Efficiency

[hhouken]

When I take a gravity reading at the end of the mash do I need to correct for temperature in order to calculate the extraction efficiency? I am using the example in John Palmer's book page 192, 3rd edition if that helps.

 

[raven19]

If you are using a hydrometer, then yes correction is required (or chill it in an ice bath) down to 20 deg.

Using a refractometer you don't need to correct for temperature (the small sample volume cools quickly when applied to the viewing glass).

 

[peaky]

When I take a gravity reading at the end of the mash do I need to correct for temperature in order to calculate the extraction efficiency? I am using the example in John Palmer's book page 192, 3rd edition if that helps.

Do you mean lower the temp to get an accurate reading?

If you're using a hydrometer, yes. If you're using a refractometer, no. If using a hydrometer, cool the wort to the temp your hydrometer is calibrated at. Most are 20 degrees, some are 18 degrees.


Disclaimer: I've never read John Palmer's book so I'm not sure what page 192 says..... :icon_cheers:


EDIT: I type too slow.....

 

[stux]

I think you need to correct the volume of wort for temperature too in order to get an accurate efficiency

 

[seemax]

Beersmith (& others) have a hydrometer correction tool , just enter the SG and temp ... or cool it down.

 

[warra48]

I think you need to correct the volume of wort for temperature too in order to get an accurate efficiency

I asked a question about this some time ago on the BeerSmith Forum.
The answer was that BeerSmith does not take this into account in its calculations in the Hydrometer Tool.
I don't know whether BeerSmith 2 now does or not.

Does anyone have a table as to the % shrinkage of wort at various temperatures between say 20C and 100C ?

 

[wessmith]

I asked a question about this some time ago on the BeerSmith Forum.
The answer was that BeerSmith does not take this into account in its calculations in the Hydrometer Tool.
I don't know whether BeerSmith 2 now does or not.

Does anyone have a table as to the % shrinkage of wort at various temperatures between say 20C and 100C ?

No table but the industry norm is 4%. Simply build that in to your overall "loss" factor along with trub, ullages etc.

Wes

 

[warra48]

No table but the industry norm is 4%. Simply build that in to your overall "loss" factor along with trub, ullages etc.

Wes

Thanks for that.
I'm still wondering if the shrinkage is linear between the 2 temperatures I mentioned.

 

[seemax]

Doesn't Beersmith have a cooling factor (%) ?