The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

To cover or not to cover

greatcook's picture

To cover or not to cover

I remember growing a starter over 20 years ago and abandoning the poor thing. Now I am older and wiser and want to make another go of it all. I have been reading these related threads til the wee hours and have yet to find an answer to my remaining question before I get started.
When you are feeding your young starter and it is setting out at room temperature do you cover it in any way? Loosely? With paper towel? Plastic wrap? Or tightly as with a jar lid or a plastic food storage container?
And when the mature starter has been relegated to the refrigerator, is it to be tightly covered (airtight)? Even at periodic feedings? 
I am as in-the-dark about this detail as the starter in a closed fridge! Any advice is greatly appreciated.Thanks. 

Mini Oven's picture
Mini Oven

Interesting. I can only say what I do. My theory is that a starter needs room to expell a little gas and not dry out when standing at room temperature. So, I cover it loosely, sometimes with foil, sometimes plastic wrap and a rubber band.

One time I sealed starter inside a airtight plastic bowl and ev. the lid blew off. If it were glass, it could have shattered sending glass and goo all over the place. I have used glass jars and just set the lids loose on them, works if no-one comes along and tightens them. In the fridge, I like them tightly covered to reduce the amout of contaminants from other containers and odors in the fridge. Either in a zip bag or small plastic bowl with lid.

Leaving an open container standing around invites trouble, either something can fall into it or someone comes along and dumps it not knowing what it is.

Mini O

sitzhaki's picture



I cover my starter with a plastic food wrap. This works for me everytime.

When the feeding and fermantation session is done, I put it in the fridge in a plastic

container with the original plastic cover. 

syllymom's picture

I use a glass jar and just put the lid on loosely but when it goes in the fridge I close it all the way.

Shajen's picture

I've been keeping mine in a Mason jar with a small hole poked in the lid. I've had mine for about three months now and it's worked so far.

Oldcampcook's picture

I keep my starters in old pickle jars with the original lids with one or two very small holes punched in them.

I have two starters that are well over a year old and they work just fine.

When I have them out on the counter feeding them, I usually cover the jars with a kitchen towel to keep out any dust, etc.

My SO knows not to touch my jars!  LOL   and I take the knob off the oven dial when I am proofing IN the oven!  Just in case.

greatcook's picture

Thanks to all who responded. I'm ready to get started now. The "hole in the lid" option seemes to be favored. THANKS!

AnnieT's picture

I use glass jars (bought at the thrift store) with the rubber gasket removed so that any gas can escape. The necks are wide enough for easy cleaning and adding ingredients. A.

suave's picture

I keep mine in plastic jars that delis use.  Apparently the lid is not tight enough to prevent the gases from escaping.

syllymom's picture

I thought plastic was not good for starters since it's acidic it could leach.  I know that stainless steel is a no-no as well because the acid and the steel can react messing with the taste.  Hmm... which also make me wonder about proofing in bowls.  I tend to stick to glass for these reasons. 

How true is this?

goetter's picture

I use HDPE #2 containers that once held Nancy's Yogurt (qv  Yogurt's pretty acidic stuff.  No matter how gamy and horrible my starters get, I figure they're safe in these.

HogieWan's picture

Wine and beer are quite acidic and all professional vintners and brewers use stainless fermenters. 


I am a homebrewer and use plastic, glass and stainless vessals. 

KipperCat's picture

I think the proscription against metal touching sourdough dates to the era before stainless steel.  I don't doubt that tin would corrode when in contact with starter, and leave some nastiness behind in the starter.

LindyD's picture

Ketchup is acidic, but is packaged and sold in plastic bottles. Same for spaghetti and pizza sauces.

I was on a soughdough site last night and read that the alleged stainless steel reaction was a myth.

Whatever, I proof in stainless bowls (or whatever else is handy) and use a stainless whisk to stir my starter with no ill effects.




suave's picture

Typically, this sort of thing is true to the extent of one's belief in it.

zolablue's picture

I think based on these responses there must be a difference between storing a firm starter and a liquid/batter starter since most of you don't seal your container and most use a liquid starter.  So this is only for what I do.


I've always kept my starter in a pint-sized glass jar with the seal and lid screwed on tightly.  I also keep it at room temperature.  I recently revived two months-long stored starters (one almost a year) that had been in plastic Glad and Ziplock containers with their lids sealed - no holes punched.


I use the recipe on this thread and the instructions are to seal the container.  Notice at every step Glezer states to "place in lidded jar and seal," or "seal the container," or "reseal the jar":