The unofficial start of the summer is this weekend in the U.S. – Memorial day. Folks will be bbqing, cooking out, grilling out, whatever.

There’s a recommendation from USDA that on a hot day, above 90F/32C that food shouldn’t sit out for more than an hour. I couldn’t find a good reference for this. So I started texting Don.

He wasn’t answering. (I found out later it was because he was doing an interview with CBC, that’s a radio/TV network in Canada).

I started looking at a Conference for Food Protection document on how to handle food decisions at retail when the power goes out. Not exactly what I was looking for – all the modeling starts at 41F and doesn’t get as hot as I was looking for.

Then Don finally answered and suggested this paper on Salmonella in cut tomatoes.

Getting warmer.

I finally got into Combase and generated a couple of no-lag growth models for staph (in something like potato salad) and Salmonella. 

The staph model doesn’t go as high as 90F/32C so it’s a bit conservative different. But the Salmonella model shows a 1 log increase in just over an hour.

So yeah, hot days matter.