The Fresh Loaf

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Slight off-smell and (perhaps) orange mold on starter

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jjainschigg's picture
jjainschigg

Slight off-smell and (perhaps) orange mold on starter

I've been cultivating a new starter for about 2.5 months: white with a little rye as a yeast transporter (I've done this before with good results). Had no trouble getting it going. Added a little lemon juice at the beginning to offset leuconostoc infestation. Fed regularly. Tapered off the rye flour. Maintained good activity levels for a while, with rapid doubling. Waited for the 'juvenile starter' acetone-generating tendency to die back. Starter stabilized and developed proper sour/yeasty smell with good activity. Began baking with it. No problems. Loaves delicious, etc. Baking about once a week and feeding daily. Keeping the starter around 80% hydration.

Then the cold weather hit and my kitchen started going through daily temperature convulsions as I fought with myself about whether to turn on the furnace for a couple weeks (temperatures down to around 62 degrees, then up to maybe 68 in the daytime). I could immediately see the slowdown in yeast activity, but I kept baking with the starter and aside from longer (much longer) rise-times, it seemed fine. I was actually quite happy for a while because temperatures were such that I could cold-retard on the counter at night, which seemed to work great: developing the flavor without allowing loaves to become overproofed.

Then something started going off with my starter. I kept feeding it daily (keeping it on the counter in covered container with some holes punched in it). And I wasn't surprised when it stopped doubling in a couple-three hours because the kitchen still gets cold at night (though I've turned on the furnace now, so it gets up to around 68 in the daytime). But I fed it yesterday ... it doubled eventually ... sorta/kinda ... but today, I opened up its container and now can smell a sort of 'off' scent ... still backed by the sour-beery-yeasty smell (which I find delicious) but ... not so delicious. A little bit like ... (sorry to use this word, here, but I know you're all clinically-certified bread professionals) ... vomitus. And there looked to be a very, very slight, almost imperceptible orange-ish sheen on the top.

Looking for advice. Seems to me the cooler temps have slowed the yeast and maybe allowed something other than lactobacillus into a niche. So I've applied some first aid -- spooned off the top layer, poured off half, slung in some white flour, a bit of rye (reinforce the yeast population?) and a little lemon juice to help create a more weirdness-resistant environment for a while (though you would think the lactobacillus would be doing that, no?) And now waiting to see what happens.

In general, my experience with these things is that they're hard to kill once they're stable, so I have hopes of the patient pulling through. Am I crazy?

clazar123's picture
clazar123

You do have some nastiness growing . Carefully brush aside the top growth and carefully take a small amount from the interior/bottom to use as an inoculant in a clean jar. I would wash your hands well before,during and after this and possibly boil the clean jar to reduce the microbial population before using it. Add warm water and flour so you have a thick batter. I don't measure so I can't tell you the ratio but it should be a generous feeding (1:10:10?). Cover with a cloth/paper and keep in a room temp location. Stir several times that day .Meantime, get rid of the "contaminated " jar and starter and wash everything, including hands, well.

24 hours later, do a generous discard and re-feed. Stir several times a day. Keep relatively warm (75-80F, if possible. The top of my refrig works well even in winter). Once it becomes noticeably active, start feeding twice a day-always generously discard. The hope is to discard the bad with the good and hopefully the good will re-produce faster and get rid of the bad. I have had to do this a few times and sometimes it depends on what other cultures are around and sometimes it can be remembering to wash your hands before handling your starter. Remember we are all covered in "culture" and some of your culture may have gotten into the starter and thrived. This method only failed me once-it just kept coming back so I finally discarded that starter and started from scratch. I call it "cheesy" smelling-like old grated parmesan or athletic socks,even. Yuck.

Good luck.

Mini Oven's picture
Mini Oven

More than likely the invasion came when the starter was reduced and fed before the population was ready or ripe.   Keep your feed portions low or starter portions high to fend off the baddies.  IF you have already fed a one to ten ratio, tuck the starter inside your vest pocket and keep it warm.  

