Work in progress: Flash pasteurisation/semi-automated brewing

[losjes]

I've been a quite reader for a long time here, gaining a lot of good info! Now I'd like to share my ideas.

As I am an engineer I want full control over my brewing process so I decided to build a semi-automated brewer which should allow me to control every parameter in the brewing process.

Why I want to flash pasteurize
The problem I alway have with brewing cider is that most people find the taste way too dry and quality is different with every batch. Although this is the charme of brewing cider(and any other brew for that sake), most people don't appreciate the dry taste, back sweetening with artificial sweetener or adding chemicals to stop the fermenting process.

Yeah, I know you will say I can bottle ferment and those chemicals don't harm you but I had bad experience with bottle bombs and some people really don't like the chemicals or have an allergy.


First steps
I want to test the idea of flash pasteurisation. Not only from the raw apple juice but also when I think my brew should be bottled. With flash pasteurisation you heat juice for a certain amount of time at a certain temperature and is a continuous process.

This means that I let the juice ferment, force kill the yeast, keg it and put it in a bottle.
It will be a fast and clean setup where I can do a continuous pasteurisation with a speed of 1 to 2 liters a minute.

A lot of calculations have been done and I designed a coil with a certain capacity and it is currently being custom manufactured for me:

This coil will be put in a pot with water. I will be logging the following parameters:
- Inlet temperature
- Outlet temperature
- Halfway temperature
- Heating water temperature
- Flow speed

This way I can fully control the pasteurisation process.

future steps
I think this idea can be fully automated: put raw juice in a container with some yeast and after an amount of time -with one press of a button- bottle it with a perfect balance of sweetness and bubbles.

I even read that it is possible to use the carbon dioxide already present during fermentation so I don't have to keg the brew to get bubbles when I keep a pressure of a few bars in the system during bottling.


I'm no expert (yet anyway) so if you have any thoughts or tips you would like to share, please do so!


I'll try to update this topic with pictures and results!

 

[Pommeau]

I had thought of doing something similar using two coils and two kegs. As I am not good at consistent keeving....

Thought was Run fermented sweet (I prefer Norman ciders) cider from initial keg, through coil immersed in boiling water, then into second coil immersed in ice water straight into the final keg. But using a pressure so the cider was flash pasteurized so as not to affect flavor too much.

Keep us posted on your progress!

 

[Maylar]

Fast pasteurizing I suppose is feasible, though I dunno how it might affect the apple flavors.

You're proposing to stop fermentation before it's naturally completed. Unless you're willing to accept cloudy cider, you should consider a way to filter it too. There's a lot of particulate matter in suspension until the yeasts are done doing their thing.