1 gallon fermentors - actual volume

Hi Brewers,
I am interested in brewing 1 gallon test batches. I have a one gallon plastic food grade bucket and have seen the one gallon glass jugs.

My question is whether these vessels have enough head space for a good primary fermentation of one gallon of wort?

Seems like the actual wort volume would have to be reduced to allow for adequate head space.

Thanks for your thoughts,

Jason

The one gallon mark on those jugs is just above where it starts to narrow. Its more like 1.25 total. A blow off tube is a necessary item for these batches but if you have precise temp control you don't always get any blow off. Once you break the 8% ABV range, your more than likely to get some. I just did a barleywine and even at 58 degrees, I lost some.

Even worse though is when the krausen comes to the top and dries there, you have to break through with your siphon and really damages clarity...its one of the reasons I usually secondary with my 1 gallon brews