• Welcome to the new forum! We upgraded our forum software with a host of new boards, capabilities and features. It is also more secure.
    Jump in and join the conversation! You can learn more about the upgrade and new features here.

Low Original Gravity (2nd time)

jaybird789

Apprentice
Joined
May 28, 2012
Messages
14
Reaction score
0
I need help from all the beer buddies out there. I'm new to all grain. I have made 2 batches and my OG has been well off the mark. I have my equipment profiles in Beersmith and I always calculate a final 5 gal batch.

Today I tried a Celebration clone as follows:

12 lbs 3 oz Pale Malt (2row)
8.6 oz Carmel/Crystal (60)
8.2 oz Carmel/Crystal (120)
5.7 Cara-pils/Dexedrine
4.3 Chocolate Malt

I mashed in at 169 (19 qt of water calculated by BS) and hit my step temp of 152. (I added PH balance in my mash water) I did a complete stir and add of grains, placed the lid and set for 60 Min's.

I did my first runnings and added it back in the tun then Fly sparged.

(5.22gal calculated by BS) at 168. I made sure I sparged for at least a half hour but didn't re mix the grains (I've been told this will mess up the grain bed).

The initial mash was beauty and very sweet! I did a 60 min boil with a total water volume of 7.89 gal adjusted for my equipment profile.

Am I using too much water or not enough grain? Very frustrating as I measured my tun and trub loss for my equipment profile. (10 gal coolers). Sorry so long but I'm dying to make my beer hit the right numbers. Any help is appreciated. Frustrated  :-X
 
Are you correcting for temperature?  I'm guessing not, because you reading makes more sense if you took it at mash temp.
 
Ok.  So, either your mash and lauter are totally messed up or you measurement is. That's less than 50 %  efficiency.  Simply draining the mlt should get you 55% or so.

I would start by checking your hydrometer and thermometer for calibration.

Then always be sure to cool you hydrometer sample to below 100f.  Correction for temperature shoveler that are junk.

I would also carefully check your volume calibration. I don't think that's the problem here, but always good to do when things don't make sense.

Then for your next batch try batch sparging. Take hydrometer, temp, and volume measurements of each set of runnings.

Was you wort thick and strongly sweet? Or was it lightly sweet? There is a big flavor difference between a 60 and a 36 wort.
 
Sparge for at least an hour and increase sparge water temperature to 170-175 for starters.  30 minute sparge is way too short.....I found that an hour minimum works wonders.  I've been getting 77-84 percent brewhouse eff and about 90% mash since I changed those two parameters.

What was your mash efficiency?  Did you take a reading once sparge was complete?  What was your pre boil volume?

Mark
 
Tom: Thanks, my first runnings were amazing! The right SRM very sweet and tasted fantastic. I ran 16 cups back in to clear the grain bed and then went to my sparge. I did forget to place a tube long enough to reach the bottom of my brew pot so it did splash but that should not have an effect on gravity (just guessing). Since I made my profile in BS, and calculated for a full five gallons, it did say to add water (after sparge) to achieve final volume of 5.75 gal. I had to add 8 cups of water to do that. Would that have set it off? I'll double check my boil pot for trub loss in my equipment profile. It is a 12 gallon kettle with a bent copper tube manafold. Yesterday after I used my wort chiller, There was 16 cups left before the siphoning effect ended. I easily got six gallons of wort. I stopped just at the crest of the carboy to allow for head space. One other question? I did use a plate to "press" down my grains for wort after my sparge. (I did it four times) is that a bad idea? Sorry for the long post but thanks for the help. Jay
 
Mark, I will try the longer sparge and increase temp next time. I'm using the calculations from Beer Smith so I thought that was what it was designed to do. It calculates my brehouse efficincy at 72% so I must have some profile issues. Not sure how to get mash efficiency. Is that in the profile? I didn't take a reading directly after the sparge so I'll be sure to do that next time. Pre Boil with my equipment and fermenter loss to make a final bottling batch of 5.13 gal was 7.89 gal. (batch size was 5.75 gal) but I know I got more because I filled my 6 gal carboy almost to the top. Looks like I need to join a club! Thank's for the time. Jay

merfizle said:
Sparge for at least an hour and increase sparge water temperature to 170-175 for starters.  30 minute sparge is way too short.....I found that an hour minimum works wonders.  I've been getting 77-84 percent brewhouse eff and about 90% mash since I changed those two parameters.

