Stuck at 1.040 - Trying to find cause and possible fix?

[cercueil]

Cause of low ending gravity

Reason 1 - Not enought oxygen in the wort. I don't have an o2 setup yet and simply mixed the wort for about 10 minutes with my mash paddle

Reason 2 - Mash temperature was too high? I mashed at about 155 but maybe my thermometer was way off? Would a mash at lets say 160 cause all those unfermentables?

Possible Resolutions

1. I tried another packet of hydrated dry yeast (windsor)
2. Removed about 32 ounce of beer into growler. Shook it up and re-pitched different yeast (muntons)

Not a single move in hydro. I read somewhere that someone tried pure 02 and got theirs to restart. At this point I dont think I can do anything about it but I'm trying to learn from this one. Here is the recipe below:



Type: All Grain
Batch Size: 5.50 gal
Boil Size: 6.30 gal
Boil Time: 60 min
Brewhouse Efficiency: 65.00%

Grain

15.00 lb Maris Otter
1.50 lb Oats, Flaked
1.00 lb Chocolate Malt
0.75 lb Roasted Barley
0.50 lb Caramel/Crystal Malt -120L

Hops
1 oz Nugget [13.00 %] (60 min) Hops 34.5 IBU
1 oz Centennial [10.00 %] (45 min) Hops 24.3 IBU
.5 oz Williamette [5.50 %] (30 min) Hops 11.2 IBU
.5 oz Williamette [5.50 %] (0 min) Hops -

Adjuncts
8 oz Unsweetened Chocolate (Boil 0.0 min)
1.00 oz Coconut Extract (Boil 5.0 min)
1.00 oz Almond Extract(Boil 5.0 min)
1.00 oz Vanilla Extract(Boil 5.0 min)


Est Original Gravity: 1.078 SG
Est Final Gravity: 1.020
Estimated Alcohol by Vol: 7.64 %
Bitterness: 70.0 IBU

Total Grain Weight: 18.75 lb

60 min Mash - Add 23.44 qt of water at 167.1 F for 155.0 F Mash Temp

2 Packets - Safale US-05

 

[broadbill]

Did any of your adjuncts have preservatives in them?

 

[yeqmaster]

How did you sparge? Did you calc ur efficiency based off your low OG?

 

[JesseRC]

Did any of your adjuncts have preservatives in them?

+1 I would check for preservatives. I would have adding these at kegging time or secondary.

 

[yeqmaster]

65% got it... thats not too bad... I would guess that it is an issue with aeration... Maybe try investing in a simple fish tank pump setup..

 

[cercueil]

Wow..Thanks for pointing this out about the preservatives..I never really thought about this. I saw recipes with flavor extracts in them and apparantly I must have thought they went in at the end of the boil. So I guess the preservatives have some effect on how yeast convert sugar? I guess they interfere in some way.

 

[broadbill]

Wow..Thanks for pointing this out about the preservatives..I never really thought about this. I saw recipes with flavor extracts in them and apparantly I must have thought they went in at the end of the boil. So I guess the preservatives have some effect on how yeast convert sugar? I guess they interfere in some way.

By definition, perservatives are added to prevent growth of microbial growth, say yeast as an example! So yes, preservatives will directly interfere with yeast growth.

That being said, many extracts are made with alcohol....alcohol acts as a solvent to extract whatever flavor componets you put in it. Because of this, many extracts really don't need additional perservatives, but that doesn't stop manufacturers for putting them in.

 

[samc]

I can tell you that

Reason 1 - Not enought oxygen in the wort. I don't have an o2 setup yet and simply mixed the wort for about 10 minutes with my mash paddle

is not an issue - you don't need to aerate the wort if using S-05 or any quality dry yeast. They are prepared in such a way to provide the necessary components that the yeast need to grow properly. Liquid yeast needs the proper aeration. Check Fermentis or Danstar websites for further info if you are in need of the facts on this.

I see no mention of fermentation temperatures - what are they?

