Filling fermenter with water before adding wort

[xenomaniac]

This is an odd question but came to mind when thinking of my first brews.

I understand the whole process of cooling the wort down to 80 degrees Fahrenheit in an ice bath but, would putting cool water in the fermenter first, then poor the wort in the fermenter, finally put the fermenter in an ice bath help the cooling process go faster?

Stupid question but curious.

 

[Yooper]

No.

the reason is pretty simple- it doesn't take that long for 2 gallons of 100 degree wort to cool to 65 degrees in an ice bath.

But it takes a LONG time for 5 gallons of 80 degree wort to cool to 65 degrees!

It has to do with the volume.

It's much faster to cool a smaller volume than a larger volume.

 

[BigFloyd]

No.

the reason is pretty simple- it doesn't take that long for 2 gallons of 100 degree wort to cool to 65 degrees in an ice bath.

But it takes a LONG time for 5 gallons of 80 degree wort to cool to 65 degrees!

It has to do with the volume.

It's much faster to cool a smaller volume than a larger volume.

+1.

Also, the rate of thermal exchange is faster when the temp differential between the two different liquids (ice bath vs. hot wort) is greater.

When using cool buffer/top-off water as you are, it helps to put the water in sanitized jugs and place it in the freezer while brewing. You don't want it frozen, just really cold.

 

[xenomaniac]

Makes sense. Thanks

 

[unionrdr]

This time of year,I fill 6 gallon jugs with spring water at Artisian Springs for 10c per gallon the day before brew day. Then put them in the garage till the next day when I brew. I can chill the wort down to about 75F,then topping off with the ice cold spring water gets it down to about 64F. Great temp for most ale yeasts. Or the WL029 kolsh yeast I'm using now. It's a hybrid that likes 65-69F temp range. Maintain mid 60's to about 68F,& ales seem to come out cleaner flavored.

 

[MikeInMKE]

What uniondr said. I'm still brewing extract, so doing partial boils and topping off the carboy to 5.25G.

A few days before brewday, I take a sanitized 6G carboy to the local grocery store, and fill it and a gallon jug up with RO water. When home, I carefully pour 3.5G from the carboy into a sanitized bottling bucket. I then use the bottling bucket to fill a sanitized 1G jug, with the remaining 2.5G getting dumped into the brew kettle.

The kettle stays inside, but the carboy with 2.5G and the two 1G jugs go out in my near-freezing garage to stay and chill down for brew day.

The carboy has a thermometer on it, so I know how cold it is. And with some simple algebra, I can figure out how far down I need to chill my wort such that when mixed with the chilly water already in the carboy, I will hit my desired pitching temperature within a couple of degrees.

Chilling wort down to 90 degrees, racking onto 40 degree water, and ending up with 65 degree wort takes one hell of a lot less ice and time.