First PM - low OG

[bradneal]

Yesterday I did my first partial mash batch. It's a Norther Brewer Carmelite Triple-Grain Tripel, and as far as I could tell, all went according to plan. I sparged the grain through a mesh bag over a colander, and again, followed the instructions provided by NB pretty much to the letter. But when I did my OG reading, it came in at 1.066 instead of the targeted 1.081. A friend of mine had my refractometer, so I had to use my hdrometer, which I realize is not as accurate, but should be pretty close.

So anyway, other than lower alcohol, what affect will this lower OG have on the final product?

Thanks,
Brad

 

[Walker]

So anyway, other than lower alcohol, what affect will this lower OG have on the final product?

It could upset the desired balance of gravity and bitterness giving you a beer that is a lot more hoppy than you intended.

 

[bradneal]

Bummer! But for future reference, should I have backed off on the water and only brought it up until I reached the desired OG instead of filling it to the 5 gallon mark first?

Also, what is the most likely cause of the lower OG (assuming that I did everything right)?

Thanks for the reply.
Brad

 

[Walker]

Bummer! But for future reference, should I have backed off on the water and only brought it up until I reached the desired OG instead of filling it to the 5 gallon mark first?

Also, what is the most likely cause of the lower OG (assuming that I did everything right)?

Thanks for the reply.
Brad

There's several things you could have done after measuring that your mini-mash had low yield.

(1) bump the gravity back into alignment with more extract
(2) make a smaller batch than the planned 5 gallons (this would require your to reduce the hop additions)
(3) make 5 gallons of a lighter beer and adjust hops to bring gravity:bitterness ratio back into alignment.

What was your recipe, anyway?

 

[bradneal]

Here is a link to the ingredients. Also, I used a liquid yeast starter - Wyeast 3522 Belgian Ardennes.
http://www.northernbrewer.com/documentation/beerkits/PM-CarmeliteTripel.pdf

 

[Fletch78]

Was the wort temperature 138 degrees when you took the sample? That would throw off your hydrometer reading by the exact difference between 1.081 and 1.066

Conversion PDF: Bookmark or save it... you will use it often.

http://www.clanward.com/brewery_files/pdfs/HydrometerTemperatureConversionChart.pdf

 

[Walker]

Here is a link to the ingredients. Also, I used a liquid yeast starter - Wyeast 3522 Belgian Ardennes.
http://www.northernbrewer.com/documentation/beerkits/PM-CarmeliteTripel.pdf

This is really weird. If I leave out ALL of the grains listed for that kit and just plug the 6.3# of LME and 2# of corn sugar into ProMash, it yields 5 gallons of 1.063 wort.

That means that the 4.5 lbs of grain you used only added 0.003 gravity points. That's pretty much impossible.

I am suspect of your gravity reading now.

 

[bradneal]

...That means that the 4.5 lbs of grain you used only added 0.003 gravity points. That's pretty much impossible.

I am suspect of your gravity reading now.

Let's hope you're right!

 

[Walker]

Was the wort temperature 138 degrees when you took the sample? That would throw off your hydrometer reading by the exact difference between 1.081 and 1.066

Hmmm... leaving out the 2# of corn sugar comes pretty close to the missing 15 gravity points, too.

You didn't forget that part, did you?

 

[bradneal]

Was the wort temperature 138 degrees when you took the sample? That would throw off your hydrometer reading by the exact difference between 1.081 and 1.066

Conversion PDF: Bookmark or save it... you will use it often.

http://www.clanward.com/brewery_files/pdfs/HydrometerTemperatureConversionChart.pdf

No, the wort was cooled to about 68 degrees.

Thanks for the link. I book marked it.

 

[Bobby_M]

I don't understand why NB would suggest pouring sparge water over a strainer instead of just dunking the bag into the sparge water.

I'm also suspect of the thick mash. 5quarts for 4.5 pounds of grain is a bit thick. I would go with something like 2 gallons. Did you nail the mash temps at 152F for the hour?

 

[bradneal]

I don't understand why NB would suggest pouring sparge water over a strainer instead of just dunking the bag into the sparge water.

I'm also suspect of the thick mash. 5quarts for 4.5 pounds of grain is a bit thick. I would go with something like 2 gallons. Did you nail the mash temps at 152F for the hour?

I mashed for 1 hour at 152 +/- a couple degrees, brought it up to 170, and then pulled the bag from the water and poured the sparge water (also at 170f) over the bag about one quart at a time.