Beginer all grain question

What went wrong? Was this supposed to happen? Should I throw it out? What do I do now?

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Beginer all grain question

Postby river water brewing » Wed Nov 04, 2009 12:13 pm

Hello, so i did my first all grain about 2 weeks ago and i have a question about the results

first of all i had low efficiency (65%), but i think i need to mill my grains finer (but to be cautious of not getting them too fine) another patron of my HBS said that he has them mill it twice to get the proper mill. I also had a little trouble hitting my mash temp (even using beer tools) so i have added a recirculation system so i can circulate my mash water through a heat exchange and back into the mash tun, i use a 10gal cooler system so i cant add heat to my mash tun and want to keep to a specific grist to water ratio. Does a thinner mash help get a better efficiency?

second of all i had attenuation problems, i only got to 65%, i am used to getting to 80% when i was doing extract / specialty grains recipes so i know my methods are good and clean. i have been doing some reading, so tell me if my theory is correct. can i convert enough sugars to hit my target (or close to) OG but yet not convert the sugars into ferment-able sugars? could it also have been my ratio of specialty grains to base gran? i had 12lbs of base malt and 3lbs of specialty grains. according to beer tools (DBFG/DBCG) most of my specialty grains were between 64% and 75% ferment-able, or is this how much can be extracted and would not have an effect on the ferment-ability of the wort produced??

any thoughts on my situation would be greatly appreciated!!!
JG
Just trying to find the perfect batch!!!
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meant to mention

Postby river water brewing » Wed Nov 04, 2009 12:55 pm

sorry meant to mention here is my mash schedule:

dough in for 20 min wanted to hit 104 but temp hit 110
sac rest for 60 min, wanted to hit 152 but temp only got to 149
grist to water ratio was 1.2qts to each lb of grain
i used 1 tablespoon of ph stabilizer during the mash
then i did a mash out to get the temp up to 170 but only got it to 155

could any of this contributed to my efficiency or attenuation problems?
JG
Just trying to find the perfect batch!!!
river water brewing
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mash efficiency

Postby slothrob » Wed Nov 04, 2009 7:51 pm

I've seen good data from Kai Troester that suggests that a 1.5-2.0 qt/# thickness (or even a little higher) can improve efficiency over thicker mashes.

Your mash temperatures are in the range to promote fermentability, i.e, below 150°F, but these low temperatures can also sloe conversion. Some brewers will mash for upwards of 90 minutes if they are mashing at lower temperatures, to insure complete conversion and to give the converted starch time to set fermentability. I usually do a step mash when mashing below 150°F. For example, for an Alt that I want to finish dry, I mash at 148°F, but then bump up to 155-162°F for around 20' to ensure that conversion has completed.

If conversion doesn't complete, you'll take a hit in efficiency. It takes some time to set the fermentability of the extract evan after conversion, so slow conversion could lead to lower fermentability.

You should also check your thermometer calibration to make sure you are mashing at the temperature you think you are. A few degrees lower or higher can make a difference, and some people find their thermometers are off by as much as 10°F.

Specialty grains can make a dramatic difference in fermentability. Each pound of Crystal Malt can add 2-3 points to your finishing gravity, as it is only about 50% fermentable. Toasted malts, like Munich and Vienna, are about 85% fermentable, so they can add another point per pound to the FG.

Of course, yeast choice is one of the greatest influence on attenuation, making it difficult to compare one batch to another unless they both were made with the same yeast.

By the way, I think you misunderstand the meaning of DBFG and DBCG. These are measures of the percentage of starch available for conversion. They represent a reference to be used to calculate efficiency, not fermentability.
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Thanks so much!!!

Postby river water brewing » Mon Nov 09, 2009 3:03 pm

As always slothrob you are awesome!!!

I did another batch this weekend, i got to 76% efficiency. I did a very similar multi step mash as you described so i am anxious to see what kind of attenuation i get. i have bubbles coming from my blow off within an hour and overflowing out the blow off within 12, looks promissing.

Thanks again so much!!! Your support is greatly appreciated!! :D
JG
Just trying to find the perfect batch!!!
river water brewing
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Location: Sacramento CA

efficiency

Postby slothrob » Tue Nov 10, 2009 7:42 am

It sounds like you might have been have low conversion efficiency, then.

Glad it helped, and good luck with the beer!
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