Dispensing with mixed gas

[jasonaustin]

I've only got room in the gas cupboard next to my fridge for a single cylinder, so when I have stouts on tap that I want to 'carbonate' and dispense with mixed gas I have been using Widget World cylinders. This has been ok; you can't quite get the pressure (35psi) really required for a 'guiness-like' head and you do need to manually top up the gas after each pint.
I was passing the Andover Patio Centre on my way back from a business meeting on the south coast and when I got home I discovered a proper mixed gas cylinder in the boot . I'm thinking of replacing the CO2 cylinder with this one and using it to not only force-carb and dispense the stouts, but also to dispense the regular ales. Obviously I will need a secondary regulator to allow me to set a much lower 'dispense only' pressure on the ale corny, but does anyone know if this will work? Should I expect the 'feel' of the ales to change, bearing in mind that I'm not force-carbonating with the mixed gas - just dispensing? But I'm worried that because there's only 30% CO2 in the mix that this somehow means something is going to happen to my beer that is carbonated with purely CO2 (usually naturally, before it's put into the fridge). Any gas experts out there? Cheers.

[steve_flack]

You'll also need a mixed gas regulator as the CO2 ones don't fit the mixed gas cylinders - IIRC the pressure is much higher in a mixed gas cyclinder.

I would expect the flavour of the ales to change over time as gases in solution equilibrate.

[jasonaustin]

You'll also need a mixed gas regulator as the CO2 ones don't fit the mixed gas cylinders - IIRC the pressure is much higher in a mixed gas cyclinder.

I got one of these a long time ago - you know, just in case

[RabMaxwell]

Used 70/30 gas for years i have mixed gas reg & 2 secondaries. When cornies filled with stout i hook them up with the gas at 50- 60psi for a couple of days.Nitrogen really needs to be forced in.When serving i set at 30-35 psi but have found you need to check your lines ect more regularly.The higher pressures makes it more prone for leaks than co2. Cheers

[Frothy]

this is very useful - first stout on the mash today

Matt

[tribs]

My understanding was that you should carb low with CO2 but use mixed gas to dispense as nitrogen has limited solubility.

[jasonaustin]

My understanding was that you should carb low with CO2 but use mixed gas to dispense as nitrogen has limited solubility.

To get a tight, creamy, guiness-like head the stout needs to be flat - ie, no CO2 and then force 'carb' (really 'nitrogenate') at very high pressure to force the low-soluble nitrogen into the beer. If there's no nitrogen in the beer they'll be nothing to be forced out (through a creamer disc say) to form the head. If there's any CO2 in the beer, the head won't be the small bubbled, tight, creamy head you get from nitrogen bubbles that we are after.
AFAIK (it's how I do it at the moment and it works for me)