17 replies to this topic

[Andras_Gergely]

Hi all,

 

I'd need a bit of advise. What would be a microbiological kill step in a Ready-To-Eat root vegetable production process, that eliminates microbiological risk. Heat treatment is not an option, but peeling takes place. Please advise.

[Charles.C]

Hi all,

 

I'd need a bit of advise. What would be a microbiological kill step in a Ready-To-Eat root vegetable production process, that eliminates microbiological risk. Heat treatment is not an option, but peeling takes place. Please advise.

     

Irradiation.

[LesleySR]

Hi Andras

 

Most people in Europe don't like to use irradiation as the mandatory requirement to add the "Radura" symbol on packaging can be a big turnoff for consumers, also there are rules on what products can be treated :-(

 

In raw vegetable products a wash step with Chlorine or PAA is the the most usual way to decontaminate vegetables (eg. bagged salads)

Edited by LesleySR, 14 January 2020 - 12:43 PM.

[gardenfreshqc]

Andras,

 

Are you processing whole peeled root vegetables or are they peeled and diced? We process them both ways where I work. All of our root vegetables are washed in a monitored chlorinated wash system. Additionally in the United States a lot of Root vegetables fall under the RCR or rarely consumed raw guidelines that the FDA puts out. For some larger customers whom we know are cooking these vegetables we have gotten away with just putting a label on our cases stating that these products must be cooked before eating. 

 

 

Regards,

 

Adam

[Andras_Gergely]

Hi Adam,
Thanks for your advise.
The idea would be to peel the root vegetables (e.g. beetroot), mince and blend them with other ingredients. The final product must be Ready-to-Eat, but cannot be heat treated.
Obviously I can't wash the minced materials as they would lose most of their values.
I wonder if peeling (maybe steam peeling) and chlorine washing of whole vegetables would suffice to make the final product ready to eat.
Can you please suggest?
Thank you.
Regards,
Andras

[Andras_Gergely]

Hi Andras

 

Most people in Europe don't like to use irradiation as the mandatory requirement to add the "Radura" symbol on packaging can be a big turnoff for consumers, also there are rules on what products can be treated :-(

 

In raw vegetable products a wash step with Chlorine or PAA is the the most usual way to decontaminate vegetables (eg. bagged salads)

Hi Lesley,

Thank you for the advise.

 

Silly question: Would the peeling (maybe steam peeling) and chlorine/PAA wash suffice to make the material Ready-To-Eat? Just worried about bacteria may be present in the matrix (inner areas) of the roots.

 

Would washing in hydrogen peroxide solution be an option too?

 

Thank you.

Regards,

Andras

[Charles.C]

Hi all,

 

I'd need a bit of advise. What would be a microbiological kill step in a Ready-To-Eat root vegetable production process, that eliminates microbiological risk. Heat treatment is not an option, but peeling takes place. Please advise.

 

I suggest a little study of the Literature -

 

For target organism -

 

heat/pasteurisation  = typically ca. 6D or less

heat/canning (sterilisation) = 12D

chemical treatments = typically ca 2-3 D

 

This illustrates the difficulty in  "elimination" ? A compromise is unavoidable if heat/irradiation are not an option.

[Ryan M.]

Chemical treatments such as with chlorine, peracetic acid, hydrogen peroxide, etc are not considered "lethality treatments" on their own.  Typically, they are part of other process steps to have a lethal treatment.

 

See Charles's post above.

 

You can do a microbiological study of your root vegetables comparing the microbial load before and after a chemical treatment to see if the reduction is sufficient, but you would then have to set, monitor, and prepare to reject raw materials that don't meet the initial microbial load coming in as your chemical treatment can likely only achieve 1 to 3 log reduction.

[Andras_Gergely]

Thanks Ryan,

 

In certain applications raw root vegetables are used to make Ready-To-Eat foods (e.g. coleslaw salad).

 

What would be in these processes the measure against micro contamination?

 

Do I need to have a kill step (e.g. chlorine/PAA or hydrogen peroxide wash) in the process at all?

 

Please advise.

 

Thank you.

Regards,

Andras

[Andras_Gergely]

Thanks Ryan,

 

In certain applications raw root vegetables are used to make Ready-To-Eat foods (e.g. coleslaw salad).

 

What would be in these processes the measure against micro contamination?

 

Do I need to have a kill step (e.g. chlorine/PAA or hydrogen peroxide wash) in the process at all?

 

Please advise.

 

Thank you.

Regards,

Andras

 

I should put the finished goods in jars too, without heat treatment.

[Charles.C]

Thanks Ryan,

 

In certain applications raw root vegetables are used to make Ready-To-Eat foods (e.g. coleslaw salad).

 

What would be in these processes the measure against micro contamination?

 

Do I need to have a kill step (e.g. chlorine/PAA or hydrogen peroxide wash) in the process at all?

 

Please advise.

 

Thank you.

