Washing machine controlled by Arduino for homebrewing
There is an article by Atmel, talking exactly about this (not for homebrewing, though). They provide a link to a PDF file that describe in detail a project involving Arduino and a re-created washing machine.

Note that it seems to be some kind of Bachelor graduation project, and that the students seem to build an entire washing machine. They control the rotor using an Arduino, and even provide the code (and a brief history about washing machines..).

Apart from building the entire machine, there are two main directions here as I see it:


Manipulate the existing washing machine's control board using Arduino. The bad news are the it would require some reverse engineering of the existing controller, because, per my understanding (and I'm not an expert on the subject) there is no one standard and any manufacturer seems to use it's own propriety control board (similar to Microwaves or Dishwashers). The good news are that an expert could probably do it, either by dumping the controller memory and examining the hex code or by using JTag. 
Another way to go here is interfacing the electrical hardware itself; see this instructable where the guy connected the Arduino in parallel to the start button, by thus allowing an alternative way to start. 


As for a beginner, it would make more sense to go for the latter; in-parallel connection with an existing hardware button should be a fairly comprehensible task. Consider the hazards of working with a high voltage/power device such as washing machines. I must say that on first glance such a project doesn't seem fit a novice, but I would be the last one to hold an enthusiast's back. And if you know any, I would suggest asking supervision from someone with a strong EE background.