Jamil just did a two part episode on Brewstrong (Feb 16th and march 2nd episodes) called Brew jobs, and he specifically mentioned job interview tips. Sounds like you should give it a listen! Good luck with the interview!
Don't bull**** the interviewer.
Don't come across as " I am a home brewer, what do you know".
They make the best beer not you.
Your brewing process is wrong according to Palmer.
If the interviewer is a former home brewer he may think his is now big ****.
Don't be afraid to admit you don't know the answer.
Feel free to ask them to clarify a question - even if you think you have the answer, while they are re-asking, you have time to really consider the question and put together a good answer.
Don't waffle or lie to fill airtime
Ask as many questions as you can
Don't expect to spend time talking about the stuff you are confident in. If they are a good interviewer, they will quickly determine whether you understand a particular subject and move on to something that is a bit less certain. No point in wasting time exploring stuff you clearly know.
If you think you gave perfect answers to every question, you probably didn't get the job - you should leave a time-boxed interview exhausted but frustrated that you didn't say everything you wanted. So, if you think you failed and keep on thinking about stuff you should have said, consider it a good thing!
Let them know you're knowledgeable but don't come off as a know-it-all. They want you to be malleable - this is an entry level position. You need to be open to learning any and everything they might require - even if you already 'know' about it.
They will bring up the physicality of the position - let them know you are expecting very physical labor and willing to work any position if/when needed (i.e. willing to work production kegging beer even though you would rather be on the brewhouse).
And be yourself, they don't want to hire a robot - and if they do then its probably not the best company to be working for. It is craft beer after all!