Hi! I don;t know if non-sour-dough starters are allowed her. I am making active ferment sponge from liquid yeast culture - the current culture is a couple of months old. Everywhere else on this forum, sponge is a pre-ferment. Since mine takes over a day to set, I don't think we are talking about the same thing. I bake about 3 times a week and go through about 40 to 50 lbs of bread flour a month. My sponge gets stuck over 50% of the time and needs to be re-inoculated (pitched). What comes out of the oven is consistant. It has the intended flavor, crust, crumb, and rise. I would just like some help identifying why my sponge keeps getting stuck. Note: it is just as likely to get stuck with active dry yeast as it is with emptins.

Bread Making Equipment.
All of my key bread making tools are of a compatible size and create similar limits as to how much bread can be made at a time.
Oven - ½ sized convection with a 14.5" x 16.5" baking stone. Useful vault height with stone and glider assembly is 8". Manufactured by Dacor.
Stand Mixer - Kitchen Aid 520-Pro. All metal gears, housing, and transmission. Sintered bronze journal bearings. Capacity 5 quarts, 450 watts, with a dough hook.
Peel - 15" x 18" with 12" handle.
Sponge pot - 4 quart, NSF, stainless, with a close fitted lid.
Proofing pot - 8 quart, NSF, stainless, with a close fitted lid.

Sponge construction - best practice.
The goal of this practice is to add "fullness" to the mouth of the bread without the use of sour-dough methods. To avoid the overt sweetness of sucrose (table sugar), I use dry malt extract (mostly maltose and some non-fermentable dexedrines) and a modest addition of sea salt to the dough. Flavor complexity is enhanced by the use of a baker's sponge (poolish) as a ferment. This sponge technique is, most definitely, not a pre-ferment.
Also, unlike typical sponge technique, this sponge provides all the hydration and leavening for the bread. Brewing sanitary methods must be used to prevent molds, wild yeast, and bacteria from gaining a foothold in the ferment. Additionally, this practice borrows significant components from 17th and 18th century baking technique. Consequently, volume, weight, and time measures are very loose. The focus is on temperature, feel, and zymurgy (the care and feeding of yeast). Note: this practice is a lot simpler than that required for the brewing of beer.
To pitch means to add liquid yeast culture to the mix while minimizing thermal and mechanical shock. Barm is yeast infused foam {FYI, the English word "barmy" - meaning a kind of crazy air head - derives from this} . Wort is a liquid growth medium for yeast and bacteria.

1.Sanitize everything and avoid contact with aluminum. Boil and cool the hydration to 80° F.

2.Instant wort - add malt extract powder at 1 part to ~20 of hydration. I use a gallon milk jug to shake the instant wort (aerate) for a few minutes - gets very foamy. Adds O2 which is required by the yeast for propagation - not fermentation, which follows after the oxygen is depleted.

3.Yeast (S. cerevisiae) - preferred source: emptins {see the Wikipedia, Baker's Yeast, History
 Ref. Simmons, Amelia - American Cookery, Hartford, 1798}, or active dry {activate per instructions, but use the instant wort}; Note: if not using emptins, use some ale samplings (draughts extracted from the primary and secondary fementers to taste the progress of the developing ale) in the hydration to fake the flavor.

4.Set aside a cup or so, of the instant wort in the refrigerator to rescue stuck sponge.

5.Transfer the remainder of the instant wort into the sponge pot, pitch, and rest, covered, for 2 to 12 hours to create a barmy liquid yeast culture.

6.Start the sponge - add enough bread flour to create a thin batter (1 part in 2 usually works).

7.Set the sponge - rest, covered, overnight (or longer) at 70° to 75° F. Note: the sponge can be stopped for a couple of days in the refrigerator.

8.Proof the sponge. A fully set sponge is uniformly bubbly, tripled in volume, very sticky, and smells of young ale. If the sponge has separated, it is stuck. This is a highly likely outcome, given the rather variable diastatic potency of the emptins. Don't worry, the yeast have done some very useful work. Use the set aside instant wort to activate more dry or instant yeast and pitch, otherwise just add the set aside. Mix in an appropriate amount of the flour to match the added liquid. Let the sponge rest for a couple of hours and then fold it into dry ingredients of the dough.

My re-innoculated, stuck sponge, made a wonderful batch. I've been working on this recipe for 3 years. This is where I wanted to go. As soon as I can confirm repeatability, I will post my "recipe" - actually it is written as a "best practice".

Had a stuck sponge this time. Fell back to good 'ol "dry active" to re-inoculate and the sponge took off like gang-busters. Will taste the results tommorow while I keg my new Red.

The bread really rose this time. I even noticed "oven spring" which I understand, results from what in brewing is the protease rest (122 F). I expect some conversion (beta glucanase - 104 F) is also involved.

Found some words in the Wikipedia that refer to what I am attempting - barm {from which the English get the word barmy - which may explain the why of my efforts :-} and emptin's (emptings) - an old American cooking term that showed up in print in 1790's (Simmons). The description of emptin's exactly describes what I have been doing.

According to the Wikipedia,  "active dry" was invented for WWII and "instant" was invented in the 1970's.

As to the current state of my recipe - the sponge provides all the yeast and water for the bread. 1 Tbs malt extract powder to each 3/4 cup of water (simulates wort) and 2 parts bread flour to 3 parts water (provides the right consistancy for the sponge). The fake wort is raised to 85 F and shaken in a gallon milk jug to remove chlorine and add oxygen). The yeast is pitched and allowed to rest for an hour or two. Flour is added and allowed to rest overnight.

