16 replies to this topic

[Zeeshan]

Dear all!

Can somebody provide the authentic reference(s) from which I can find the internationally recommended Fo Value for ready to eat meals. We are producing low acid, hermetically sealed, retort processed food items. Also, whether Fo value depends on product and/or factors? Our retort plant manufacturer recommended a general range of Fo Values as 8~15 for all of our ready to eat products. One of our customer recommended a range 7~10. BTW, our product categories includes ready to eat rice, vegetables, meat, curry, cereals and BBQ range.

Prior thanks for any help.

Regards:
M.Zeeshan

[Charles.C]

Dear Zeeshan,

Not my specific area but I suspect yr question is very difficult to give a general answer for a specific (process/legal requirements unknown) situation.

If you look at the link inside the post referenced below, some ideas of the requirements may be seen -

http://www.ifsqn.com...dpost__p__45025

Rgds / Charles.C

PS I presume this is effectively an equivalent post to yr preceding one ?

[DAVE84]

Hi Zeshaan,



Fo value more than 10 will be more harsh on your product and also not required. you customer is correct Fo value inbetween 8 to 9 will be good enough and will give your better quality of your product. For better dicisonn you will need to conduct heat penitration test and i would suggest you to follow 12 D concept. I believe that your cooling of retort starts at certain Fo value . or do you have time temperature combinations? (called as schedule process)?


Regards

Dave

[Zeeshan]

Dear Dave,
First of all, thanks for your reply. I need some clarification of some points highlighted by you and there's, of course, some need to give answers to your queries.

For better dicisonn you will need to conduct heat penitration test and i would suggest you to follow 12 D concept.

Could you please give me some detail or refer me to the source where I can find the detail of heat penetration test and 12 D concept.

I believe that your cooling of retort starts at certain Fo value . or do you have time temperature combinations? (called as schedule process)?

The cooling of retort starts automatically with set time temperature combinations.

Also, I need to get some information regarding following previously asked queries:

1) Authentic reference(s) from which I can JUSTIFY the recommended Fo Value (8~9) for ready to eat meals.

2) Whether Fo value depends on product and/or other factors? I came to know that low Fo value is enough for vegetable and somewhat higher is recommended for meat products?

3) Is it suitable with respect to quality and food safety of product to set the sterilization process such that higher temperature is given to the product at the start of sterilization process (thermal shock)?

Regards:
M.Zeeshan.

[DAVE84]

Hi Zeeshan,

Basically heat penitration is the process where you study that how your product is getting heated. In heat penitratrion curve you will find heating and cooling lag factors ( Definations you will find in book). This factors will help you to calculate lathality during whole process (using balls formula). Talking about 12D concept. Each organism has its own D value. It is a time required to kill 90% of bacterial at give temp. Canning industry follows 12 D reduction of target organisms. For example assume that your product before retorting have 10^11 cfu/ml and you have 1000 pouches. so if you achieve 12 D reduction you will end up with 0.1 cfu/ml so you can have only 1 pouch in which you have probability of bacterial survival and its probability will be 0.1 only.For example D value for C. Botulinum is 0.2 that 12D means 2.4. It means that you have to achieve atleat F0 value of 2.4 to be safe. But in general industry process goes upto F0 6 to 8 because of safety factors.

For authentic referance for F0 values for different foods you will have to search some canning process book. Each type of food has its different F0 value. There is no standard F0 value for ready to eat product. For example for pea it can be 3 and for paneer it can be 6. There are number of books where you can find F0 value for different products (try to search books on canning process).

F0 value will depend on number of factor but main factor is pH. If you product pH is greater than 4.6 than you will need height F0 value and if its less than 4.6 than you will need lower F0 value (because of acidic nature of product).

I have a small article of calculatin a F0 value that i will provide you tomorrow as its on my laptop.

Heat penitration test is done on new product to see how sooner or later the new product gets heated. For example if you come up with new product which is more thick and has more solids than your standard time temperature for other products will not give same F0 value for this product. Heat penitration study will give you idea about how much time you will require for your new product and at what temperature.

I assume you are using ellab for temperature monitoring.

Regards
Dave

Edited by DAVE84, 25 April 2011 - 05:42 PM.

[Charles.C]

Dear Zeeshan,

Are you saying you are alllowed to commercialise yr products without any preliminary legal approval of yr sterilisation process ?.

Sincerely, I am amazed.

Rgds / Charles.C

[AS NUR]

Agree with Dave.. i am use 12 D Concept to my retort process. and i think dave gave the clear enaough on 12 D concept

[Zeeshan]

Dear Dave,

Thanks for detailed reply. it really gives a great help in clarify many cocepts.

Dear Zeeshan,

Are you saying you are alllowed to commercialise yr products without any preliminary legal approval of yr sterilisation process ?.

Sincerely, I am amazed.

Rgds / Charles.C

No, probably you have guessed wrong. There are actually no requirements (local or of our customers') related to legal approval of sterilization process. The only requirements related to safe and legal end product are "safe Fo value" and "fit for human consumption test from an accredited laboratory". We are working over safe range of Fo values but recently started a research work to adjust this range for better quality of our food product without compromising food safety.