Regards,

Andras

 

Hi Andras,

 

This document details Ireland's  microbiological requirements for ready-to-eat foods placed on the Market -

 

 GN3_Rev3_Accessible.pdf   335.23KB   15 downloads

 

With respect to salads, coleslaws based on mayonnaise the attached extract may be helpful -

 

 mayonnaise, dressings, salads.pdf   967.38KB   16 downloads

 

Note that there are a few previous threads here related to coleslaw, ie -

 

https://www.ifsqn.co...-of-shelf-life/

 

https://www.ifsqn.co...eslaw-dressing/

 

https://www.ifsqn.co...cut-vegetables/

 

https://www.ifsqn.co...-bulk-coleslaw/

[Andras_Gergely]

Hi all,

 

I obtained more data.

 

The materials in question would be horseradish based relishes. These should be canned in jars. Heath treatment would cause the horseradish to lose its strength.

However all products would contain vinegar and salt.

 

Would the pH (and maybe salt content) suffice to control microbiological hazards (survival and growth) and make the product shelf stable?

 

Thank you.

[Charles.C]

Hi all,

 

I obtained more data.

 

The materials in question would be horseradish based relishes. These should be canned in jars. Heath treatment would cause the horseradish to lose its strength.

However all products would contain vinegar and salt.

 

Would the pH (and maybe salt content) suffice to control microbiological hazards (survival and growth) and make the product shelf stable?

 

Thank you.

 

Seems like Yes.

 

 horseradish.PNG   392.23KB   1 downloads

 

 

The details of the processes that are needed to assure safety of acidified vegetables  are  included  in  process  filings, which manufacturers file with the Food and Drug Administration (FDA).  There are two kinds of processes that have been shown to assure a five log reduction in acid resistant pathogens. The acid present in some products may be sufficient to assure a five log reduction in numbers of acid resistant pathogens. For this reason, products with acetic acid as the primary acidulent  and  a  pH  below  3.3  do  not require a heat process, but do require a temperature dependent holding time to assure  safety  (3).  E.  coli  O157:H7  has been found to be the most acid resistant pathogen  of  concern  for  these  products (3). To achieve a five log reduction at  77 o F  (25 o C),  a  holding  time  of  48 hours  is  needed.  However,  at  50 o F(10 o C),  a  holding  time  of  six  days  is required for a five log reduction. Interestingly, L. monocytogenes, a psychrotrophic  organism,  which  can  grow  at  refrigeration  temperatures  at  neutral pH,  does  not  survive  as  well  as  E.  coli O157:H7 under similar cold and acidic conditions (3).

(Breidt,2010)

 

 

Note that above quote concerns safety only. Shelf life may also involve "quality" factors and from reading a few articles on HR sauces this item is clearly not easy to produce in shelf-stable forms.

[Andras_Gergely]

You're star Charles,

 

Silly questions. The material is supposed to be clean label, thus I cannot use Sodium-benzoate and Potassium-sorbate as preservative.

Would the low pH work without these inhibitors?

 

As far as I understand 48hours long exposure to 3.3 pH on room temperature delivers 5 log reduction. Fair enough. How do I (if I'm allowed or able to at all) increase it back to the desired level in the finished product?

 

Sorry for the stupid question.

 

Thank you.

 

Best regards,

Andras

[Charles.C]

You're star Charles,

 

Silly questions. The material is supposed to be clean label, thus I cannot use Sodium-benzoate and Potassium-sorbate as preservative.

Would the low pH work without these inhibitors?

Not sure,  I think they are there for additional spoilage control, see the attached pic below)

 

As far as I understand 48hours long exposure to 3.3 pH on room temperature delivers 5 log reduction. Fair enough. How do I (if I'm allowed or able to at all) increase it back to the desired level in the finished product?

afaik, you don't, the <3.3 is a required final equilibriated value (also see example attached below)

 

Sorry for the stupid question.

Not stupid at all, this is a complicated system mix.

 

Thank you.

 

Best regards,

Andras

 preservatives.PNG   40.78KB   0 downloads

 

I should add this is not my area of expertise and is clearly highly diverse in respect to ingredients/possibilities. And possibly risks also, hence the Regulatory aspects.

 

JFI, I have attached -

 

(1) the reference from which I quoted in previous post.

(2) a worked example to produce a horseradish sauce which, for a pH of 3.5, was not shelf-stable. (maybe pH, maybe lack preservatives ?)

 

 Thermal processing of acidified foods.pdf   154.55KB   10 downloads

 sauces and pickles.pdf   246.19KB   9 downloads

[kfromNE]

For acidified foods between 4.1 to 4.6

 

 

Attached Files

•  4.1_4.6ThermalProcessing.pdf   288.59KB   12 downloads

[Charles.C]

For acidified foods between 4.1 to 4.6

 

Hi kfromNE,

 

The difficulty is that for this matrix  heat treatment is apparently not an option (post 12).

[kfromNE]

Hi kfromNE,

 

The difficulty is that for this matrix  heat treatment is apparently not an option (post 12).

Missed that part. That is the difficult part.