44. What is meant by a "fully activated" starter?
You want to mix your dough when your starter (or sponge) is fully activated.
I'd suggest that you take a few days and get to know your starter and its cycles. You might want to find some sort of container that you can mark - either with a pen or a piece of tape or you can tape a strip of paper vertically on the container and use that. Glass canning jars work well and you can easily see into them, or anything else that's straight-sided (easier to judge volume increases than flared-sided containers, like most bowls).
Take a little starter and feed it, in whatever ratio of starter to new food you intend to use regularly (I tend to use 1 oz starter and add 6 oz combined flour and water (or even 4 oz combined water and flour if I'm going to be doing a number of feeding cycle), but use what you are comfortable with). Feed the starter and then just watch it. Every hour mark the container as to the level of the starter. Check it after 12 hours. If it's started to separate and form hooch, feed it again. If not, leave it for another 12 hours.
Next time you feed it, discard most of the starter (or use it bake with or to build a sponge) and add your water and flour (I do the same as I described above, discard down to 1 oz, add water & flour. I add equal amounts of water and flour by weight, not by volume (I just find it easier, and I always know how much of an amount of starter is water and how much is flour). This gives me a pretty thick starter, which is my preference).
The cycle of a starter after being fed and left to sit out at room temp is: - for a while, it looks like nothing is happening - then you will notice small bubbles beginning to form - the volume will start to increase - this will go on for some time, with more and more bubbling and increasing in volume - eventually, the starter will be fully activated. At this point, it should be full of bubbles which are well-integrated throughout the starter (not just on top) and it may have a layer of foam or froth on the very top. If you starter is a very thin consistency, you may instead have a couple of inches of foam on the top and not so much bubbling within the starter. If your starter is thick enough, it will have at least doubled in volume. This is called the starter's "Peak". - it will stay at this level for a some amount of time. - eventually the starter will sort of fall back into itself, the volume will drop and the bubbling will decrease. - at some point later, the starter will have evened out, no bubbling will be present, and the starter will be a calm, thin batter sitting in the bottom of your container. - eventually, it will begin to separate and form hooch.
It's my understanding that peak yeast activity occurs while the starter is plateauing or just starting to fall back into itself, and that this is the optimum time to use the starter.
How long a cycle takes depends on several things: - the starter itself, and the mix of organisms in the starter - the consistency of the starter (thick ones take longer than thin ones) - the temperature at which the starter is sitting (as well as the temp the starter was when you began and the temp of the water & flour used) - possibly your altitude (slower at high altitudes) But as a general rule, a cycle takes 8 - 12 hours but some starters, like SDI's Russian Starter, are much faster than that.
So, my suggestion is that you put your starter through some feeding cycles and pay attention to what it does. Not that you need to watch it every minute, but check on it every hour or so and mark it's level, or keep notes of the time and what the starter looks like. Then you can play around with activating it at different temperatures or different consistencies and see how that change affects it.
If you do this, you'll really get to know your starter. You'll know what it looks like when it's fully activated (at it's peak), or where it is in its cycle, and how long everything takes. This will give you a much better handle on baking with the starter.
One thing you'll notice as you read some of the sourdough literature is that there are discrepencies and variances with just about every aspect of starter maintenance and baking procedures. Keep in mind that there is no one, true way when it comes to sourdough. The stuff is so flexible, adaptable and variable, that all kinds of procedures and methods work with it. The trick is to experiment and find out what works for you, with your starter, in your environment. It takes a bit of experimentation to find that for yourself, though. Keep talkin' and keep readin', you'll come across lots of people's ideas that you can try out.
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