Does Straining Wort Affect OG?

[GHBWNY]

I just did a batch of Cal. Common. Rec'd OG is 1.048-1.053. Mine came in at 1.045. Not sure why, as I followed the instructions to a tee. This was the first time I strained wort into the ferm bucket and wondered if straining out potential fermentables resulted in the lower OG?

 

[smalltownbrewer]

Its possible that you thinned your wort out slightly. Were the temps the same both times? temp will also have an impact on OG, also had it settled before testing your gravity. There are numerous reasons why you did not reach the target OG. but 1.045 is still pretty decent.

 

[m1batt1]

Or were you a little high on volume post boil?

 

[kh54s10]

Assuming an extract kit with top up water. If so, you used all the ingredients and ended up with the proper volume. It is likely the wort and top up water was not fully mixed. This is a fairly common thing. If your fermentation has not started you could take another reading. If it has or you don't want to take another reading (and it is an extract kit) you can use the predicted OG. It would be within a point or two.

 

[GHBWNY]

Assuming an extract kit with top up water. If so, you used all the ingredients and ended up with the proper volume. It is likely the wort and top up water was not fully mixed. This is a fairly common thing. If your fermentation has not started you could take another reading. If it has or you don't want to take another reading (and it is an extract kit) you can use the predicted OG. It would be within a point or two.

Yes to above. However, I had stirred it several times during cool down to de-stratify temp, so I don't think top-off water was an issue.

5 hours after pitching, I re-agitated the wort and took another reading --- still 1.045. If I make an adjustment for temp at OG, it might be closer to 1.046. So, from what I've read here, it sounds as if straining off the hop/grain slurry from brew kettle to ferm bucket might have an effect on OG reading...?

 

[duboman]

Straining the wort should have no effect on the OG reading because you are not straining out the sugars, only the trub.

Most likely the top off water was in fact your issue. It is very difficult to get the more dense wort to completely mix uniformly with the water even with two separate readings after mixing. This is a very common issue.

The fact is that when brewing extract, as long as you hit your volumes correctly the OG is what the recipe states because the extract has a fixed potential gravity.

 

[Trox]

The only way straining is going to affect your OG is if you have a strainer able to strain the sugar particles out of the water; which at the homebrew level is probably next to impossible. Since it is an extract kit it is probably one 2 things; your volumes is greater than what is called for in the kit, or your wort and top off water isn't fully mixed.