Enter the hamster cage.

What is the meaning of ‘Enter the hamster cage.’ in this context?

…If you take it out just after forty eight hours, guess who re-appears, our wee friend Malty. So if you’re wanting to make a malty or a nutty, spicy style of single malt Whisky, you’re going to have cloudy malt and you’re going to have short fermentation. ** Enter the hamster cage. **If however you want to make a different style of Whisky, a style with more flora aspects or more fruity aspects you’re going to be leaving the fermentation to run on for longer maybe as up to as much as one hundred hours…

Thank you.

I took it to mean it would not be good to drink; that is, fit for the hamsters only…

Sounds to me like a not-particularly-menacing version of Thunderdome.
Two men enter. Eventually, two men leave.

Does it mean

Doing the same thing over and over in short period of time.