Delayed Fermentation - how has it worked for you?

I have used delayed (cold) fermentation for a few breads. I think there are three  effects: With sourdough breads, it seems to make them more sour. It has complex effects on the crust of all breads. It seems to make a sweeter crust with a darker, reddish color and little blisters under the surface. With some breads, like Hamelman's Multi-grain levain, it results in a more intensely flavored crumb that I can't really describe, since it is so complex.  Some one who knows more about bread chemistry than I might be able to provide a more scientific explanation. I just know that both yeast and lactobaccili do different things to whatever they are eating at different temperatures and pH's.  Hamelman in particular makes a point of saying whether or not each levain bread for which he provides a formula "benefits from cold fermentation" or not. Why do some breads "benefit" and others do not?
David

   If you use a delayed fermentation, the yeast becomes dormant and gives acids a chance to develop. Between 35-45 deg. F acetic acids develop best, eating off the complex sugars in the flour. Between 45-55 deg. F , lactic acids develop best. They also develop flavor from the sugars, but are considered blander. I almost always use a delayed fermentation to a degree. some breads, like foccacia and ciabatta, don't seem to improve much. My last batch of bread I made was a sourdough wheat/rye mix that I let ferment for a week in the fridge. My family seems to think it was one of my best breads so far. There are also nutritional benefits to delayed fermentation as well, especially with whole grain breads. The acids break down some of the compounds making them more digestible. Back to flavor. With a quick rise bread most of the flavor will come from the yeast. It's a bold up front flavor which many people enjoy. Not many other compounds get to develop, but it's what a lot of people like. With delayed fermentations, more subtle flavors are in the dough and the taste seems to linger. It's also a little chewier and tends to keep better. Many breads actually improve with flavor over a few days. They don't tend to be real good straight out of the oven and rye breads can be down right horrible. So, for instant gratification, a good straight yeasted bread is probably best. for more subtleties, sourdoughs or cold fermented is the choice.

I use a slow fermentation with less yeast - more to get the bread to fit my schedule instead of the other way around. I'm probably going to redo a recipe on saturday that took 2 days from start to finish the first time and speed it up to a few hours and see if there is a difference.

I have pretty much totally gone to cold, delayed fermentation ever since I attended Peter Reinhart's lecture at The Asheville Artisan Bread Festival in March.  I checked, and that was 34 loaves ago.  As HogieWan mentioned, one the best benefits is in scheduling flexibility. 

My schedule runs pretty much like this: Day 1-refresh starter at 2:00ish, and at 10:00ish Day 2- Mix, perform 4 S&Fs @ 10 minute intervals, scale to loaf sizes, and move straight to a 38 degree fridge.

Bake days are on Day 4, 5, or 6...whichever is most convenient. Not an odious amount of work on any given day, but enough to be Zen like.

My wife and I both feel day 5 or 6 produces the tastiest bread, but all are excellent.  Life is good!

I've been experimenting with long fermentation too. I've been baking only with sourdough starter for a while, and frankly, I do not like the extra sourness that comes with this method. If timing were not an issue, I wouldn't do it.

Murvet