 

[broadbill]

I can tell you that

Reason 1 - Not enought oxygen in the wort. I don't have an o2 setup yet and simply mixed the wort for about 10 minutes with my mash paddle

is not an issue - you don't need to aerate the wort if using S-05 or any quality dry yeast. They are prepared in such a way to provide the necessary components that the yeast need to grow properly. Liquid yeast needs the proper aeration. Check Fermentis or Danstar websites for further info if you are in need of the facts on this.

I see no mention of fermentation temperatures - what are they?

+1 to this. Furthermore, if it was an oxygenation issue in your first pitch, then you would have had fermentation and a gravity drop with the second pitch of windsor yeast.

Lack of oxygen hinders the yeast reproductive phase and causes yeast stress, resulting in a stuck gravity because the yeast go dormant and flocculate before finishing the job. A fresh pitch of healthy yeast would then finish the job. Since this did not happen, there is something else going on.

 

[gturner6ppc]

Let's see. Going from this - http://www.mccormickgourmet.com/content.cfm?id=7030

McCormick Pure Vanilla Extract:
Ingredients
VANILLA BEAN EXTRACTIVES IN WATER, ALCOHOL (35%), AND CORN SYRUP.

McCormick Pure Almond Extract:
Ingredients
WATER, ALCOHOL (32%), AND OIL OF BITTER ALMOND.

So far, so good, but perhaps you used something like McCormick's Bakers Imitation Vanilla Extract.

Ingredients
WATER , PROPYLENE GLYCOL, VANILLIN, CARAMEL COLOR, 0.1% SODIUM BENZOATE (ADDED AS A PRESERVATIVE), PHOSPHORIC ACID, AND ETHYL VANILLIN .

And then there is this:

McCormick Imitation Coconut Extract:
Ingredients
WATER, ALCOHOL (21%), PROPYLENE GLYCOL, AND ARTIFICIAL FLAVORS.

and

McCormick Imitation Almond Extract
Ingredients
WATER, ALCOHOL (32%), AND BENZALDEHYDE.

I'd check the labels on what you actually used.

ETA: Benzaldehyde is okay. It's the natural flavor in almonds and occurs in apples and apricots.

ETA 2: See if your extracts had sodium benzoate as a preservative. From the Wiki:

Sodium benzoate is a preservative. It is bacteriostatic and fungistatic under acidic conditions.

The mechanism starts with the absorption of benzoic acid into the cell. If the intracellular pH changes to 5 or lower, the anaerobic fermentation of glucose through phosphofructokinase is decreased by 95%.

Ouch. Stops the fermentation of glucose!

 

[cercueil]

I actually used these extracts which is exactly what gturner6ppc said:

McCormick Pure Vanilla Extract
McCormick Pure Almond Extract
McCormick Imitation Coconut Extract

I specifically tried to use pure extracts but I wanted to use them for taste reasons and not specifically that they didn't have preservatives. There was no pure coconut so I went with the imitation one. The fermentation temps were room temp which was about 70. Maybe it was the coconut one that messed it up.

 

[gturner6ppc]

The imitation coconut has propylene glycol, but I think that's pretty benign.

*goes and looks*

It does have anti-fungal properties (and is used in some skin ointments to fight yeast infections) but to be effective in a solution takes a concentration of around 30 grams per liter. That would be about a pound of propylene glycol in a 5 gallon batch.

 

[cercueil]

I took out about 32 ounces from the carboy and put it in a growler with an airlock. I shook it up and pitched some rehydrated muntons yeast in there. I checked it about a week later and it did go down a little bit to 1.030. The weird thing is I didn't see any bubbles at all in the beer while it was fermenting. I tasted the beer and it wasn't that bad. So I rehydrated the rest of the Muntons and shook the carboy (taking a chance here) and pitched the yeast. I figure I will give it a couple weeks to see if it moves at all. Hopefully if it goes down a little I'll throw it on tap and see how it goes.