Don't worry. Our food products are safe (legally and actually) as our QA and QC departments' staff is still working safely with good health for 2 years..

Regards:
M.Zeeshan.

[DAVE84]

Dear Chales,

The main idea of retortable product is to attain commercial sterility. It means " product free of bacteria which are able to grow at normal storage condition". Just in case if FDA asks you questions than if you proove that your product is commercially sterile (independent to F0 value) than you will not have any problem.

Best Regards
Dave

[Charles.C]

Dear Dave,

I am not in USA and my previous (canning) experience is 15+ years old but i believe that at that time, one had to USA/FDA register the process sterilisation details in order to legally market the product?. In the case of low-acid products, I can recall using an official publication defining minimum processing conditions for a range of products / can sizes ?

One quite common consequence (at that time) of a lack of knowledge of the kind of data to which Zeeshan is referring was exploding cans before, during or after shipment. (Of course, lack of appropriate sealing procedures is also a major opportunity for disaster). Was (and maybe still is) excellent business for inspection companies though.

I concluded from my interactions in this field that it is remarkably easy to produce shelf-stable products. Especially unstable (and possibly unsafe) ones. Of course, such issues are typical (and valid IMO) reasons for justification of official control measures to exist.

@Zeeshan, It might be interesting if you could post a typical example of the (safe) current process conditions / validation to which you are seeking further guidance on ? I deduce that you are actually seeking individual self-assurance of their reliability ? Unfortunately, as you can probably see, a not-inconsiderable knowledge of theoretical food technology is required in addition to appreciating the (safe) compromises required to make the conclusions operationally practical.

Rgds / Charles.C

[Dr Ajay Shah]

Hi Zeeshan,

You can contact the following Campden BRI and they can assit you with your questions as they have written books on Canning.

Here are the details:

http://www.campden.c...-processing.php

You can also consult the following book which is a good text on the subject of canning

• P.J. Fellows. Food Processing Technology: Principles and Practice, 2nd Edition . Woodhead Pub. 1999

Canned Foods: Introduction to Their Microbiology
(ISBN: 0700014012 ) by A.C. Hersom, E.D. Hulland

Canned Foods by A. C. Hersom and E. D. Hulland

Edited by Dr Ajay Shah, 28 April 2011 - 06:59 AM.

[DAVE84]

Hi Charles,

You might be correct. As my experience with thermal processing is not from USA.

Regards
Dave

[Charles.C]

Dear Ajay Shah,

Yr Campden suggestion is excellent but one crucial snag. Usually (invariably?) costs money.

I suspect Campden probably hv one of the best reservoirs of knowledge on a variety of food related topics in the UK but sadly it is mostly hidden from view for most "ordinarily" funded people. It is fortuitous that other official sources exist of a more freely distributive nature.

Actually I think Zeeshan is not working with canned foods as such (my misleading error ) although i assume the general heat penetrative principles are closely related (or not ??).

Rgds / Charles.C

[Dr Ajay Shah]

Dear Charles. C.

These days everything costs money. Every course one has to attend costs money and thise das where free information was readily available have all gone. We now live in a commercail world!!

Regards

Ajay Shah

[Charles.C]

Dear Ajay Shah,

These days everything costs money. Every course one has to attend costs money and thise das where free information was readily available have all gone.

In specific cases I (obviously) agree. But in general, the internet has surely both created and sustained the opportunity for the exact opposite. For example via forums like this one and the generosity of people like yr goodself.

Rgds / Charles.C

[pablo coronel]

Cook value is calculated in a similar manner than F-values

The variables in this case are diffeent, such as Thiamine destruction, Vitamin C destruction of Chlorophyl, change sin texture, etc
It was introduiced by Mansfeld sometime in the 50s who used a Tref=100C and Zc=33 C

In general a cook value larger than 30 means a noticeable damage to the quality of the food.

A good table with kinetic data can be Found in the new version of Holdsworth's aseptic processing book,

[pablo coronel]

Apologies, I was redirected to this thread from another one discussing Cook values.

Anyway, Campden published a guide regarding the history and use of the Botulinum Cook (F0 value)
It is worth a good read, and yes it is costly to become part of a consortium like that but if you want to make money you have to invest some.

I think a F0 value of 6 to 9 is generally a good average thermal process. The key is to determine the location of your cold spot accurately!!!
Safety is non negotiable and I would not dare risking people's lifes or the reputation of my company/myself.

Cook value is calculated in a similar manner than F-values

The variables in this case are diffeent, such as Thiamine destruction, Vitamin C destruction of Chlorophyl, change sin texture, etc
It was introduiced by Mansfeld sometime in the 50s who used a Tref=100C and Zc=33 C

In general a cook value larger than 30 means a noticeable damage to the quality of the food.

A good table with kinetic data can be Found in the new version of Holdsworth's aseptic processing book,