What's my OG now?

[Tommyb52]

After following this recipe I found for banana bread beer,my OG was only 1.033@79 degrees. The wort went into the fermenter on Thursday midnight and the next morning had a good pressure difference in the double airlock but evened out on Saturday morning. I boiled 4 cups of water with 8 oz of maltodextrin for 7 minutes and then added it to the wort in the fermenter and now(Sunday) have a bubbling airlock. Should I take another reading (would this disturb the wort)? Or is there a way to calculate the new OG with what was added.? The ingredients below were adjusted to make a 5 gallon batch:
Banana bread ale
Size: 6.5 gal
Efficiency: 82.0%
Attenuation: 75.0%
Calories: 219.41 kcal per 12.0 fl oz

Original Gravity: 1.066 (1.000 - 1.100)
Terminal Gravity: 1.016 (1.000 - 1.100)
Color: 17.56 (0.0 - 50.0)
Alcohol: 6.48% (0.0% - 10.0%)
Bitterness: 29.0 (0.0 - 50.0)

Ingredients:
7.0 lb Wheat Malt (5.39 lbs)
6.0 lb Munich Malt (4.62lbs)
0.25 lb Cara-Pils
.25 lb Crystal 55
.25 lb Chocolate Malt
1.0 lb Oats Flaked (.77lbs)

2.0 oz Styrian (5.0%) - added during boil, boiled 60 m (1.54 oz)
.75 oz East Kent Goldings (5.0%) - added during boil, boiled 5 m (.57 oz)
1.0 ea White Labs WLP300



Notes
ADDED 3 LBS BANANA CHIPS DRYED TO MASH 45 MIN LONG 156 DEG
FLY SPARGE 170 DEG
ADD 3 LBS BANANA CHIPS TO BOIL POT

 

[IslandLizard]

an OG of 1.034 (corrected for 68°F) with 13# of grain?
That's awfully low. Did you measure correctly? Hydrometer? Calibrated?
Did you add top-up water to the fermentor?

Maltodextrin is not a fermentable, it adds mouthfeel, perceived "thickness" to your beer. That would not jump start your fermentation. Why did you add it?

It takes a good 2 weeks for beer to ferment out, plus some extra time (1-2 weeks) for conditioning. I'd say let it be for at least 2 weeks.

 

[biochemedic]

Theoretically, Maltodextrin yields ~ 40 points per pound per gallon (pppg). You could estimate that 1/2 lb would give you 20 points in 1 gal, so divided by 5 gal, you should have added 4 gravity points to your batch.

Any idea as to why your OG was so far off from your recipe?

 

[Tommyb52]

I added about 3 to 3.5 gallons of water to top off the fermentor bucket to get 5 gallons. I don't know how to adjust the hydrometer. To test,I just put it in plain water@ room temp and got 1.00 .(this is a hydrometer bought at a pet store for fish) I added the maltodextrin because I read that its basically a sugar that wouldn't affect the flavor. As I stated above,the amounts were reduced accordingly to make a 5 gallon batch from a 6.5 gallon. My airlock gives off a bubble every 2.5 minutes now so did this jump start fermentation again?

 

[Tommyb52]

Measuring was simple with the 1 lb bags and a digital scale. I had the grains and brew pot in my oven steeping for 30 minutes at ~153 degrees.

 

[biochemedic]

Maltodextrin is an essentially flavorless addition, but it is unfermentable, as was mentioned before. How many pounds of grain did you actually use for your 5 gal modified recipe? How much liquid (ie; how many quarts per pound) did you mash with. Did you sparge your grain in some way?

If you want to add gravity without flavor, you need to add a fermentable simple sugar: dextrose, table sugar, candi sugar, etc. Be aware though, that these will thin out your body, and if you add too much can definitely affect the end product negatively. That being said, there are many styles that depend on simple sugars. Many Belgian styles are obvious examples, but also consider the really high gravity IIPA's where incremental dextrose additions are used to boost the effective OG.

 

[Tommyb52]

Mashed with 2.5 gallons and sparged with 1.5 gallons at 165 degrees and used about 11lbs of grain. The boil really evaporated the wort. I had to add about 3gallons to fill the fermentor to 5 gallons. Mash time was 30 minutes,maybe I need to mash longer(60 min.?)

 

[biochemedic]

I suspect your thick mash may have contributed to some of your poor inefficiency...0.9 qts/lb is pretty thick. Sometimes you can complete a mash in 30 min, but with the conditions at hand, a longer mash may be of benefit. You could consider doing a starch iodine test next time you brew to see when you are converting fully.

You had a total of 4 gal into the system, and probably lost about 1.6 gal to grain absorption, so boiling off another 0.4 gal isn't all that unreasonable. What sort of equipment are you using? How are you mashing/lautering/sparging (brew in a bag?)...are your volumes limited by the size of your kettle?

 

[Tommyb52]

I use a 5 gallon paint strainer bag to hold the grains in a big pot. When the pot reaches~155 deg. the grains go in and stirred till that temp is reached again. Then into my oven to steep @ a preset temp for 30 min. When thats done the bag goes into a colander over the pot to drip into the pot. Then I sparge over the bag @~165 deg. and let it drip again. I then cool the wort,aerate in the fermentor bucket,top off to 5 gallons and pitch yeast at 80 deg. Other than longer mash time, will pre soaking the grains help? If so how long and at what temp? Also since I was told that the malto dextrin I added wasn't fermentable(and a test gravity reading today of 1.012), I added 4 oz of table sugar diluted into 1 cup of boiled water to raise the alcohol because my ABV would only be 2.7 according to "daves dreaded calculator" http://dd26943.com/davesdreaded/tools/convert.htm All the info is greatly appreciated. The airlock is now bubbling once every 9 seconds.

 

[Tommyb52]

My air lock is now bubbling every 6 seconds.

 

[biochemedic]

I don't do BIAB technique, so perhaps some of the other BIAB brewers will be able to chime in more here...I'm wondering if perhaps you shouldn't actually be immersing the bag in your sparge water rather than pouring it over the grains in the collander. It seems to me as if that might allow a lot of the water to not really be passing through the grain bed but rather just around the bag.

Regardless, you will make beer... You just have a few adjustments to make for next time, and hopefully you can start to achieve some higher efficiency.