Why is my wheat beer sour?

This wheat has been in the keg for a few weeks and has a very obvious sour/tart flavor to it. It was fermented around 64F.

Any ideas on where the flavor is from? I was going for more banana flavor and this was definetly a swing and a miss...

Size: 5.5 gal
Efficiency: 75.0%
Attenuation: 75.0%
Calories: 152.78 kcal per 12.0 fl oz

Original Gravity: 1.046 (1.044 - 1.052)
Terminal Gravity: 1.012 (1.010 - 1.014)
Color: 2.99 (2.0 - 8.0)
Alcohol: 4.52% (4.3% - 5.6%)
Bitterness: 11.0 (8.0 - 15.0)

Ingredients:
4.0 lb 2-Row Brewers Malt
5.0 lb Wheat Malt
.5 lb Wheat Flakes
.75 oz Hallertau (3.8%) - added during boil, boiled 60.0 min
.25 oz Hallertau (3.8%) - added during boil, boiled 10.0 min
0.0 ea WYeast 3068 Weihenstephan Weizen



Notes
Wyeast 3068 used.


Used 1.33 quart per pound of mash water at 165f.....3.15 gallons mash water
Used 1/2 gallon per pound of sparge water for 20 min. at 170f...........4.75 gallon sparge water

You fermented a little too low to really get a banana character out of the yeast you used. A sour/tart flavor could be from an infection, but it might just be young. A few weeks should be enough in a keg, but you never know. It could tuen a corner and taste fine soon.

The only thing I see out of the ordinary in your recipe is your mash temp.

Most mashes are at 155F. Based upon that it could be tannins from the hulls adding the sour flavor. I've never experienced it, but that's just my guess.

Germans also ferment in the low 60's so I don't think that is the problem, but if you're looking for a more pronounced banana flavor it should ferment in the 70s. Others may argue the point, so there's no use getting bent out of shape with an alternate opinion.

Should anyone else see something I don't, please, chime in...

I wonder how your beer compares to commercial examples.

I am drinking a hefe that has a decided citrus-y finish to it. But I love it. And it is something that I can pick out in a lot of hefes. Mine has been in keg about six weeks now but it has been delicious since about three weeks in keg.

(I am assuming the mash water temp you quote is actually the strike water temp and that you mashed at a considerably lower temp.)

dontman said:

(I am assuming the mash water temp you quote is actually the strike water temp and that you mashed at a considerably lower temp.)

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I don't think so. He stated:

Used 1/2 gallon per pound of sparge water for 20 min. at 170f...4.75 gallon sparge water.

Which sounds OK to me.

Should have clarified the mash temp. I heat the water to 165f and dump into the MLT/cooler to heat it up. It takes a few min to drop to 155f and then the grains go in (dough in??) and that seems to prevent too much heat loss while mashing due to the cooler already being warmed.

Check your water/mash ph - could be too acidic.

usurpers26 said:

Check your water/mash ph - could be too acidic.

Click to expand...

+1. My understanding is that the sour nature of wheat beers can be due to lower pH. Did you use all bottled or spring water or straight from the tap? There's a huge difference in my tap water pH and spring water bought from the store. My tap water is close to pH 8 and the stuff from the store is just below 7.

I also think that the wheat itself causes a more sour taste. But I dont have any facts to back that up, I recall reading that somewhere.

One point of reference is that every time I make wheat beers I also get sour notes (which I like in wheat beers). I use 100% bottled water from the store with these beers, so I know the pH is on the lower side.

Was 64 the temp the air was or the temp in the beer itself, I have a temp probe in the center of my fermenter that gives me the real temp. If you talking ambient temp the beer was most likley 10 degrees higher and that would give it some twang.

Pat

I think the Jamil Show episode on Weizen beer brewing mentioned that wheat itself doesn't make a sour taste, it's either the yeast or something in the process.

I brewed the NB extract honey weizen kit for a BBQ in July and got a sour flavor from it, but it seemed to be at a normal, tolerable level. In fact, when I was at the Rathaus brewpub in Luzern, Switzerland last month, their weizen tasted exactly the same as my extract brew.

The fermenter "chamber", a cooler full of water with my primary bucket in it, was at 64f. I used a scoop of 5.1 to help stabilize the PH which has seemed to work fine in the past.
It is tolerable, but not what I what I was shooting for.

Your recipe looks very similiar to EdWorts Bavarian Hefeweizen.

https://www.homebrewtalk.com/f70/bee-cave-brewery-bavarian-hefeweizen-35679/

Shoot EdWort an email and see what he says. My guess is that it's the Weihenstephan 3068 yeast that's giving it that soured taste.

A lot of wheat beer yeasts are sour, that's why I hate wheat beers, but I love wheat. I also have no use for banana/clove, etc, esters in my beers...

I want to do a wheat with a neutral yeast just to see what it's like.

I don't see why others haven't been doing them already; at least I don't see those recipes.