Re-inoculation method for a stuck sponge is: 1/4 to 1/2 cup water, 1 teaspoon malt extract powder, raised to 105 to 115 F, one packet of "active dry", rest for 15 minutes, pitch it into the stuck sponge and stand back :-)

Assuming the new bread has the flavor I am looking for and given the cost of "active dry" versus the effort to maintain a pure yeast culture, I may drop the yeast culture effort and only use the emptin's on the days I rack (primary and secondary fermenters) - which is at least a couple of times a month.

I've been rumaging arount this site a bit, read reviews of The Village Baker etc. I too, am trying to go back in time - pre Fleishmann's (1860's). Before instant and dry active yeast. I work with my own yeast cultures, but trust me, if something goes wrong, out comes the active dry. It is a wonderful failback.

I make live, cask conditioned, export bitter ales (extra, special, and best). IPA is an export based on either session or ordinary bitter. I grind my own grain, step mash, and dry hop. In this, some of my methods go back to the 18th century (before Louis Pasteure discovered the role of yeast). The same biases show up in my bread making - which is why I try to get all of my baking yeast from poolish. It also means that I fool around with recipies so as to jetison the dependence on modern (the last 150 years) yeast sources.

The really odd thing is, that I avoid a lot of the difficulties I read about on this site. The sponge setting step has a very elastic time scale (6 to 60 hours) - at least the way I go about it. However, once the dough process starts, the assembly line timing takes over until it comes out of the oven. This is very similar to when the strike contacts the grist in the making of beer. The 6 hour process ending with "pitching the yeast" is "in charge" of my life.

A note in passing. I just finished baking a couple of loaves of Italian from yeast culture poolish last night. One loaf has already evaporated (before noon today). I have a very small oven - 1/2 sized convection with stone - 2 loaves max. It would be nice to have a double stack, baker's depth, but then there would be no room for us to live here.

I very much appreciate the efforts made by the members of this forum, both failures and the successes. I really enjoyed "High Altitude Bricks". So many wonderful breads, so little time :-) I hope to try them all.

If anyone has questions about yeast, ask me. If I don't know, I know people who do - and I enjoy the research. Consider me your local zymurgist. Meanwhile, I'll keep plagerizing (the sincerest form of flatery) your recipies and methods.

I am a retired engineer, a baker of bread, and brewer of beer. This blurb is narrowly focused on what I have learned about the setting of sponge for the baking of bread (updated 6.May.09).

I have a very large supply of Saccharomyces cerevisia, the species of yeast used for baking. It is a by product of my brewing of ales. I cannot match the expertise and baking skills I have observed on this forum; but, I can contribute in this fairly narrow aspect.

The strain of S cerevisia is of little importance in baking. If it did, nobody would use instant or active dry yeast. Many students can attest, beer from these sources is not good. The bread turns out fine.

Stainless has no practical effect on yeast fermentation. Stainless steel is the rule for the construction of fermentation vats by both brewers and vintners. Yeast acidify their environment only slightly.

Oils and iodine (as in most table salt) are poisonous to yeast.. Small amounts MgSO4 (Epsom) & CaSO4 (Gypsum) cause no problems. Adding salts, is generally, a very bad idea.

Flour is a second rate food for yeast, they have to be starved into eating it (aclimate). Malt extract (malt liquor) is the finest yeast food. For baking, I recommend a dry malt extract - less than $5 / lb; almost a lifetime supply and it stores in anything airtight.

My understanding is that sponges differ from starters in that yeast propagation is not done with flour. Starters, quickly, get contaminated with wild yeast, molds, and bacteria - most commonly lactobaccilus which creates the sour dough effect. Maintaining a pure yeast culture is beyond the scope of this writing (at the moment). Good sanitary practices can maintain cultures for well over a year.

--- How I do it.

The objective of the following method is to impart a rich, full, and complex flavor to the dough without making it sweet. This is done by the maltose and dexidrines from the malt extract. It is more subtle than what occurs with sucrose, glucose, and fructose. The timing and measures are incredibly sloppy. Yeast can be very forgiving, if treated right. Minimize mechanical shock, thermal shock, light, and invadeing microorganisms.

I make as much sponge as possible. I put all off the dough's water requirement into my sponge.

Step 1 - Sanitize everything. Bleach water once, rinse twice. 1 capfull of bleach to a gallon of water.

Step 2 - Make lots of healthy, happy, well fed, yeast. Combine the water and at least 1 Tbs of malt extract powder for each 6 oz of water into a gallon jug. Temperature should be 75 ~ 85 F. Shake violently for a minute or so, to release the chlorine and to add oxygen (aerate). Decant into a bowl that holds twice the amount of water. I sort of add about 1 Tbs of yeast culture for each cup of water. It doesn't really matter as this is a propogation step, not a fermentation step. Cover and rest for 15 minutes to a couple of hours. The yeast will begin to reproduce very quickly. This is not fermentation, which is an anerobic process. Don't peek - at least not much. The longer this is left, the less maltose will remain and there will be more yeast to feed. You can add more malt extract at any time. The yeast are not as fussy about malt extract feeding schedules as they are about flour feeding schedules.

If using another source of yeast - split the water and follow the package directions. Add the malt powder, etc to the remainder. The source of the S cerevesia (yeast) is completly unimportant.

Step 3 - Make the sponge In a vessel, at least 4 times the amount of water (note: I use a small 2 gallon stainless steel pot with lid). Combine 1 cup of flour for each 12 oz of water - a very thin batter.

Step 4 - Set the sponge. Cover and keep warm 70 - 75 F for at least 6 hours. It can be kept for a couple of days without problems. If all goes well, the sponge will tripple in volume, and it will not separate. A fully set sponge will look uniformly bubbly and be very sticky.