Jump to content

  • Quick Navigation
Photo
- - - - -

Need help understanding pH results of pasteurised liquid egg


  • You cannot start a new topic
  • Please log in to reply
6 replies to this topic

#1 Irishlass105

Irishlass105

    Grade - AIFSQN

  • IFSQN Associate
  • 44 posts
  • 7 thanks
1
Neutral

  • United Kingdom
    United Kingdom

Posted 05 July 2016 - 01:52 PM

Hi guys,

 

We send a sample to get tested for the pH of pasteurised liquid egg. Our range is 7.2 - 7.9 as this is the advice we received from a 3rd party auditor. Recently, our samples have been below the range and one occasion above the range stated. 

 

My main question is what does this actually mean in terms of food safety if anything? I can find lots of information online about the range but nothing to explain what it means if it is out of spec. I recently contacted the accredited lab who test the egg and they are not able to advice either.

 

I am currently raising the same non conformance and closing them out once they have been retested and if they pass but my bigger issue is whether or not this is a matter of food safety. From research online I am aware the age of the eggs can affect the pH but does this mean our process is failing? or worse our pasteurizing process has failed? 

 

The other tests are based on micro and these are to spec so surely no food safety issue?

 

Any advice or views are welcome.

 

Thanks  :headhurts:


  • 0

#2 brianweber

brianweber

    Grade - SIFSQN

  • IFSQN Senior
  • 292 posts
  • 112 thanks
28
Excellent

  • United States
    United States
  • Gender:Male
  • Location:St. Louis, MO
  • Interests:Golf, Scrabble, Food Safety, HACCP, BBQing

Posted 05 July 2016 - 04:33 PM

I think this site HERE will answer a lot of your questions.


  • 0

Brian


#3 Charles.C

Charles.C

    Grade - FIFSQN

  • IFSQN Moderator
  • 12,462 posts
  • 3246 thanks
347
Excellent

  • Earth
    Earth
  • Gender:Male
  • Interests:SF
    TV
    Movies

Posted 05 July 2016 - 06:49 PM

Hi IrishLass,

 

Not my product area but from google, looks like as per your own finding that the typical (recommended) lethality required for pasteurization assumes a certain pH range.

 

As I read it, lower pH levels of liquid egg may cause increased heat resistance (ie increased resistance to salmonella [et al.] destruction).

 

The significance (if any) of such variations will presumably relate to your specific process conditions / pasteurization methodology.

 

It is usually mandatory to validate the pasteurization process which would involve consideration of such factors, eg for a worst case scenario.

 

There are a few egg experts on this forum who can maybe offer more exact information/guidance.

 

Attached File  liquid egg pasteurization.png   376.97KB   1 downloads


  • 0

Kind Regards,

 

Charles.C


#4 Irishlass105

Irishlass105

    Grade - AIFSQN

  • IFSQN Associate
  • 44 posts
  • 7 thanks
1
Neutral

  • United Kingdom
    United Kingdom

Posted 06 July 2016 - 09:53 AM

What is the pH value of an egg?

The pH of the white and yolk are different and change differently during storage.  The initial pH of yolk is slightly acidic (reported values range from 5.9 to 6.2) and rises slightly during storage to about 6.8.  Egg white pH is initially in the region 7.6 and rises to 8.9 -9.4 after storage due to CO2 loss through the shell.  The natural ratio of egg white to egg yolk in an egg is 2:1 and therefore when mixed together liquid whole egg has a pH range of 7.2 to 7.9.

 

The above is quoted from BEIC website - basically any out of the range means the liquid egg has not been mixed together correctly? Saying that, we keep an additional sample of each sample that goes to the lab for testing and the 2nd batch/sample always comes back fine. We send this to a lab who send it to somebody else for pH testing as they aren't accredited for that test which makes me feel like its a sampling/testing issue not an issue to our process.

 

Could you assume the same or am I wishfully thinking?


  • 0

#5 Charles.C

Charles.C

    Grade - FIFSQN

  • IFSQN Moderator
  • 12,462 posts
  • 3246 thanks
347
Excellent

  • Earth
    Earth
  • Gender:Male
  • Interests:SF
    TV
    Movies

Posted 06 July 2016 - 11:34 AM

Hi Irishlass,

 

Sorry but i am not sufficiently familiar with the/yr process(?) to make  very meaningful comments.

 

As far as lab results are concerned, the typical check procedure is to send duplicate, anonymous, samples to a second lab and compare results. Ideally you include a standard sample whose pH is known but I expect you don't have one ? (Seems rather unusual that a lab.would not be competent to test for pH ?).

 

From a safety POV it presumably comes down to how you validate yr pasteurization stage/justify yr critical limits (eg vis-a-vis pH range), eg -

 

Attached File  egg pasteurizations.pdf   77.23KB   12 downloads

 

PS - just realised i maybe misunderstood yr OP. I thought the pH measurements were made prior to pasteurization. I guess you are receiving the pasteurized product. Would be a different question and safety relate more to specification/ processor's haccp criteria.


  • 0

Kind Regards,

 

Charles.C


Thanked by 1 Member:

#6 Irishlass105

Irishlass105

    Grade - AIFSQN

  • IFSQN Associate
  • 44 posts
  • 7 thanks
1
Neutral

  • United Kingdom
    United Kingdom

Posted 06 July 2016 - 01:01 PM

We pack eggs at our site and break eggs and pasteurize them for bakeries. So no we do not buy or receive the product, it is made in house!

 

The pH range has been set to 7.2 - 7.9 for as many years as I can seem to go back through research. 

 

We validate our process through our lab testing and we use taco charts which are alarmed, these sound when the process hasnt reached the temp for the set amount of time - it has been years since the alarm was last heard as it is never an issue and the pasteurizing machines are only 3 years old and within the last month the taco chart was calibrated. 

 

Once again leaving me to believe it isn't a process issue.

 

Thanks for your response Charles - anybody else got an idea or can help me?


  • 0

#7 Charles.C

Charles.C

    Grade - FIFSQN

  • IFSQN Moderator
  • 12,462 posts
  • 3246 thanks
347
Excellent

  • Earth
    Earth
  • Gender:Male
  • Interests:SF
    TV
    Movies

Posted 06 July 2016 - 04:28 PM

Hi Irishlass,

 

So is the pH range related to the validation of the pasteurization critical limits ?

 

(I would anticipate Yes which would then also be the answer to your OP with respect to the possibility of FS issues)


Edited by Charles.C, 06 July 2016 - 11:58 PM.
expanded

  • 0

Kind Regards,

 

Charles.C


#8 Irishlass105

Irishlass105

    Grade - AIFSQN

  • IFSQN Associate
  • 44 posts
  • 7 thanks
1
Neutral

  • United Kingdom
    United Kingdom

Posted 07 July 2016 - 09:27 AM

Yes - our taco chart verifies the process and our lab results validate them.

 

Before starting my role there were questions asked about the labs ability. As there were questions, the factory manager sent false swabs in. He washed hands, put gloves on and popped the swabs into a bag without swabbing anything and they came back over the count. 

 

I am going to send the sample to our usual lab and I have been able to source another accredited lab which I will send the exact same sample to see if there is any difference in the results.

 

In reality, I feel like this sounds worse than it is as in it isnt a process fail, its an issue we seem to be having with the sampling at the lab. I dont want to be raising CCP fails when the pasteurised egg can pass the 2nd time without letting the lab know its the same sample.


  • 0




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users