Another odd thing happed on brew day

[hilljack13]

I brewed the Pizza Ports Red Ale kit last week. Once the mash and sparge was complete, I drew a sample and cooled it to 20C. My SG at that time after three refractometer readings was only 1.023. I almost sh*t myself. I use a Grainfather G40 and this time I didn't "squeeze" the grains. However, after the reading I went back to do this. Now, the basket had already been removed from the unit and was no longer dripping so I was only able to squeeze a few cups of wort, but not as much as I have before (~half gallon).

Time for a second reading. Same as previous, but now I am getting 1.070 SG!!! WTF? I have been able to get 3-4 times more wort out of squeezing the grains and only get at most 5-8 points. I even rechecked the refractometer with water and it was spot on 0.00. No clue what I did, but I know the added wort did not get the SG that high.

Has this happened to anyone? I must be overlooking something as to why I got the readings.

 

[hotbeer]

It'd be nice if you also checked with a hydrometer just to make sure there isn't something going awry with your use of the refractometer.

I have trouble believing that squeezing the bag gets materially more sugar laden wort.

I understand that refractometers are convienient for making quick checks. But for OG and the actual FG just before bottling or kegging, I'd want the reading from the tool that can actually measure specific gravity instead of the refraction of light.

So yes, my thoughts are that you didn't do something correctly. Hope that doesn't hurt. Let's have a beer!

 

[Drinking Sensibly]

Very much guessing because I don't know how a Grainfather works but is it possible the wort wasn't mixed so you had layers of more concentrated wort from first run off with diluted wort after sparging on top?

 

[mac_1103]

I would go way out on a limb and guess that both readings are wrong and the most likely reason is that the wort wasn't mixed well enough. You say you brewed this last week, so what was your (post-boil) OG?

 

[hilljack13]

I just realized I posted the OG (post boil cooled), which was 1.070, the pre-boil after the squeeze was 1.048. Still a lot higher than 1.023 and only .002 higher than expected.

I do have a hydrometer but got out of using it except to check FG. Guess I need to start double checking.

As for the wort mixing, the Grainfather has a continuous recirculation and I keep that going because I do filter out what grain escapes the basket. Separate issue there.

 

[mac_1103]

So just playing around with Brewer's Friend, 1.048 and 1.070 would be expected from that grain bill if efficiency is 84%, pre-boil volume is 8 gallons and post boil volume is 5.5 gallons. The 1.023 has to be an error of some kind.

I do have a hydrometer but got out of using it except to check FG.

I would use it for OG too. That way you're comparing apples to apples when you try to figure out attenuation and ABV.

 

[hilljack13]

Not sure if this helps, but this is the BrewFather app stats. I highlighted the problem area. I always seem to be within a few points of pre-boil SG and way above what OG should be.

 

[Drinking Sensibly]

If you're consistently achieving higher brewhouse efficiency than your recipe predicted, surely you should change the recipe efficiency figure so it's predicting more accurately in the future?
I work on 80%. 69% seems like a low figure for a recirculating/fly sparge system, which I assume the Grainfather is.

 

[mac_1103]

If you're consistently achieving higher brewhouse efficiency than your recipe predicted, surely you should change the recipe efficiency figure so it's predicting more accurately in the future?

Yeah, but there's still something squirrely going on. You can't create gravity points during the boil. (48*7.75)/6.25=59.5; so how is he getting to 1.070? There has to be an error in either a gravity or a volume measurement. Maybe both.

 

[hilljack13]

I started doing a 75 min mash. For whatever reason, when I stay at 60 I never hit my numbers. Like 6-8 points low pre/post boil. I also started using the Spike mill a few months ago.

Is the 59.5 the an efficiency number? I haven't tried to do this manually. I use mash efficiency when putting recipe's together, but I try to say ~75%. The one time I went 80% everything was thrown off and I had low numbers.

Would the post boil volume being a .25 gal low push the gravity that high? I guess I should have topped off the FV to my usual 5.5 gal and took another reading.

 

[Skeeter686]

I do have a hydrometer but got out of using it except to check FG. Guess I need to start double checking.

