OG on partial boil ?

[TheArmada]

I'm a fairly small-time brewer and I was wondering how one would go about the following situation:

I'm boiling 5 liters of water (wort) and adding 5 liters of water as a base to my carboy. Of course I am doing everything as if my wort was 10 liters.

My question is what would be the best way to register Original Gravity in this situation ? Will taking OG on the 5 liters wort be accurate enough even if I am pouring it into 5 additional liters afterwards ?

I ask because I don't wish to take a sample out of my carboy once all 10 liters are in for risk of contamination.

Thank you in advance.

 

[chickypad]

Yes if you're volumes are accurate you can take the OG of your 5 liters and divide the gravity points by 2. But if it's an extract batch you can pretty much just go with the calculated OG, again if your volumes are on.

 

[woozy]

I'm confused. Are you doing 2 batches of 5 litre wort or 5 liters of concentrated wort and will top off with water?

Either ways the answer is the same. Take a reading of each and average the result.

If you are topping off with then assume the water is 1.000.

 

[Yooper]

I'm a fairly small-time brewer and I was wondering how one would go about the following situation:

I'm boiling 5 liters of water (wort) and adding 5 liters of water as a base to my carboy. Of course I am doing everything as if my wort was 10 liters.

My question is what would be the best way to register Original Gravity in this situation ? Will taking OG on the 5 liters wort be accurate enough even if I am pouring it into 5 additional liters afterwards ?

I ask because I don't wish to take a sample out of my carboy once all 10 liters are in for risk of contamination.

Thank you in advance.

How would talking a sample of wort out of the carboy risk contamination? I'm not sure how that would happen, and I'd venture a guess to say that the vast majority of brewers and winemakers DO take samples of their completed wort.