Missed OG Again!

[invmgmt]

Not sure what I am doing wrong but this is the third time and I am going nuts about it.

I am doing a batch sparge for the last two brews (Fly sparge on the first one).

My efficiency is great (80.7% according to Beer Smith) and I am hitting the pre-boil gravity each time. But my OG going into the fermenter was 1.044 instead of 1.046 per kit. Not much of a hit, but I added almost 2 lbs of honey (not in kit) at flame out which should have increased it to 1.052 per BeerSmith. I am using a converted keg as a kettle. after an hour of boil it only lost 1 gal to evaporation.

I don't think I am losing enough to evaporation but don't know how I can effect that.

Any thoughts out there from the group?

 

[jdauria]

Was going to say hitting 1.044 vs. 1.046 sounds like hitting your numbers to me...but then came the honey!

How are you determining your volume numbers? Are you estimating what you have after the boil? If you are suppose to have 6 gallons post-boil and only have 5.75 it can through readings off. Are you using a hydrometer to measure gravity? Are you cooling the sample before the reading? They are not very accurate at high temps. Are you taking your sample from the top of the kettle, or are you mixing it well after adding the honey and then taking a sample from deeper in the kettle?

 

[invmgmt]

I use BeerSmith for volume calculations. I also use BeerSmith to adjust hydro reading for temperature.

I use a wine thief to get the samples, so I guess it would be from mid-kettle.

 

[cjhammel]

To truly measure your efficiency you want to make sure you also measure your volumes both pre-boil and into the fermenter volumes. I created a dip stick for my kettle so I can watch my boil (I would like to get a sight glass that is in my wish list). The fermenting bucket has volume measurements so if you miss your volume this will effect the gravity readings as well. I find that when adding flame out sugars like honey or DME you really need to mix and incorporate them into the wort otherwise you can get some stratification of the sugars and have different hydro readings.

 

[invmgmt]

The volume going into the kettle from the MLT was spot on.

 

[Xpertskir]

So you hit your pre boil volume, pre boil gravity, and post boil volume...but not post boil gravity?

If that is the case then it has to be a measurement issue because if you hit any 3 of those 4, that's really the only thing it can be.

 

[mbach72]

I feel ya man. I just did my third all grain brew two days ago. I made a stout that is supposed to have a OG of 1.057. According to Brewers Friend, I hit the pre-boil gravity dead on. I'm certain the volume that went to the fermenter was spot too. However, I missed the OG by a pretty subsantial amount. My hydrometer sample showed 1.048 after temp correction. I'm keeping my fingers crossed hoping that my sample or reading was off somehow.

This is two in a row for me. I'm considering upping by grain bill slightly until I get things sorted out. I also wonder if my thermometer is off.

I'll be keeping my eye on this to see what kind of responses you get. Hopefully, I'll learn something too. The good news is, we both made beer and hopefully good beer, just a little lower abv than expected.

 

[shtoive87]

The amount of sugar in the kettle before the boil is exactly the same as the amount of sugar in the kettle after the boil (unless adding more sugar in the boil like the OP did). The only thing that changes is the volume due to boil-off. Seems like something screwy is going on with gravity readings or volume readings.