What’s the impact to my OG ?

[Keruso]

Did a brew today using WLP570 Belgian golden ale. Made a 3 litre starter 48 hours before brew day. Yeast is known for its low flocculation, I didn’t get a chance to cold crash the starter, so most of the yeast was still in suspension. I had no choice but to chuck all 3 litres into the fermenter with the wort. To compensate for the starter volume I added 200g of dextrose to the boil, bit of guess on how much, the SG of the wort before adding the 3 litre starter was 1.076. I estimate the starter was around 4.2% ABV. Is there an easy way to work out what the likely OG was after adding a 3 litre starter to approx 20 litres of wort at 1.076. I could of given a it a stir and taken another reading but couldn’t be bothered at the time. Brewers friend has a dilution and boil off calculator but of course it’s for water and not a starter. Thanks

 

[The Baron]

think you could up the volume in Brewers friend to the full volume inc the 3 litres starter this will bring your OG down now add 200g of sugar to the ingredients and it should work out your new OG

 

[strange-steve]

Assuming your starter began at about 1.040 then your effective OG can be worked out like so:

(40 * 3) + (76 * 20) / 23
= 71

So an effective OG of 1.071.

 

[Keruso]

Assuming your starter began at about 1.040 then your effective OG can be worked out like so:

(40 * 3) + (76 * 20) / 23
= 71

So an effective OG of 1.071.

Thanks Steve, so not too far off thankfully

 

[Keruso]

think you could up the volume in Brewers friend to the full volume inc the 3 litres starter this will bring your OG down now add 200g of sugar to the ingredients and it should work out your new OG

I see what you mean, fiddle with the recipe to predict the likely OG, good idea cheers