone commercial beer recipes or make the same recipe twice. 2010 North American two-row is all over the board in terms of extract potential and your LHBS has better things to do than tell you what they are selling you.

If you want a repeatable process where you control the outcome not the dude at the LHBS, the maltser, or the farmer in Canada, then always take a preboil gravity. Your brewing software should tell you what it should be given your efficiency once you get that established for your grist, grist to water ratio, mash Ph, etc.. If you're higher than the recipe calls for you can add water until you get down to the target preboil while adjusting the hops for the higher volume of wort. If you're under the target preboil gravity, either boil until you get to the target preboil and adjust the hops for the lower volume of wort or add DME/LME until you get your target gravity. Don't be a victim.

Okay? Got that DME and a way to chill a wort sample?

Tasty

So there you have it: crush and a preboil gravity reading
If you're interested, the whole link is here: viewtopic.php?f=2&t=24699

good luck

[megDC]

Thank you for that forum link. I am going to read thru it now.

I did brew yesterday and here is what happened.

I crushed my grains the night before, twice thru my mill. My boyfriend was finally home this weekend to help since deer season is over! (previously I opened by ball valve from my HLT to run into my mash tun because I did not want to lift it to put the water in. I think I lost a lot of heat in that process, and that is a main reason I lost efficiency, low mash temp).

My boyfriend was able to dump the water directly into the mash tun, added the grains, and got my mash temp at 152 F. The water/grain ratio I used was 1.5 qt/lb. At 60 mins, the temp dropped to 150F. I had the sparge water at 170F, vorlaufed about 1.5 gallons of wort, and then collected 6.5 gallons of wort into my boil kettle. I did check the pre boil gravity, and it was 1.035, I was going for 1.038. I added 4 ounce of DME, which seemed to bring it up to my gravity goal. I checked some calcs this morning, and I should have added 7 ounces DME (internet down so could not get calculations yesterday).

Boiled for 90 minutes, down to 5.25 gallons but my gravity was 1.043, off from my estimated gravity of 1.048.

I have calibrated my thermometers and refractometer. I heard that fly sparging with a stainless steel braid could make a difference. It is what I do. What do you think??

Hey, its better then my last couple brew days, but I am still fucking something up. I am tired of getting crappy numbers and worse, crappy beer.

[Cliff]

You are asking people to shoot in the dark
The crush the water the Ph Yadda yadda Yadda on and on the guessing goes..

It's be really helpful for you to describe your process,
what Ph is your water when you start out,
what's yer crush or who is doing it,
what grains are you using,
how many pounds per how many gallons of water,
what is the water to grain ratio in your MT,
what temperatures are you mashing at,
for how long are you at these temps,
What is your mashout like?
what is your sparge routine

Everything matters.

[kevindalyus]

Hi there, I read your brew day and one thing jumped out at me: what is your evaporation rate?
I don't want to throw a bunch more numbers at you, but that really is an important one. I understand that you boiled 90 minutes and went from 6.50 gal to 5.25 gal, so if your preboil gravity was pretty close to being on, then your final (original) gravity should be on.
Are you using a brewing software? That should really help you with your numbers.
As far as sparge method, again, as long as you hit your numbers, it really doesn't matter. I tried fly sparging and found it to not work well for me (rectangular igloo with ss braid). I found it much easier to do my first running, then do a batch sparge. I use heat proof tubing and insert it into the grist and run sparge water through the grains (and let sit for 10 minutes). I do that as many times as need to get to preboil volume.
But again, if your preboil numbers are on, I can't really understand why your original gravity is off. If you really want to hit that number, you really need to make sure your evaporation rate is calculating properly. Obviously this will affect the amount and timing of hops.
I could tell you to just keep boiling down to reach your numbers (keep doing gravity checks using something to ice down the sample), but this is going to affect your final ibu's....it's tricky.
I would suggest you get brewing software if you don't already, and make sure you have dme on hand (we all do) so that you can stick to your boil/hop schedule.

[spiderwrangler]

It may have been said, but what size/shape mash tun do you use? What is your size and shape of your SS braid? I brewed with a friend using a 10gal igloo with a straight braid (mine is circular), and it seemed like it was causing channeling for him where the end of the braid lifted off the floor of the cooler. It didn't really matter for him since he was batching, but since you are fly sparging, if you have big channeling issues, you may be leaving a lot behind in the mashtun. Unless you are philosophically opposed to it, you could try a batch sparge and see if that brings your numbers up. Fly may have a higher potential efficiency than batch, but only if everything is perfect.