Dopplebock Low OG

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dallasd9

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Five days ago I brewed an All Grain Dopplebock. Everything went well from the mash through to the end of my 90 minute boil until I noticed I was about 1 gallon low on my desired wort volume (5-1/2 gal) for the fermenter. Being somewhat of a newbie I didn't take my OG reading until after I added a gallon of boiled water while still circulating. My OG was 1.056 instead of the expected 1.075. I went ahead and put it in the fermenter and today I took a reading and the SG is all the way down to 1.012 and it is still active. The FG was supposed to be 1.022.

1. Will I end up with a watered down low ABV beer now?

2. What should I have done differently?

3. Is it too late to recover from my mistakes at this point?

Thanks in advance for any advice.
 

RM-MN

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1. Yes. Will it matter all that much?
2. Crushed the grains finer so your efficiency was increased which would have gotten you a higher OG. Otherwise you could have added more grains to the mash or added malt extract to get to the expected OG.
3. Maybe. It is still possible to add sugars to the fermenter to raise the amount of alcohol produced. Simple sugars would probably ferment out completely leaving you with more alcohol and as low or lower FG. DME should contain dextrines that would limit the drying out effect of plain sugar.
 

AlexKay

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1. You’re already north of 5% ABV. It won’t be a doppelbock (maybe a bock or a marzen) but it should still taste good.
2. I’m curious as to why you ended up so low on volume. You don’t give enough details of your process to give a hint. But I always take a refractometer reading right after mash to make sure I’m in the ballpark.
3. See #1. It’ll be a perfectly good beer. Say “I meant to do that.”
 

hottpeper13

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The higher the gravity on an all grain brew the lower the efficiency. When I make 1.050 or so I get 84% when doing a 1.070-1.090 around 70% and north of 1.100, 60-65%
 
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dallasd9

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1. You’re already north of 5% ABV. It won’t be a doppelbock (maybe a bock or a marzen) but it should still taste good.
2. I’m curious as to why you ended up so low on volume. You don’t give enough details of your process to give a hint. But I always take a refractometer reading right after mash to make sure I’m in the ballpark.
3. See #1. It’ll be a perfectly good beer. Say “I meant to do that.”
I think I started with too much water after the mash (6.5 gal) then boiled off more then I anticipated.

Will the OG after mash be any different from the OG after boil while compensating for temperature each time?

Thanks for the help
 

AlexKay

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That doesn’t quite explain it: boiling reduces volume but the total sugar doesn’t change, so when you diluted post-boil you should have gotten to a reasonable OG. The problem is just not enough sugar in the pot. It may indeed be coarse-cut grain. Or, if you’re brewing in a bag, failure to squeeze. Or if not, too little sparging. Can you take us through step by step?
 
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dallasd9

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That doesn’t quite explain it: boiling reduces volume but the total sugar doesn’t change, so when you diluted post-boil you should have gotten to a reasonable OG. The problem is just not enough sugar in the pot. It may indeed be coarse-cut grain. Or, if you’re brewing in a bag, failure to squeeze. Or if not, too little sparging. Can you take us through step by step?

Grains/malts:
7 lbs of American Pale 2 row malt
7 lbs of Munich Malt
4 oz Belgian Aromatic Malt
4 oz Honey Malt
4 oz Victory Malt
3 oz Medium Crystal Malt
1 oz Black Malt

1.075 Estimated OG
1.022 Estimated FG

The grains were milled by the place that I purchased them from. Appeared to be a medium grind. Probably should have been finer.

I use the BIAB process:

1. Heated 5 gallons of water to 160F and added grains.

2. Mashed at 154F for 1 hour, circulating the entire time (return line outside of bag in the pot). Stirred the mash every 15 minutes.

3. After 1 hour mash, raised the bag into colander strainer and rinsed grain with circulating return line inside bag.

4. Squeezed bag until wort stopped draining and removed grains/colander.

5. Ended up with 4 gallons in pot so I added 1.5 gallons of water and stared boil with 5.5 gallons.

6. Boiled for 90 minutes adding hops, Irish Moss, and yeast fuel per schedule.

7. Ended boil after 90 minutes and ended up with 4.5 gallons of wort.

8. Added 1 gallon of water while circulating and chilled to 70F.

9. Transferred wort to fermentation vessel and took Hydrometer OG reading of 1.056.

10. Oxygenated wort, added yeast and closed vessel.

11. Maintained temperature at 67F for four days now.

12. Took hydrometer reading today with 1.012 SG.

Hope this helps explain my process including my mistake of not getting an OG reading prior to adding water.
 

AlexKay

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Ok, BIAB with a store crush often means low efficiency. It certainly looks low. You’ll have to figure out the correlation between amount of grain and OG for your particular system — you may just want to add more grain if you can’t convince your store to crush finer.
 
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dallasd9

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Ok, BIAB with a store crush often means low efficiency. It certainly looks low. You’ll have to figure out the correlation between amount of grain and OG for your particular system — you may just want to add more grain if you can’t convince your store to crush finer.
I think your onto the problem. I think this is justification to get my own mill 😃. Also I'm going to start doing a better job at knowing what my OG is prior to adding more water plus have DME on hand.

Thanks again for your help.
 

hotbeer

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Knowing what your SG is prior to starting your boil will always be helpful. While refractometers seem easy for some, I find that just a regular cheapo hydrometer is even easier yet. Since you haven't boiled you don't have to worry about sanitation quite as much and you can just pour the sample back to the boil kettle. And no weird corrections needed for the things that affect trying to figure out how to make it's reading comparable to a real hydrometer SG since a cheapo hydrometer is a real hydrometer.

I'll just have to think that your mash didn't get as much from the grains as you should have gotten. While some may fault BIAB, I'll just fault the grain crush and your mash and sparge procedures. The approximately 75% efficiency you should have gotten to get 1.075 OG with BIAB should be easily attainable. You'll likely have to do your own milling though.

If you don't improve your efficiency, then increase your base malts. Probably another 2lbs each of munich and pale.

I'm a little iffy about you stating that you only circulated your wort outside the bag while mashing.

Make sure you understand that when you add water, you are diluting sugars lowering the SG. And when you remove the water, usually from boil off that you are concentrating the sugars raising the SG.
 
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MikeCo

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Start with a finer grind next time if possible. Ask the shop to run the grains through the mill twice. Best to get your own mill in the long run.
Is this a 5-gallon batch, and how are you calculating starting water volume? I do full volume BIAB and start with 7 to 8 gallons for 5.5 in the fermenter depending on grain bill size. Starting with a full volume will simplify your process and a thinner mash may give you better mash efficiency.
How did you take the OG sample - it may have been lower than actual if the wort was stratified with top-off water. If the sample was significantly higher in temperature than the calibration temperature of the hydrometer, it would read low also. I say this because you mentioned you were still recirculating/chilling when you took the sample.
 
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