What was your mash efficiency?  Did you take a reading once sparge was complete?  What was your pre boil volume?

Mark
 
This may be a silly question but why sparge for an hour and how do you make it take so long?  Do you open the ball valve to a miniscule degree and just let it run slowly?  Why such a slow sparge rate?
 
Not a stupid question at all.  It helps with efficiency....my pro brewer friends say to always sparge 60-90 minutes.  30 minutes of sparging will leave too much sugar behind.

Yep, just have it trickle out.  I do some simple math using my expected preboil volume to determine how much volume I should have starting at 20 minutes.  I'm I'm low, increase flow a tad....otherwise slow it down a bit.

Mark
 
jaybird789 said:
Tom: Thanks, my first runnings were amazing! The right SRM very sweet and tasted fantastic. I ran 16 cups back in to clear the grain bed and then went to my sparge. I did forget to place a tube long enough to reach the bottom of my brew pot so it did splash but that should not have an effect on gravity (just guessing). Since I made my profile in BS, and calculated for a full five gallons, it did say to add water (after sparge) to achieve final volume of 5.75 gal. I had to add 8 cups of water to do that. Would that have set it off? I'll double check my boil pot for trub loss in my equipment profile. It is a 12 gallon kettle with a bent copper tube manafold. Yesterday after I used my wort chiller, There was 16 cups left before the siphoning effect ended. I easily got six gallons of wort. I stopped just at the crest of the carboy to allow for head space. One other question? I did use a plate to "press" down my grains for wort after my sparge. (I did it four times) is that a bad idea? Sorry for the long post but thanks for the help. Jay

I'm guessing you didn't take a gravity reading of your first runnings?  Since your first runnings aren't diluted by your sparge water, it is a good measure of you CONVERSION efficiency.    See here:

http://braukaiser.com/wiki/index.php?title=Troubleshooting_Brewhouse_Efficiency

I don't fly sparge, so I can't really help there.  Everything I've read agrees with what Mark says, though....90 minutes. 

There's nothing wrong with squeezing the grain, but its some work, for very little return....I'd rather use more grain and water and not bother.

------------------------------------

The following is a bit off topic, but its in response to your statement: "it did say to add water (after sparge) to achieve final volume of 5.75 gal."

I NEVER add water to achieve a specific volume of wort.  I add water or DME to adjust my GRAVITY.  Actually, I adjust my gravity POINTS (total sugars).  If my volume is low then I will add water + DME to get volume and gravity to the expected level.  But, if my volume is HIGH, then I will only add DME to get my points correct and then boil longer to get to my desired post-boil gravity. 

In order to make the beer you planned on making, its your post-boil gravity that matters.  Not your pre-boil.  Your preboil gravity is only a stop along the way.  Don't get me wrong, you can't fix a volume that is off by double or something....but, if you have an extra 1/2 gallon, another 30 minutes of gentle boiling won't make much difference in the final beer. 

So, my procedure is this:

Say my targets are the following:

preboil: 1.050 @ 8.0 gallons
postboil: 1.062 @ 6.5 gallons
90 minute boil @ 1 gallon / hour.


1.  Ensure that I have the correct amount of sugar pre-boil.  (SG - 1)*1000 * volume = points.  Add DME to adjust points upwards as needed.  If total points is too high, then remove the appropriate amount of wort, to get the points down to the correct number.

Instead of my planned values I get: 1.050 @ 7.75 gallons

(1.050 - 1)*1000 * 7.75 = (0.050)*1000 * 7.75 = 50 points/gallon * 7.75 gallons = 387.5 points

I should have gotten 50 * 8 = 400 points.  So, I need 13.5 more points.  DME = 46 points per pound (per gallon).  13/5/46 = 0.29 lbs = 4.75 oz.

Now I have 400 points of sugar, but only 7.75 gallons of wort.  1.052 @ 7.75 gallons

2.  Ensure that I have enough volume to boil-off for my desired time (90 minutes if using pilsner malt, 60 minutes otherwise...@ 1 gallon per hour boil-off).  I add water if its too low.

