The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

New starter smells like vinegar on day 5

mandarina's picture

New starter smells like vinegar on day 5

Hello fellow bakers! I need a bit of guidance building my sourdough starter. I'm kind of new and I'm not sure what to expect.

*** If you know a thread with the same issue please, by all means, share it! ;) ***

Last Saturday I started to build a starter again using Ken Forkish method (from his book salt yeast water flour). I reduce the amount but I kept the same ratios. This method uses whole wheat flour, not rye and it's a 100% hydration. I started to see activity at the end of day 2. On day 3 it was growing pretty well and it never smelled funky (as I had previously experience on the first days), it always had a very pleasant smell of wet flour and slight smell of beer. So far I was feeding it in the morning just once a day, but on day 4 I had to feed it twice because it was growing very fast and 24h would be too much, (my house is at a temperature of 73-76F).

For the feedings I was taking 20 g of starter and adding 40g of whole wheat flour and 40 g of water.

On day 5 I switched to:

15g of starter + 10g whole wheat +40g bread flour + 50g water. 

It was then when the smell turned to vinegar. And when I went home for lunch I saw that it had grown about x3, so I couldn't wait until the evening to feed it again. So I started to feed it 3 times a day (this was yesterday, day 5), morning (8-9 am), afternoon (3-4pm) and evening (10-11pm). The smell is still there. But I have no idea why. I've read online a lot and everyone has a different opinion lol. 

Possible causes according to the internet:

- Vinegar smells is normal when changing from whole wheat to bread flour

- it occurs when the temperature is not warm enough

- starter was under fed (I didn't see hooch though)


What are your thoughts? 

What would you suggest to fix this? Because the bread will come out too sour and with a strong vinegar taste.


NOTE: A few months ago I tried to build a starter using raisin yeast water, and I threw it away because I couldn't get rid of that vinegary smell. I can't remember but it could've started when I started to add bread flour.


Thanks a lot and sorry for the long post!






Abe's picture
Abe (not verified)

Usual young starter "woes" until the very last note - A few months ago I tried to build a starter using raisin yeast water, and I threw it away because I couldn't get rid of that vinegary smell.

Try an off-shoot starter all the while maintain this one as you have been doing while we figure out what's going on.

  • 5g starter
  • 50g water (either boiled and cooled or bottled)
  • 50g flour (40g bread flour + 10g wholegrain)

A larger feed to try and bring it to normal time range, hoping to out feed whatever is causing this smell and changing the water source to see if that's the problem.

Mini Oven's picture
Mini Oven

Have you tried baking with it yet?  Just a small dough, a 1:2:3 with a pinch of salt.  Doesn't have to be big.  The first time I smelled real bakery sourdough starter it struck me as vInegar like.  Just the other day I recalled the memory to his wife and she laughed so hard apologizing as she recalled how he had "set me up" for that experience.  So perhaps the aroma is new to you?  Wish we could smell some things over the net.  

Maybe there is a stray bacteria and then again, it could be normal.  Set some of the discard starter to the side in a small jar and let it ferment longer without a feeding and see how long it takes to start turning to hooch.  Call it mr hooch, date it and observe it as hours and days roll by. Record any second and third rises in the first day or so and also when it goes completely flat. When it's flat, divide it and continue watching mr hooch for hooch.  Give the takeaway sample a name and feed it. See what it does, campare to your original.

Test some of your current starter.   1:2:3 sd dough.   Weigh some of the peaking starter and double the weight with water.  Then triple the starter weight with some flour.    Let's see, if 50g starter, then 100g water, 150g or so AP flour, and half a teaspoon salt.  Use a little bench flour as needed.  Then let it almost double, deflate, preshape and shape.  If dough is rising more sideways than up, do another gentle shape restoring the loaf form as it proofs. Pop any very large bubbles.  Bake and taste the loaf.  Keep notes on time and temps, aromas etc. and I suggest starting out with bathtemp water for mixing the dough.  


Mini Oven's picture
Mini Oven

Just curious, what determines the decision to feed the starter?  

mandarina's picture

So... I baked with the discards from day 5 and the bread came out really nice. Good crumb, good oven spring and the taste and aroma are not vinegary. It has a pleasant sour kick. During proofing and bulk fermentation I did notice a slight vinegar smell but not too much.

Yesterday I started to increase the amount I feed it because after 6-8 h I did notice a liiiitle bit of hooch on the sides of the container. Now I take 15g of starter, 60 water and 60 flour (15 whole wheat and 45 bread flour). The smells is still there, but I just noticed that if I open the lid the smell goes away. Is it possible that the fermentation produces volatile vinegary products? 

It could be that I'm not familiar with the smell. I use tap water filtered with my brita pitcher. 

Also, how much is the starter supposed to grow? x2, x3, x4?

Thank you guys! I think I'll try to do a side-by-side experiment and see how it goes!

Mini Oven's picture
Mini Oven

so quickly.  I do wonder if the starter has successfully made it thru the bacterial chain of events that lower pH. If you find the aromas closer to wine, or the aroma starts to get on your nerves with time and not smelling pleasant, Start a new starter.   Or you might try not feeding so often letting the starter culture rise and fall back for several hours pushing it into 12 hour feedings.  The temperature of the starter makes a difference.  It is possible to overfeed a starter. 

I find that the x2 x3 x4 growth rise of the starter (amount of trapped gasses) is often related to the amount of flour food.  That is, the more it is fed, the more it tends to rise.  But there are variables, like type of flour, how long the starter was mixed, amount of gluten, hydration and temperature.  Lag time, the time it takes for the organisms to reproduce themselves and build up waste products until they can be noticed, will be longer with larger feedings. 

Right now, it looks like you can bake away to your heart's content.  Congratulations!

franklucido's picture

How to know the exact temperature? I'm a beginner and just learning the basics of bread (I've a small Zojirushi BB-PDC20BA breadmaker).

franklucido's picture

How to know the exact temperature? I'm a beginner and just learning the basics of bread baking (I've a small Zojirushi BB-PDC20BA breadmaker).

Reviews on Flour Water Salt Yeast: The Fundamentals of Artisan Bread and Pizza > essay agency reviews.

Mini Oven's picture
Mini Oven

what's up?

jcope's picture

For a while I kept two starters.  One made with all-purpose white flour.  The other with rye I milled myself.  The rye starter had a strong vinegar smell.  I used the same utensils to mix them when I fed, so there was cross-pollination...  often the white flour starter also smelled like vinegar. 

I wouldn't worry too much about it.  Starter can have many smells.  From not much to stong vinegar to even a sort of paint cleaner, solvent smell.  Not sure how to control the smell, but it never affects the flavor of the bread.  And it's really not something you need to "fix". 

I've treated my starters a lot of different ways...  varying levels of TLC and neglect.  Once you get to know your starter, you'll find it is really quite durable and tolerant.