OG lower than expected

[Rixx]

Hi guys,

yesterday while brewing an American IPA I run into this problem:

- pre boil gravity 1.050 (39 liters)
- after boiling (OG) 1.054 (30 liters)

Actually my previsions were to have 1.065/66 at the end of the boiling.
Consider the fact that all my test were done at the right temperature (15°).
How can I explain this? I really would like to have a clue if you guys can help!!!

 

[BackAlley]

One of your measurements isn't right. 50x39/30=65 so if you really had 39l at 1.050 preboil and you really had 30l postboil your gravity should be 1.065

 

[Rixx]

I thought the same cause I did the same formula...the fact is i checked and repeated the test of gravity several times.

 

[kh54s10]

Were your test samples at the right temperature? That will skew the readings unless you calculate the conversion.

 

[Rixx]

I calculate the conversions with accurate data of reference. So I really can't explain how is it possible.

 

[BackAlley]

I thought the same cause I did the same formula...the fact is i checked and repeated the test of gravity several times.

Well something is wrong somewhere. Some possibilities are that you sampled a stratified wort, you used a temperature correction that's not accurate, your volumes were wrong, your original SG was wrong. You may not be able to figure out what your OG was without sending it to white labs for an ABV test at this point.


Sent from my iPhone using Home Brew

 

[Cajun_McChicken]

I've had something like this happen before (I thought I had achieved 115% mash efficiency... Lol). For me the problem was not stirring the wort before taking my pre-boil measurement and thus getting an artificially high reading from the sample I pulled (I had pulled only the first runnings through the port at the bottom of my kettle).

Did anything different happen with your mash that might lead to low efficiency?

 

[Rixx]

Cajun thanks for the advice...I guess this might be the problem as I didn't stir the wort maybe the result was distort by a stratified product