Working on the digital side of the project. Looking to tackle it by combining and tweaking:

1. https://www.wevolver.com/gerrit.niezen/openpump---an-open-source-hardware-syringe-pump/software-design

(would need to translate steps of the stepper motor in an mL amount in the software)

2. http://www.buildlog.net/blog/2011/12/makerslide-camera-slider-control-program/

http://www.buildlog.net/blog/2013/10/camera-slider-controller-shield/

and a UI somewhat like this: http://ejuice.breaktru.com/

then have users enter file downloads that code for flavors.. sort of like a torrent.