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Patrick S

Patrick S


Kant spel guud

6 hours ago, rotuts said:

the USDA  numbers are a bit high.  whole egg 60 C ?

 

however  they want to be on the safe side so Im guessing that's the reason for the numbers

 

130.1 F   (  a trad less than 55 C ) will pasteurize anything if you leave it ' in the bath ' long enough, then treat it appropriately 

 

after its ' done '

 

I wonder what a 140 egg is like , has it begun to ' cook ? '  i.e. 60 C ?

 

they do say albumin @ 55.6 C is pasteurized.

 

its also important that the pasteurized egg does not get re-contaminated after its pasteurized :

 

i.e. you can't put it back in the egg carton unless its also pasteurized  

 

The USDA guidelines are indeed high in that they are designed to achieve a level of reduction in pathogenic organisms that is sufficient to prevent foodborne illness even in vulnerable people. The target is something like a 5-log reduction in the case of egg products, meaning that the conditions in their guidelines are designed to reduce microorganisms in the product by a factor of 100,000. And it is true that above a certain minimum temperature you can achieve an equivalent log reduction by increasing the amount of time-at-temp, but it's worth pointing out that as the temp decreases, the time-at-temp required increases logarithmically. For instance, USDA recommends cooking chicken to 165F, which hits the reduction target in a matter of seconds. You can achieve the same reduction at 136F, but that would take over an hour. 

 

Finally, a whole egg at 140F will just begin to see some protein coagulation. Ovotransferrin, a protein component that makes up 12% of the white, will start to coagulate at 140F. Ovalbumin, which comprises 54% of the white, starts to coagulate at 180F. Yolk proteins don't start to coagulate until right around 149F (65C), so pasteurizing at 63.3C should not result in any appreciable thickening. 

Patrick S

Patrick S

4 hours ago, rotuts said:

the USDA  numbers are a bit high.  whole egg 60 C ?

 

however  they want to be on the safe side so Im guessing that's the reason for the numbers

 

130.1 F   (  a trad less than 55 C ) will pasteurize anything if you leave it ' in the bath ' long enough, then treat it appropriately 

 

after its ' done '

 

I wonder what a 140 egg is like , has it begun to ' cook ? '  i.e. 60 C ?

 

they do say albumin @ 55.6 C is pasteurized.

 

its also important that the pasteurized egg does not get re-contaminated after its pasteurized :

 

i.e. you can't put it back in the egg carton unless its also pasteurized  

 

The USDA guidelines are indeed high in that they are designed to achieve a very specific level of reduction in pathogenic organisms that is sufficient to prevent foodborne illness even in vulnerable people. The target is something like a 5-log reduction in the case of eggs products, meaning that the conditions in their guidelines are designed to reduce microorganisms in the product by a factor of 100,000. And it is true that above a certain minimum temperature you can achieve an equivalent log reduction by increasing the amount of time-at-temp, but it's worth pointing our that as the temp decreases, the time-at-temp required increases logarithmically. For instance, USDA recommends cooking chicken to 165F, which hits the reduction target in a matter of seconds. You can achieve the same reduction at 136F, but that would take over an hour. 

 

Finally, a whole egg at 140F will just begin to see some protein coagulation. Ovotransferrin, a protein component that makes up 12% of the white, will start to coagulate at 140F. Ovalbumin, which comprises 54% of the white, starts to coagulate at 180F. Yolk proteins don't start to coagulate until right around 149F (65C), so pasteurizing at 63.3C should not result in any appreciable thickening. 

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