I am new to sourdough starters and was hoping to get some advice. My starter is 12 days old at the moment and I have been feeding it a 1:1:1 ratio once every 24 hours. This is my second attempt at a sourdough starter.
A couple of days ago, I started a second jar with the discard because I felt the first jar was getting a bit messy (dough on the edges etc). However, today when I got home, I noticed what might be a slight pink streak (picture below)? I know this is a sign of mold and so I was a little discouraged since I paid extra attention to hygiene this time around given that my first attempt almost definitely experienced that pink streak/mold. So, I have 2 main questions to start with:
Does temperature severely affect the starter? I’m not sure if it’s related but today is the first day my starter stayed at home without the A/C on at 24C while I was at school (and then found the starter looking like below). I live in Brisbane, Australia and currently it ranges from 30 in the day to 20 at night, with moderate-high humidity. Is it bad for my starter to go through such a range of temperatures or am I overthinking it?
Is feeding it once every 24h enough or should I be increasing the feeds and/or feeding it with a different ratio if we take the higher temperatures in my city into account?
If your starter is bubbling up within 12 hours of being fed then it should be fed twice a day and/or at a higher ratio.
I see a bit of discolouration and while reddish/pinkish mould is something to be very wary of i’m not sure if this is just the property of the flour. It doesn’t look mouldy as such but don’t want to advise it’s perfectly ok if there is even a small chance of it being mould of this sort.
Like Abe I’ve always read that orange/red/pink discolouration could be a very bad mold. I would suggest starting again and not using any of that particular starter.
Good to know about the frequency and ratio. I did find my starter to be doubling up + bubbling within 12 hours but still went with 1:1:1 once a day. Oops. I have a second jar of it which was much less questionable but still unsure - will see how it goes and may start again.
As for my question regarding the temperatures, it’s probably one of my main concerns as I couldn’t find much info on it. Is it okay to stop worrying about the day-to-day fluctuations (30C in day, 20C in night)? Or should it be temperature controlled at 24C (proofing box or A/C)?
The temperature range your starter is experiencing won’t have any negative effects. At the lower part of the range fermentation will just be slower than at the higher end of the range. However, the microbes will be just fine in the whole of that range.
Benny
As Benny said… it’ll slow down when colder and speed up when warmer. As long as you’re keeping it healthy by feeding it when it needs to be fed then it’ll be fine. If you find your starter is maturing too fast then either incorporate fridge time or feed it more flour or lower the hydration.
1:1:1 is an ok feed but if you have a strong starter then it’ll benefit from a better feed. It’ll be difficult to keep on top of 1:1:1 feeds.
Once you have made a starter, it’s strong and functioning well then keeping it at room temperature is not ideal unless you’re baking everyday.
Understood! Really appreciate the reassurance about the temperature—a big sigh of relief. And yes I do plan to move it to the fridge with once a week feedings after it’s nice and strong, just need to get there first. @Abe - by a “better feed” do you mean for example a 1:2:2 ratio?
In terms of mould/other unwanted microbes, will my starter still rise in the presence of them? For example, I fed the second jar (not the picture above) and it had a good rise (2x) overnight—would this still happen if there were actually unwanted bugs?
I have one last one question for now. As opposed to temperature, are there any detrimental effects of higher than normal humidity levels? I believe it’s hovering around 85% right now where I am and presumably worse indoors.
Both of my attempts have now resulted in the same pink streak microbe. It seems like there are 2 common denominators—one being the 1:1:1 once a day feeds that weren’t enough, and the other possibly being humidity/heat. If you don’t believe the latter is a major contributor, I will go ahead and focus on increasing my feeding frequency.
Healthier feeds are good for when the starter has matured. Until then 1:1:1 or even 2:1:1 is fine and even beneficial. This helps encourages the pH of the starter to lower while still feeding the microbes. However once it is predictable and strong it is then beneficial to increase the feeds to keep it healthy. Either that or keep on top of the feeds giving it fresh water and flour whenever it peaks or store in the fridge. What is also beneficial is to swap the water for pure pineapple juice (vitamin C is fine but no preservatives) until you’re getting a strong ferment then switch to water. And just in case of cross contamination make sure you clean and sterilise the jar or use a new one (also cleaned and sterilised of course).
While this method doesn’t include pineapple juice it is good. I tried it and got a good starter going relatively quickly…
The only major effect of humidity is if your flour has absorbed some of that humidity and thus the thickness of your starter may be more on the batter side than in a drier environment. I use a humidified proofing box to ferment my dough in and ferment my starter or levains and have never had a problem.
Hi. I am Diane , Dennis’ wife. I have been reading about the pinkish orange mold problem with the sourdough starter. Sorry for the late timing.
I think it is a pathogen called Serratia marcescens. It is not a good one and is capable of causing illness. Hopefully by now it is resolved as last post was 12 days ago. ('by starting fresh with clean sterilized jar, surfaces and utensils ). Serratia florishes in warm humid conditions and it is pink reddish orange in colorations. There are specific places where this bacteria may grow. It is harmful please never use starter or dough if it is present.
Hope this helps. Diane
Thank you Diane. I’ve always been aware that one should be very wary of this mould. My advice has always been never to take chances if it is red or pinkish. However i’m no microbiologist. Thank you for the more in-depth explanation why it is necessary to be so cautious.
