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Lower than expected OG

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150 degrees is a low mash temperature for saccharification efficiency. Which is why I would recommend anyone recreating this recipe to mash at 155 fahrenheit to get a better extraction rate, therefore a better gravity reading.

You should be able to get virtually 100% conversion efficiency, and whatever lauter efficiency is dictated by your equipment and process, at either temperature. IOW, mashing at 150F instead of 155F, won't, in and of itself, cause a hit to mash efficiency. But it will affect fermentability.
 
You should be able to get virtually 100% conversion efficiency, and whatever lauter efficiency is dictated by your equipment and process, at either temperature. IOW, mashing at 150F instead of 155F, won't, in and of itself, cause a hit to mash efficiency. But it will affect fermentability.

Explain IOW. I wonder why there was a documentation of a higher OG at 150F. Something was off from OP, right off the bat. The addition of tannins is all I can think of in terms of affecting fermentability. Steeping my grain for longer will be my next stab at this recipe; not that I care for higher alcohol (I do). Thermal equalibrium makes the temperature go towards ambient levels, which was 62F that day. Explain to me how it would affect fermentability.
 
Explain IOW. I wonder why there was a documentation of a higher OG at 150F. Something was off from OP, right off the bat. The addition of tannins is all I can think of in terms of affecting fermentability. Steeping my grain for longer will be my next stab at this recipe; not that I care for higher alcohol (I do). Thermal equalibrium makes the temperature go towards ambient levels, which was 62F that day. Explain to me how it would affect fermentability.
What's your question? I can't figure it out from the word salad you wrote.

If you want to know how to diagnose mash efficiency issues (typically lower than expected OG) I suggest you read the following post. If there is something in there you don't understand then ask detailed questions ("I don't understand, please explain" is not a useful request for help.)

OP's issue was an OG measurement that was lower than their pre-boil SG measurement. This is physically impossible. If you have measurements like this, your measurements are in error. It's that simple. Before you can diagnose efficiency problems, you have to fix your measurement problems. If the data is bad, you can't use it for problem solving.

Brew on :mug:
 
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I don't know what IOW means. He's not making it clear Doug293cz. I have 12# grain to 4 gallons strike water, with 1 sparge water additions.

After overlooking your post Doug293cz, it says that my lauter efficiency is lower overall.

If you are suggesting that I made an error, I would say that I was precise and accurate to the best of my abilities brewing a batch of beer.

Thanks for the input.
 
"IOW" = In Other Words

As @VikeMan implied "conversion" does not necessarily imply a degree of fermentable wort. In theory one could have the same recipe result in a highly fermentable wort or a dreadfully poorly fermentable wort, both with the same degree of "conversion", but with the percentage of dextrins resulting from radically divergent mash temperature profiles making the difference...

Cheers!
 
Explain to me how it would affect fermentability.

Each of the enzymes involved in breaking down starches has a characteristic temperature at which it's most efficient, i.e. where it's able to work fast in comparison to the rate at which it denatures. And, each enzyme works (cuts) at different parts of carbohydrate structures. The result is that the mix of various fully fermentable sugars, partially fermentable sugars, and unfermentable dextrins in the wort depends on the mash temperature (among other things).

For the two temperatures in your example, 150F will, all else being equal, produce a wort that is more fermentable than 155F.

That said, both mashes, if properly executed, will result in the same mash efficiency, i.e. with virtually all of the starches converted to sugars and dextrins, and with the same amount of total carbs (sugars+dextrins) making it into the boil kettle.
 
"IOW" = In Other Words

As @VikeMan implied "conversion" does not necessarily imply a degree of fermentable wort. In theory one could have the same recipe result in a highly fermentable wort or a dreadfully poorly fermentable wort, both with the same degree of "conversion", but with the percentage of dextrins resulting from radically divergent mash temperature profiles making the difference...

Cheers!
That's what it means, thanks a lot!

I did not know that about fermentable wort, thanks for bringing that to my attention.

So its not the temperature of the wort, but the quality of the grain basically. The consistency, or quality of carbohydrates matters for the saccarification to be matched.
 
I have found this thread confusing in the extreme! o_O 🤣
It seems simple enough pre boil and post boil SG x volume did not match two possibilities errors were made in estimating wort volumes or gravities or some wort was lost somewhere ... there are no other ways of explaining this ... what has the mashing got to do with anything ??? That happened before the vols and gravities were estimated o_O
 
So its not the temperature of the wort, but the quality of the grain basically.

In regard to the total amount of sugars and dextrins that can be produced, yes, it's the types and quantities of grains that matter, because they determine the amount of starches available to convert.
 
Using a refractometer to keep track of gravity readings throughout brew day is fast and efficient. But you can't simply take a hot drop of wort out of the kettle and place it on the prism. The reading will be badly skewed due to evaporation of the hot wort.
This is an excellent point. That might explain why my hot samples always have a higher gravity than expected. Thanks, I've never realized that
 
This is an excellent point. That might explain why my hot samples always have a higher gravity than expected. Thanks, I've never realized that
At the beginning of the boil I would just give the wort a stir and let the spoon drip onto the prism and every time it would read exactly what the FG ended up being.
 
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