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Temp control in a dough raising room

Temp control in a dough raising room

I have a customer with a rising room that they'd like to have at about 68~70F. They spend a great deal to humidify the room with scads of ultrasonic misters to keep the room at about 70% humidity.

Today they told me the room is rising to the 80s and on HOT days low 90s so they were "thinking about running an air conditioner". This horrified me for a couple of reasons. First I can see it sucking all the humidity they just paid to put in the room right back out and down a drain. Secondly you really can't have something as convoluted and maze-like as an evaporator coil in the room as things start growing on the fins... bad things... very bad things... that can break the whole operation by polluting the rising dough.

Their come-back was, "What if we put the air conditioner ahead of the humidifier so the humidifier is fed with the already cooled air?" (Whenever the humidifier runs it pulls external air from a HEPA filter in from outside and blows it thru the humidification unit which exhausts into the rising room.)

That solution was less onerous to me. I couldn't poke any immediate holes in it. The humidifier runs probably about 4 out of 10 minutes.

Got any thoughts, suggestions, gotchas, usual solutions, or warnings about this?

Keith Cress
kcress -

RE: Temp control in a dough raising room

Surely the cold air even humidified to 85% would be a lower humidity at 70F than their 70%?

Suggest you mix the cool dry air with internal air before the humidifier. Starting to get a bit complex. ...

How big is this room?

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RE: Temp control in a dough raising room

Hi Little.

Room is..... about.. 5~600sqft. It has swinging doors every inch of two sides with marginal draft protection as I can see 1/8" gaps around the doors in many places.


Starting to get a bit complex. ..
Yes. Because using room air full of yeasts ahead of the humidifier means the supply water for the humidifier, which is a lake of water standing above ultrasonic transducers, will be fouled with the yeast. I believe that's why the humidifier is fed with scrubbed external air from outside the facility.

Keith Cress
kcress -

RE: Temp control in a dough raising room

Then maybe mixing with the outside air aiming for 60F air to humidify?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Temp control in a dough raising room

Most large scale proofing is done in a proofing oven. This is normally built like a cooler so racks can be wheeled to allow for raising of the dough. Steam injection can be used for RH% addition. If over temp is an issue, I recommend an application of a hanging refrigeration evaporator with axial fans. We have oversized the units to induce short cycling with continuous fan. Keep CFM as high as you can get it. It’s a high temp box.
The baking industry has industry guidelines on the equipment. We did work for Aryzta and they require all SS wash-down rating of the evaps. Low FPI on coils. I would be very concerned about an application of an ultrasonic RH – bio burden. Normally with a sealed room, proofing will off gas water vapor so the RH addition may be smaller than the calculated need. Proofing cabinets have water trays at the bottom. Your room may have a high infiltration thus the need for large water addition.

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