Low OG

[jmcooley1991]

Just looking for some guidance on what may have happened to my Original Gravity. We took a pre-boil sample that was right on track. But, after being crash cool before pitching yeast are sample was really low. Does anybody have any ideas about what could cause it to change so much during our boil?

 

[VikeMan]

If your pre-boil OG was right on, and your post-boil OG was lower than expected, you must not have boiled off as much water as expected.

 

[myndflyte]

We need some more information to help. What was the recipe, what were the OG numbers, what were your volumes, ect.

 

[day_trippr]

I bet the "crash cooling" caused stratification, and if the sample was drawn near the top may well be thinner...

Cheers!

 

[MikeCo]

Are you using a hydrometer or a refractometer? If using a hydrometer, did you cool the pre-boil sample to the calibration temperature? If not, it would read low, which I guess is not the problem. If using a refractometer, if it's a low cost type like I have, I always take several samples because they vary a lot and the small sample size is a source of error if the wort is not mixed well.

As VikeMan said, if boil-off rate is lower than assumed, it will result in lower OG than planned. Was the post boil volume more than targeted?