The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Make shift proofing box

Faith in Virginia's picture
Faith in Virginia

Make shift proofing box

My house is so cold!

How cold is it?

My house is so cold I open the refrigerator to get warm.

I'm almost's been around 55 at the warm part of the day and much colder at night the thermostats are set to 40.
So I need a proofing box. I found a great idea online and I don't remember where. This proofing box uses and empty oven with a light bulb and a dimmer switch to adjust the temperature.

I started off with a 100 w bulb. I cranked it wide open for 3 hours and got the temp up to 75. So the 100w got me 20 above ambient room temp. I just got some new sourdoughs and it recommends to start off at 90. Simple enough the 300w bulb got that extra I need.

I just wanted to share this idea works well. Adjusting the temperature is like getting the wood smoker temperature adjusted...up some ...down some...up some. I thought of using a thermostat but that has so many variables and other issues...all on...all off...all on...all off.

I bought all the parts for under $20

Hope the helps

ehanner's picture

A few of us have used an ice chest with a light to proof in. At the temperatures you describe I think I might consider fermenting in a Ziploc bag with the dough tucked in an inside pocket in my winter coat.


Janknitz's picture

I have visions of "proofing nests"--we can sit on our starter ;o)

90 degrees sounds a bit too warm IMHO.  It might encourage growth of some of the nasty bacterias.  Most things I have read suggest 70 to 80 degrees F. 

I put a cup of just boiled water next to my starter or dough and turn a styrofoam cooler over the whole thing.  This will remain about 80 degrees for a long time.  It also works to use the microwave as a proofing box with a cup of just boiled water for heat. 

ehanner's picture

My son and his roomy's while he was at college kept the thermostat at 50F which I think is as low as they go. They all had sleeping bags and heating blankets. They told me they were establishing the proper temp for a large walk in cooler. They wouldn't spend a dime on heat if it would cut back on the craft beer budget. Kids.


shuttervector's picture

I have used my microwave with a measuring cup of boiling water. Put the dough in a container and put the measuring cup in and shut the door of the microwave. Keep it that way for as long as you need. You could put an instant read thermometer in I suppose.

Dorothy, shuttervector

Faith in Virginia's picture
Faith in Virginia

The instructions to activate the dry culture recommend to start the proof at close to 90.

"The higher temperature promotes growth of the lactobacilli and acid production. High acidity prevents contamination by non-sourdough organisms present in all flour." (Sourdoughs International)

While playing with my proofing box in my frigid house I made up a Poolish popped in the proofing box for 2 hours at 90 then 4 hours at 70 to ferment. The aroma was the best I have made yet. I made Ciabatta Bread so the oven size proofing box was great for all my fermenting stages. So nice not to sit and watch this cold lump of dough thinking will it ever rise.

I thought about using the hot water in a box but for me starting sourdoughs and the long fermenting stages would require many water changes. I'm not worried about the electrical usage, my "easy bake oven" won't use near the electrical power as trying to keep the house warm. Last night the house felt warmer perhaps it was from running the easy bake all day and the bread baking. None the less the proofing box really improved my bread.

Gourmand2go's picture

I've used my kitchen sink as a convenient proofing box by putting my bowl of dough in the sink next to a teapot full of hot tap water.  I cover the sink with a cutting board and place a towel on top to keep the heat in, and it creates a warm humid environment for the yeast.

It's a handy short-term solution.

Experimental Baker's picture
Experimental Baker

what ive been doing to proof my bread is sticking it over a bowl of hot water and putting it in the microwave.  it doesnt take up the oven so i can preheat and stick it right in. 

it worked fine with my small batches of one large boule or two small batards but doesnt work well with double the recipe.  its too big for my small microwave.  thatll teach me!