Priscilla H. Ballou wrote:

> Scott wrote:
>
>>In article >,
>> "Bob (this one)" > wrote:
>>
>>
>>>You're absolutely wrong. Mayo is bacteriostatic. Commercial mayo isn't
>>>processed beyond making it and putting it in jars. It doesn't have to
>>>be. It's stored for three days so it can kill any critters that may
>>>have populated it. Then it's shipped to stores where it's displayed at
>>>room temp. Because it's safe to do so.
>>
>>Along that line, I've heard that it's better to store the mayo at room
>>temperature for an hour after making it, rather than in the fridge,
>>because it better reduces the chance of bacterial growth.
>>
>>OK, it was Alton Brown:
>>
>><http://www.goodeatsfanpage.com/Season4/Mayo/MayonnaiseTranscript.htm>
>>towards the end of "SCENE 3: The Kitchen"
>
> See, I've never understood this. I would expect putting things right in
> the fridge would cool them off quicker and make them safer sooner. Any
> danger, to my sluggish brain, would be to foods adjacent to the warmer
> food in the fridge. But I've heard repeatedly to let foods cool on the
> counter before putting them in the fridge -- for the sake of their own
> safety. Tis a puzzlement.

Two different criteria going on here.

The mayo has a very low pH and a very low water activity, two
conditions that kill bacteria. Cooling it slows the killing process.
Commercial manufacturers store it at room temp for 3 days before
shipping to retailers for that reason.

Cooling hot foods to refrigerator temps should happen as fast as
possible. Most fridges can handle rather warm foods if not in large
quantity. Otherwise, counter cooling works just fine. The foods are
starting out essentially sterilized. The issue can only be of
additional critters introduced during cooling.

Pastorio