Add 1/4 gallon of water.  1.050 @ 8.0 gallons.

3.  Calculate my boil-off duration based on 1 gallon per hour.  If I have too much wort, then I just plan to boil down until I hit my planned pre-boil volume. 

Suppose instead I'd had: 1.047 @ 8.5 gallons = 400 points.  my points are right, but I have too much water.  I need to boil-off 1/2 gallon extra.  That takes me 30 minutes.  I have a sight gage on my kettle, and I can simply boil down until I hit the 8.0 gallon mark.

Suppose in step 1, I'd had: 1.055 @ 8.5 gallons = 467.5 points.  Now I have too much sugar, and too much water.  I need to remove 67.5points.  67.5/55 = 1.20 gallons.  So, I remove 1.2 gallon of wort (and set aside, but keep just in case I need it later).  Now I have my 400 points, but I only have 8.5 - 1.2 =7.3 gallons of wort.  I need to add 0.7 gallons of water. 


I guess that's long way to say...don't just blindly follow instructions like "add water to achieve a volume of XXX".  You can, and it will make beer, but it will always be a different beer than your recipe describes.  The above procedure, is hard to explain in words...but, easy to do on paper.  Most of the time I can do it in my head...but, generally use paper anyway to avoid the "Doh!" moments.



 
Thank you all for your help. It's frustrating to do all the work according to the steps and NOT get the beer you want. I did test my hydrometer at 60 degrees and it was spot on at 1.000. You all have given me food for thought. One clairification. Mark, you mentioned longer sparging leaves less sugar. Isn't my problem that my SP is low and some how I'm loosing sugar? Please let me know if I'm getting that incorrect.

I don't have any brew clubs in town and most people you meet in the brew shop arn't interested in helping new brewers. You all have helped alot! Any further pointers are greatly welcomed.

Jay :)
 
Here's my $.02 on the process.

I mash in a bag and dunk sparge (the bag in sparge water) for 10 minutes with no further grain "washing". I get 70+% efficiency without much of an effort.
 
Jay, I missed that you were adding top off water.  This tells me that you are not sparging with enough water.  You should get your entire preboil volume from your mash water and sparge water.  Top off water is "wasted" in that you aren't using it to rinse your grains.

Mark
 
I am going to hi-jack the thread again.  I currently fly sparge and I try and set the flow on the sparge water as it comes in to match the flow on the MLT heading out.  I shoot for keeping a level amount of water above the grain bed.  But if you sparge over a 90 minute window are you not essentially increasing the mash time? 
 
Humble Brewer said:
I am going to hi-jack the thread again.  I currently fly sparge and I try and set the flow on the sparge water as it comes in to match the flow on the MLT heading out.  I shoot for keeping a level amount of water above the grain bed.  But if you sparge over a 90 minute window are you not essentially increasing the mash time?

That's possible if under modified malt is used.  In my experience most of the conversion is done in the first 15-20 minutes.
 
Things off the top of my head that could result in a low O.G.

Bad grind.  Incomplete conversion.  Not mashing out.  Sparge water not hot.  Sparging too fast.

After the mash passes an iodine test I remove a third, bring it to a full boil, and add it back in.  This raises the temp to 160 or so, and my sparge water is closer to 170. I recirculate for a half hour, running at a mere trickle. It then takes most of an hour to run the fly sparge, again at a trickle, collecting a total of about seven gallons.  My efficiency runs between 70 and 85 percent.
 
Sorry to hijack.
merfizle said:
Jay, I missed that you were adding top off water.  This tells me that you are not sparging with enough water.  You should get your entire preboil volume from your mash water and sparge water.  Top off water is "wasted" in that you aren't using it to rinse your grains.

Mark

Typically you should sparge with the amount you want to finish with. 5 gal batch = 5 gallons sparge water. 
Sparging rate should be about 1 ltr a min.

Also read this, it cant hurt. 
http://www.beersmith.com/forum/index.php/topic,5140.0.html
 
Humble Brewer said:
But if you sparge over a 90 minute window are you not essentially increasing the mash time?
No. Because the sparge water is set to around 168F which is above the temp the alpha and beta enzymes like, thereby shutting off the enzyme activity and only rinsing the grist.

Cheers
Preston
 
Back
Top