When's best to use a starter from refrigerator?

Bring it out, let it warm a bit, then refresh it a couple of times before you wish to use it.  If you feed it on a 12 hour schedule, plan your bake accordingly.

You want to use your starter at its peak performance.  No living thing is going to be at peak performance after being stashed in a cold dark place for a few days.

Congrats on creating that starter!

as LindyD mentioned, remove starter from fridge and leave at room temp.

Feed for 2 days, at least 2x per day, keeping at room temp It then should be ready to go. 

I bake sourdough 2 or 3 times per week and keep the starter refrigerated.

I pull my starter (kept at 100% hydration) from the fridge, stir it all up, and let it sit for an hour on the counter.  I then add 12 or 16 oz to my mix depending on how many loaves I'm baking, discard a little and double or quadrupal feed it.  I leave it on the counter for the day and stuff it back in the frige at night until next time I'm baking.

I get a consitant flavor and peformance from it.  It's solid as a rock and doesn't require 4 feeadings over two days. I strongly belive that mature wild yeast is much more durable.  Even better, now that I stretch and fold the dough the bread is better and better.

The thing about my process is that I bake just about every other day so my starter gets a quadrupal feed every other day (some times every third day).  My formula also has a pinch of comercial yeast to tame down the tanginess of the sourdough.

Give it a try, I think you'll be impressed with those little buggers.

My starter gets fed about weekly-- 1x starter: 3x water; 4x flour (a mix of 70% AP, 20% whole wheat, 10% dark rye).  When I'm going to mix dough on Saturday morning, I feed the starter Friday night.  That's it.  The exception is where a formula calls for a special starter build.  I've never had a problem with insufficient starter activity.

Glenn

I think that the yeast and bacteria in a starter adapt to any reasonable feeding regimen. There are lots of methods that will result in very good sourdough bread.

That said, if you want a very specific flavor profile and/or a very specific speed of fermentation, the feeding schedule does matter.

At the SFBI, we compared two breads that differed only in the feeding schedule of the levain. One was fed once per day and the other twice per day. There was a very noticeable difference in the flavors of the breads. The once a day fed levain produced a bread with a more acetic acid flavor. The twice a day fed levain produced a bread with more "balance" between acetic and lactic acid flavors. Our instructor clearly preferred the latter, partly for the balanced flavor, but he also said there was an unpleasant, "metallic" aftertaste to the more acetic bread.

Personally, I liked them both. I couldn't perceive the unpleasant flavor. 

BTW, for those who have Suas' textbook, the "Sourdough Bread with one feeding" is meant to mean "one feeding per day" of the levain.

David

The general idea is to add the starter to the dough when its activity level is near its peak. If you just refrigerated your starter a few days earlier, it's probably fine to just let it warm up and then use it when it's nice and active. If it's been, say, a week, you're probably already planning to feed the starter anyway. Just take the portion you would normally discard, feed it, and keep it on the counter. Plan to mix your dough when the starter should be peaking.

You could also avoid the question completely like I do. I don't bake very frequently, so I don't maintain a lot of starter and don't generally have enough on hand to use in a recipe. When I want to make a loaf of sourdough, I have to build up the amount of starter, so I just take a bit out of the fridge and feed that one or two times without discarding until I have the amount I need.