I've checked my refractometer against my hydrometer a number of times, and the readings are within about 0.002 of each other. It wouldn't hurt for you to do similar evaluations, but I've got enough confidence that my refractometer readings are "close enough" that I no longer check with the hydro. Unless something really seems off... and in those cases, I find that I'm still within about 0.002 and that I've obviously screwed something up (i.e., it's not a bad reading).

 

[mac_1103]

Is the 59.5 the an efficiency number?

Sorry that wasn't clear. 1.0595 is what your post-boil gravity should be if your pre-boil gravity is 1.048 and your pre- and post-boil volumes are 7.75 gallons and 6.25 gallons respectively.

 

[BrewZer]

I have trouble believing that squeezing the bag gets materially more sugar laden wort.

Spoken like one who has never squeezed the bag. You'd be surprised how much wort gets held in the biomass, and how sweet it is (not a reference to Jackie Gleason).

 

[hotbeer]

Spoken like one who has never squeezed the bag. You'd be surprised how much wort gets held in the biomass, and how sweet it is (not a reference to Jackie Gleason).

I squeeze the bag often enough if I don't get the volume I expected to put in the FV and the SG is my predicted OG. Which makes adding water to the wort undesirable if I want to have the expected amount in the FV.

What I doubt is that the stuff coming from the bag has much is any increased amount of sugars in it than what has already drained from the bag. I'd expect both to be close enough to the same SG and even if it was quite a few points higher, not enough to make a significant difference in the SG of the wort already drained from the bag.

The OP even said that squeezing didn't give them much additional wort this time compared to other times.

 

[hilljack13]

I did it again...
Today I brewed the A Christmas Ale from NB. Pre boil SG was 1.051 and post boil was 1.079. Readings took at 20C. Expected 1.057 and 1.073 respectively. My FV ended up a tad higher. I was going for 5.25 gal and ended ~5.40 gal. It was just a bit under the half gallon mark. If anybody likes strong beers without adding sugar I'm your guy.

 

[mashdar]

How are you pulling samples, and when? E.g. immediately after sparging? The little pump in the grainfather would take a while to mix thoroughly. Does it run during sparge?

(edit: easy solution is to stir if you want a pre-boil sample)

 

[hilljack13]

How are you pulling samples, and when? E.g. immediately after sparging? The little pump in the grainfather would take a while to mix thoroughly. Does it run during sparge?

(edit: easy solution is to stir if you want a pre-boil sample)

I take the first after sparging and the pump isn't running since the basket covers the outlet. Use a pipette to put in a SS shot and cool to 20C. Last is done after boil, same process.

Side note, sometimes I take a reading just before the mash ends. Why? just to do it. Today I did and presparge was 1.060. I added 1.5 gal of sparge water.

 

[mashdar]

That's the issue - your wort is first runnings on the bottom and sparge runnings on top with potentially "bubbles" of first runnings floating up (particularly if heat is on).

Post-boil will be much more uniform.

 

[hotbeer]

I did it again...

What is it?

And what troubles you about this?

Today I brewed the A Christmas Ale from NB. Pre boil SG was 1.051 and post boil was 1.079. Readings took at 20C. Expected 1.057 and 1.073 respectively. My FV ended up a tad higher. I was going for 5.25 gal and ended ~5.40 gal. It was just a bit under the half gallon mark. If anybody likes strong beers without adding sugar I'm your guy.

The disparity between predicted and actual are just showing that you still have some work to figure out and adjust for mash efficiency and boil off correctly in your beer software's settings for equipment and such.

But still it'll be beer!

As well, more info about wort volume at the time of each of those readings can help us figure out better if you are amiss with something. And knowing water used to mash wort volume made too. Along with the fermentable ingredients.

 

[hilljack13]

What is it?

That I seem to be right on my pre boil gravity but way over the OG. Was 7 points over. One of my concerns is when I attempt to do a german lager/pils that the ABV is going to be too high and the profile won't be there. I'm still working on my 1 gal batches to find a recipe I like.

Would it help if I posted the equipment profile? The only thing I changed this go around was the FV volume from 5.5 to 5.25. Only because I always have some left in the kettle. This time all the kettle was emptied, and I was just under 5.5....Got to figure that one out.