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Baking 90 Count Potatoes For 250 People

Q:

I read your article about cooking large quantities of baked potatoes and putting them in a cooler to keep them hot. We do a fish dinner every year during Lent and cook about 250 potatoes a week for 6 weeks.  Do you have any data on how long it takes for the baked potatoes to reach 185 degrees F? We wrap (I know, I know) the potatoes and put about 30-35 potatoes on a full size sheet pan. We put in two racks per oven. Normally we set the commercial gas oven to 500 degrees F. Is it better to cook them at 400 degrees F?

A:

The time it takes for baking really varies based on the actual temperature calibration of each individual oven (sometimes if you call the power company they will come out to measure and adjust to get accurate temperatures versus what the dial says, often doing this for free) and the size of the potatoes maters as well, but usually 1 hour at 400 degrees. Larger potatoes take longer.

Do you know what carton count size you are ordering or how many fifty pound cartons for the 250 servings?

Cost and Size Guide  

I would recommend the 400 degrees F rather than 500, especially if baked in foil. The higher the temperature, the faster the outer bottom of the potato cooks and turns brown by the time the inside middle is done. A lower temperature allows for more even cooking. One really good method is to bake the potatoes without foil, remove each with an oven mitt and then wrap in foil to retain the heat. The potato is about 80% water so not baking in foil allows the steam to escape.

Q. Here are a few more details. I have a Fluke Multimeter and we calibrate the oven every year so that we know the oven measures are correct so far. We measure at 400 degrees F. It's a brand new oven only three years old. Both ovens measure the same. The potatoes we use are 90 count. We get 3 boxes of potatoes each week. Depending on what the wholesale vendor sends us, we do throw some out. This is usually the problem every week. Any tricks to tell the vendor to supply us with fresh potatoes? And the reason we don't wrap the potatoes after baking is because we work out of a very small kitchen and doing that operation after baking would slow us down too much. We have to turn right around and start baking the haddock. Suggesting 400 degrees F rather than 500 degree F is a good tip. Is the one hour you mentioned to reach 185 degrees F or 210 degrees F? We need to conserve time. Putting the potatoes in a cooler really worked out great. They kept HOT, not warm for a few hours.

A. Good information. One hour should reach 185 degree F, the potatoes will continue to cook when you pull out. 210 degrees F is fully cooked, ready to serve. As a fail check, pierce with a fork at the one hour time interval. 90 counts should cook within that time, not very large. As for the age of the potatoes… Idaho® potato cartons have a stencil marking on the side with the Julian dates, so you could have them check before sending to you. It also states the shipper by number and the variety, such as Russet Burbank or Norkotah.

Current Julian Dates

Shed ID Numbers