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sourdough starter smells bad

jjeisse's picture

sourdough starter smells bad

My sourdough starter of 3 months went bad so I had to start a new one.

I've had what I think is 3 failed batches of sourdough starters. 

The temperature in my kitchen is between 27 - 29 °C. The flour I use for my starter is Bob's red mill whole wheat flour.

I followed two different starter recipes.

The first one was based on Ken Forkish's recipe - 150-gram whole wheat flour and 150 gram of water (32 °C), throw three-quarters of the initial mix on day 2 and feed 150 grams of whole wheat and 150 grams of water. 

The first batch had a pale-colored layer at the top and smelled foul on day 3 so I threw it out and made a new batch. The 2nd batch had orange patches on the top and smelled off on day 2.

For my 3rd batch, I tried a different recipe, I used 50 grams of whole wheat flour and 62.5 grams of water. When I checked on the starter the next day, there was fermentation activity and it expanded but there was a layer of liquid at the bottom of the jar and there was a funky smell.

I've not experienced all these bad smells from my previous starter. 

I don't know what I'm doing wrong. Should I feed my starter more often? or is the temperature in my kitchen too warm?

3 Olives's picture
3 Olives

I would increase the number of feedings, the ratio of flour and water to starter, or both. 

ciabatta's picture

it's not unusual to have weird smell or off color growth in the first week.  just toss the top layer when you feed.
we want to refine the culture in the starter to be the good bacteria and yeast. but starting off, you're going to have some bad stuff in there.  as the environment gets more acidic, the good stuff will take over and the bad bugs will dwindle with each feed.   when using whole grain, likely the bacteria and yeast is coming from the flour itself. so you might see similar results with the same flour.  look up the pineapple juice method to help it get going early with an acidic environment.  In a warm environment i think every 8-12 hours is good. make sure to give them enough time to grow, so not too often. It'll be easier to judge on when to feed when there's more gas producing activities.

Mr Immortal's picture
Mr Immortal

The pineapple juice method that Ciabatta mentions is a set of articles by Debra Wink, which is a fantastic read if you are interested in an in-depth look into what  exactly is happening in your starter in those first few days/weeks.  The bacteria that take up residence in the first few days are some pretty unpleasant things.  But, while they could potentially make you pretty sick, they are performing a valuable function in your starter:  they are consuming starches and simple sugars, and creating various acids as by-products.  This acidification paves the way for other more acid-loving bacteria, who’s bodily functions continue to further acidify their environment.  In a few days, the starter has become acidic enough that the initial “foul odor” bacteria can no longer survive.  Eventually, the whole mix becomes acidic enough for wild yeasts to be able to come out of dormancy, and a starter is born!


FoodHacker's picture

I used apple cider vinegar in my starter ... of course the problem is it smells like vinegar, I have done the pineapple starter years ago and I thought it worked great ... what I'm wondering is could apple juice be used instead ... I'm really not liking the vinegary smell my current starter has

phaz's picture

I believe the main thing is the acid. You could most likely find the ph of pineapple juice somewhere and find something else that's close enough. You might have to factor in buffering capacity, but if you get close with ph I'd bet you'd be good. Ascorbic acid would work, and is used as a dough conditioner. I just made a new starter with cheap unbleached white flour, oatmeal (Quaker from the box), a couple red raspberries from the golf course and I think the acid from the berries was enough. It was doubling on the 3rd day. That was yesterday and it's 3-4x today. 

jjeisse's picture

Thank you for your suggestions!

I've increased the feeding and it still smells a little funky but not as bad. I will also check out the pineapple juice method!

Mr Immortal's picture
Mr Immortal

Keep in mind that while The Pineapple Juice Solution articles have some great information, and offer a very detailed technical explanation of how and why a starter becomes active, the pineapple juice method itself is only helpful if you apply it in the first two or three days of a brand new starter.  Once you are more than three days in, adding pineapple juice will do very little for your starter, if anything at all.


Ultimately, if you just keep feeding it regularly, it should eventually balance itself out.