The dreaded vacuum

No disasters apparent! With enough experience, I imagine that the initial 48 hours in the fermenter go by with a bit less worry, however, I still get concerned when the fermentation isn't obviously bubbling along after 12 hours.

Paying attention to the basics probably helps too. I freely admit that I am a trifle paranoid with cleaning and sanitization. I may need to get a bit more strict about temperature control too, just for peace of mind.

Here's what I did. I cooled my wort down to about 65ºF, poured it into the fermenter and topped it up to 4.5 gallons, then took a hydrometer reading. It was about 1.075. While making a beer that big would be amusing, I was trying to stick to the recipe, so I diluted that up to 5.0 gallons. However, I had run out of spring water. So I used boiled water. Well, even a 1/2 gallon of 212ºF water heats up 4.5 gallons of 65ºF water. In fact, it went up to 78ºF!

I figured, who cares? The place I put the fermenter in the winter is nearby the window, so it would cool down anyway, right? I didn't have any vodka, so I poured a little of the boiled water into the airlock.

Well, the fermenter has cooled down now. All the way to 73ºF. So it occurs to me that this created a vacuum in the fermenter, since cold air takes up less space than warm air. No big deal, except that the vacuum sucked some of the airlock water into the bucket. And, since the pressure is lower than it started, the fermentation will not be obvious for a while longer: the yeast have to produce more gas than usual before any can escape.

So I imagine fermentation has begun, but I won't know until later.