Normally when the temps drop, the inoculation amounts go up, in your case to keep the timing, a feed of 1:0.5:0.5 would not be uncommon.  Only when the starter is warm can you use lower ratios of starter to flour.  If the starter is slow, let it rise until it peaks.  Over feeding the starter can make the pH go up too high too long and then invasion is possible.  I would go squeeze a lemon too!

Mini Oven's picture
Mini Oven

is cool at night (and the starter too) feed the starter at the warmest part of the day and then don't feed at night when everything slows down due to temperature.  I don't know what the feeding ratio was for summer but it will now change and look out again in spring when things start to warm up again.  Spring tends to be less of a problem than Autumn.

clazar123's picture
clazar123

Follow her advice and you will get there much faster. She has such a great sense of how it works-I am nowhere near that point,yet. Another learning curve but there is so much information-it takes time to absorb it all.

On thinking about this, my method really just starts a new culture but with a bit of inoculant. My thought when doing this is that you can jumpstart some of the good culture and hopefully "wash out" the bad. The generous discards and higher feeding ratio do not allow much acidity to develop initially and some people (as you posted) use an added acid (lemon or pineapple juice) to create that. I guess I just never did that and have not had much of a problem getting a starter going. I do stir it several times a day. So many ways to get a starter going!

I did assume the starter would be warmer through this and that is important. I believe the lactos like it cooler but isn't the optimal yeast temp 79-82F? I find that the top of my refrigerator is a great warm spot in the kitchen-heat or no heat. The refrigerator coils keep it pretty consistent.

 

 

jjainschigg's picture
jjainschigg

Thanks, everyone who commented! Things seem to be stabilizing with my starter -- it has its regular smell back (yum), is doubling at a good pace, and any trace of orange sheen is gone, at least within the scope of a 24-hour between-feeds cycle. I will keep being meticulous about giving it small feedings (during the warmest part of the day) and keeping it lightly acidulated (probably tapering off gradually), and we'll see where we are by the coming weekend.

Comments from all were hugely helpful. The idea of removing the (possibly infected) surface carefully, grabbing some (likely uninfected, or less-infected) starter from the bottom of the container and using it to re-inoculate the medium was (I think, anyway) a good idea. But Mini-Oven's comment(s) really provided (I think) a good conceptual model for what had gone wrong here and how to fix it: i.e., the infection occurred because I was feeding too much while the starter was at low activity because of temperature, so in effect, offering excess medium to outside organisms that work better at lower (or at a range of) temperatures, letting these interlopers start to establish themselves.

Based on that model, I probably overfed at the beginning of this repair, but may have gotten away with it because I also tossed in some lemon juice. Now that I'm following the 'smaller feedings until established and wait for the warmest part of the cycle to feed' model, the starter is looking (and smelling and acting) much more like its old, aggressive self.

I think I'm going to start keeping this stuff in a foam cooler with a heating-pad on a super-low setting, though, because temperature control in this place is a serious challenge. We just got new appliances and they are all of the 'why would you want a pilot light?' and 'if a refrigerator is warm at the top, it means it's bleeding energy that could be put to good use expanding refrigerants and saving electricity' variety. The only consistently-the-right-temperature place, now, is inside the microwave, when the down-lights are turned on (they're incandescent - a throwback). But the kids have a propensity to use the nuke constantly, so that's not a family-friendly solution.

Again, thanks, everyone. And good luck with the Thanksgiving baking. If anyone needs about 40 lbs of home-made pumpkin puree, y'all let me know. (grin)

 

zoqy71's picture
zoqy71

I've had the same trouble with a white flour starter and have put it down t big temp changes. 25c during the day when the kitchen is in use and 5c at night. Added to this changing humidity. I use the same starter recipe I used in France for a decade without issue, but I now live in the North of England and by the sea.

I now started a 50/50 wholemeal/rye starter which seems much more stable.