I set a 1gallon shiraz kit going this afternoon, this is my first wine. I have sealed the demijon with a bung and put an airlock in.
After 4 hours, I have yet to see a single bubble come through the water in the airlock.
Is this usual? How long do I usually wait to see these bubbles? Or any sort of visual confirmation that the fermentation is actually working?
Depends on the yeast, really. Krausen in wine may be thin to nonexistent. Bubbling may be slow. If your installation is not exactly airtight, you may never see a bubble.
I wouldn't expect any signs before 8 hours. Wouldn't worry before 24 to 48 hours (depending on temperature), and wouldn't try to intervene before 3 days. After 3 days, if you still don't see any bubbles in airlock, no tiny bubbles or krausen on surface, and no bubbles when you gently swirl your carboy (small enough for it), then you may start to think if it is working or not. Sadly, only sure way to know is to take gravity readings.
I've had kits that have started fermenting within four hours. I have also had kits that haven't started fermenting until the next day. It all depends on the temperature of the must.
If you don't see anything happening (No airlock activity or krausen) within 3 days then there is a high chance that the yeast hasn't got to work.
If you are a beginner using a kit you probably wont have access to a hydrometer to measure the gravity. I would suggest using a second yeast and if nothing has come from that there may be another factor causing a lack of fermentation such as there being too much sugar.
