adjusting starting gravity - extract

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adjusting starting gravity - extract

Post by waiter23 » Tue Apr 24, 2007 7:00 pm

Looking for a few tips on adjusting specific gravity. If I make about 2 gal. of wort and mix it w/ 3 gal. of water to make 5 gal. and find that my hydrometer reading is to high/low for the style of beer i'm making what can I do to adjust it before fermintation. Add corn sugar(low) or water(high)??? How much??? Any input would be appreciated. Thanks

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Adjusting Gravity

Post by slothrob » Tue Apr 24, 2007 8:19 pm

Ideally, you want to check the gravity before the boil, know your evaporation, and make any additions before the end of the boil. But that's not crucial.

To increase the gravity, add DME. Adding 1# of DME to 5 gallons of water will add about 8.8 points to your gravity. Adding this at the end of the boil will sterilize it, but I've heard of people adding it directly to the fermentor or adding it to a smaller amount of water to pasteurize it.

To decrease the gravity you can add water that has been boiled and cooled. To determine how much water to add:

Total points expected = Expected gravity x Expected final volume

Total points actual = Measured gravity x Volume when measured

Final volume = Total points measured / Total points expected

You can use similar math to calculate how much DME to add, if you subtract the Total points measured from the Total points expected. The DME will add 44 total points per pound, so divide the number of Total points you fell short by 44 and you'll get the pounds of DME you need to add.
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Post by MrDanders » Wed Apr 25, 2007 8:26 pm

I have an easy way to hit the target gravity: If you are boiling something less than the full 5 gallons, say 3 gallons, then only pour one gallon of fresh cold water into the fermenter first, not the full 2. When the wort is appropriately cooled, dump it in to the fermenter -- now holding about 4 gallons -- and take a gravity check (Always sterilize the hydrometer!). Your Gravity should be too high at this point (from the target, that is). Slowly add more fresh water and continue to read the hydro. Sometimes you'll have to stop below the 5-gallon mark; other times you'll have to have extra fresh bottled water on hand to go above the 5 gallon mark to hit the OG.

In either case, you need not fret over hitting the target exactly. Relax!

"Beer, beer, so amber and so clear. 'Tis not as sweet as woman's lips, but always more sincere..."

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