# Time and temp



## lemans (Apr 27, 2017)

So today I did a turkey Breast.. I have so many apps and web sites that have drastically different times and temps that made my head swim.. I have books and articles.. and everyone has a different opinion..
  So I did it at 131!!  Not a temp that anyone would take a turkey to.. usually 160..?but like I told my wife 
141 for 13 hours is fine... and it was.:
   sous vide is on a different level than everything else..


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## SmokinAl (Apr 28, 2017)

This chart that Dave Omak put up helps explain how you can cook at low temps & still be safe.













food safety chart.jpeg



__ SmokinAl
__ Apr 28, 2017






Hope this helps!

Al


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## lemans (Apr 28, 2017)

"Time for 5.0 log reduction " maybe I'm thick!!
What does that mean? In English please..


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## shyzabrau (Apr 28, 2017)

Each log is a reduction to one tenth, and multiple logs are multiplied.

Log reduction - remaining % of pathogens
1 - 10%
2 - 1%
3 - 0.1%
4 - 0.01%
5 - 0.001%

Etc. 

It's a calculated risk!


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## lemans (Apr 28, 2017)

Ok that crystal clear.... Like pea soup...


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## SmokinAl (Apr 28, 2017)

It just means that 86 minutes at 130 is as safe as 1 second at 158.

Al


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## lemans (Apr 28, 2017)

Ok?  Thanx


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## lemans (Apr 28, 2017)

Well 1 sec at 158 is raw.. I I know is that I SV my turkey 5.5 for 13 hours at 130.. it was pinkish and tender. 4 adults ate it. And no one got sick.. so I guess I did good


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## SmokinAl (Apr 28, 2017)

Lemans said:


> Well 1 sec at 158 is raw.. I I know is that I SV my turkey 5.5 for 13 hours at 130.. it was pinkish and tender. 4 adults ate it. And no one got sick.. so I guess I did good


Yes obviously 1 sec at 158 is raw. We are talking about the temp of the meat. If the thickest part of the meat is at 158 for 1 second all bacteria will be killed. Just the same as it would be safe if it was held above 130 for 86 minutes. That is why even if you have chicken above ribs & raw chicken juice drips on the ribs just before you pull them out, it is still safe.

Because the surface of the ribs is above 160 degrees & any bacteria in the juice is killed on contact.

Al


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## daveomak (Apr 28, 2017)

Lemans said:


> "Time for 5.0 log reduction " maybe I'm thick!!
> What does that mean? In English please..


Log reduction...  is a logarithmic function ....    like x² ..  x³  etc.....   

To put it into numbers......

The scientists measure and count bacteria in a given amount of meat...   I have no idea how they do that...   anyway, lets say they measure 500 bacteria in 1,000,000 (million) grams of meat...

A 1 log reduction would be 50 bacteria in that same hunk of meat...  multiply bacteria X 0.1...

a 2 log....... 5 bacteria  multiply bacteria X 0.01

3 log...........0.5 bacteria  multiply bacteria X 0.001

4 log...........0.05 bacteria

5 log...........0.005 bacteria

6 log ..........0.0005 bacteria... 

7 log...........0.00005 bacteria...  multiply bacteria X 0.0000001

In essence, the longer you hold meats, as an example, at a temperature that will kill bacteria, the more bacteria will be killed...  the higher the temperature, the faster the bacteria will be killed...  some bacteria require higher temps to start the killing process....  That's why beef can be safe at 145 ish and poultry can be safe at 165...   different bacteria ...  or something like that...

They also calculate how many bacteria a healthy person can consume and hot become affected...   The body can handle a certain amount...    Persons with compromised immune systems can't handle the amount of bacteria a healthy person can....   those groups include infants, the elderly, the sick.....   etc.... 

So, the FDA, from what I understand, sets levels of bacteria reduction so food is safe for ALL groups...  they don't know who is eating at any food service business....


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## dls1 (Apr 28, 2017)

Lemans said:


> "Time for 5.0 log reduction " maybe I'm thick!!
> What does that mean? In English please..


Following on with what Shyzabrau and DaveOmak have said, “log” stands for logarithm, which is the exponent of 10.  For example, Log 2 represents 10[sup]2[/sup]  or 10 x 10 = 100. Log reduction stands for a 10-fold (or one decimal) or 90% reduction in numbers of live pathogens (contaminants/bacteria/germs). In simple terms, log reduction provides a quantitative measurement describing what percentage of the contaminants which were present when the test began that were killed during the test

Using an assumed known number of 1,000,000 pathogens, a 5 log reduction, such as that shown in the table posted by Al, would result in 10 surviving pathogens following treatment. Each full log reduction represents a 90% kill rate (x .10) “stacked” on top of each other (1,000,000 x .10 x .10 x 10 x .10 x .10 = 10 surviving cells (.001%), or a 99.999% kill rate). A further log reduction to 6 would leave 1 survivor, and a log reduction of 7 would leave, obviously, less than 1.

Since the number of known pathogens present in a test sample is typically unknown, the standard protocol in such tests is to determine what level of lethality is required to kill all but *one*. Under the model commonly used by the USDA/FSIS today, a Log 7 reduction is considered the “Worst Case Scenario”, especially when considering infants, the elderly, and those with compromised immune systems. Following that model, it’s assumed that there would be one surviving cell out of pre-test population of 10,000,000 pathogens.

Another way of looking at it is as follows,

1 log reduction means the number of pathogens is 10 times smaller
2 log reduction means the number of pathogens is 100 times smaller
3 log reduction means the number of pathogens is 1000 times smaller
4 log reduction means the number of pathogens is 10,000 times smaller
5 log reduction means the number of pathogens is 100,000 times smaller
6 log reduction means the number of pathogens is 1,000,000 times smaller
7 log reduction means the number of pathogens is 10,000,000 times smaller


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## lemans (Apr 28, 2017)

Now I got it!!!
Thank you Dave Thank you Al


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## lemans (Apr 28, 2017)

Dis1 you r the man!


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## chilerelleno (Apr 28, 2017)

Aww heck, that got boiled down to where even I understand it. :yahoo:


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