26 replies to this topic

[Sarah_E_W]

I've inherited a CCP. MAP - the levels of residual oxygen varies for pack size. Logically the size of the pack shouldn't make a difference whether it's 60g or 600g as the specification of the gas is the same or am I missing something? Also, would there be a reason why two processes would have a different gas mix. Pillow Pack - 100% Carbon Dioxide Shallow Pack - 70% Nitrogen / 30 % Carbon Dioxide. Which one would aid a longer shelf life?

[Scampi]

https://www.modified...Guide-2018.ashx

 

It isn't just dependent on the gas mixture, you need to also consider A) what type of product and B) composition of the packaging

 

The above should help get you started

[Charles.C]

I've inherited a CCP. MAP - the levels of residual oxygen varies for pack size. Logically the size of the pack shouldn't make a difference whether it's 60g or 600g as the specification of the gas is the same or am I missing something? Also, would there be a reason why two processes would have a different gas mix. Pillow Pack - 100% Carbon Dioxide Shallow Pack - 70% Nitrogen / 30 % Carbon Dioxide. Which one would aid a longer shelf life?

 

Hi Sarah,

 

 

As per Post 2, more context/data might assist further comment, eg product ?, declared shelf-lives, etc ?.

 

PS - What on Earth is a Pillow Pack ?

[Slab]

 

PS - What on Earth is a Pillow Pack ?

 

Gas flush, heat sealed, non-vacuum i.e potato chips

[Sarah_E_W]

Hi Sarah,

 

 

As per Post 2, more context/data might assist further comment, eg product ?, declared shelf-lives, etc ?.

 

PS - What on Earth is a Pillow Pack ?

 

 

Hi Charles, 

 

it is cheese, pillow pack is gas flushed heat sealed. 

 

currently if i have 60g-200g the CO2 CCP is <0.6%, If it is 4kg the CO2 CCP is <5% 

 

Pillow pack is 50 days and the other slices 70 days 

[Sarah_E_W]

https://www.modified...Guide-2018.ashx

 

It isn't just dependent on the gas mixture, you need to also consider A) what type of product and B) composition of the packaging

 

The above should help get you started

 

Thank you 

[Charles.C]

I've inherited a CCP. MAP - the levels of residual oxygen varies for pack size. Logically the size of the pack shouldn't make a difference whether it's 60g or 600g as the specification of the gas is the same or am I missing something? Also, would there be a reason why two processes would have a different gas mix. Pillow Pack - 100% Carbon Dioxide Shallow Pack - 70% Nitrogen / 30 % Carbon Dioxide. Which one would aid a longer shelf life?

 

Hi Sarah,

 

I deduce the first 2 sentences of above were unrelated to the last two.

 

Re-first two sentences. TBH I don't see the relevance of CO₂ < 0.6%. What is the rest ? Vac. Pack ?

[Sarah_E_W]

Hi Sarah,

 

I deduce the first 2 sentences of above were unrelated to the last two.

 

Re-first two sentences. TBH I don't see the relevance of CO₂ < 0.6%. What is the rest ? Vac. Pack ?

 

I don't follow? 

Grated cheese is gas flushed with 100% CO2, the residual oxygen varies for the pack size i.e. 100g pack to 4kg  - is this correct? Should there be a variance because of the pack size? I don't think there should be. 

 

Slices cheese is gas flushed with a 70 CO2 and 30 Nitrogen mix, why would the slices use a different gas? Should they not be the same?

Hopefully i've been a bit clearer

[Charles.C]

Hi Sarah,

 

I got lost because -

 

How is it possible for CO2 < 0.6% (or 5%) if flushing with 100% or 70% ?

[Sarah_E_W]

Hi Sarah,

 

I got lost because -

 

How is it possible for CO2 < 0.6% (or 5%) if flushing with 100% or 70% ?

sorry this would be residual oxygen <0.6 

[Charles.C]

I don't follow? 

(A) Grated cheese is gas flushed with 100% CO2, the residual oxygen varies for the pack size i.e. 100g pack to 4kg  - is this correct? Should there be a variance because of the pack size? I don't think there should be. 

 

(B) Slices cheese is gas flushed with a 70 CO2 and 30 Nitrogen mix, why would the slices use a different gas? Should they not be the same?

Hopefully i've been a bit clearer

 

Hi Sarah,

 

Thks yr clarification. I get it now.

 

There are some earlier links on this topic which are partially informative -

 

https://www.ifsqn.co...ion/#entry34065

https://www.ifsqn.co...ap/#entry160483

https://www.ifsqn.co...ccp/#entry51337

 

MAP not my area of expertise but, inter alia, MAP options apparently can also relate to the type of cheese, eg hard/soft.. Are the sliced and grated varieties referred produced from the same type of cheese (also see PPS below) ?

 

Regarding (A) and oxygen levels,  I'm inclined to agree with you. Any chance it was a typo for 0.5% ? ("5%"  might also be related to a limitation in the specific type of packaging equipment involved).

 

Regarding (B) I have looked at  a few sources of suggested cheese/MAP options in Literature but the results are confusing in that (a) they (partially) differ from your setup and (b) they also (partially) differ between each other !

 

The typical reason for using Nitrogen is this  -
 

The main gas that is used in modified atmosphere packaging (MAP) to prolong the freshness of hard cheese is carbon dioxide. Hard cheese can be packaged in an atmosphere of total carbon dioxide, while for soft cheeses the proportion is typically between 20 and 40 per cent, with the remainder being usually nitrogen. The main reason for this approach with softer cheeses is that over time the carbon dioxide can dissolve in the water that is within the cheese, and this reduces the volume of gas in the package, eventually causing the packaging to collapse. The presence of the nitrogen prevents the packaging from collapsing.

https://www.modified...ing-cheese.aspx

 

 

It appears that the originator of your own version believed the risk of collapse to be higher for sliced cheese than grated. If related to surface area I would have thought the opposite to be the case. The latter hypothesis is semi-supported by this extract from a 2nd source -

 

Value-added cheeses, such as grated or sliced cheddar, are also packaged in modified atmospheres. Grated cheese is normally packed in an atmosphere of 70% nitrogen and 30% CO₂. By limiting CO₂ to 30%, manufacturers can avoid package collapse.

https://www.linde-ga...airy/index.html

 

 

However a 3rd source gave this detailed table which differs from both yours and (partially) the 2nd source above.  However 3rd source  does appear to support (reason unknown) the possibility of the choice of gas varying with pack size (but not with respect to O₂).-

 

 cheese and dairy.PNG   68.97KB   0 downloads

 Gas MAP Applications.pdf   1.82MB   18 downloads

 

Quite a puzzle. Maybe other factors such as hard/soft, pillow/shallow aspects are also in play.

 

PS - to answer yr original OP query, the CO₂ level seems to be the primary shelf life extending component for gas flush but whether linear or "X" no idea.

 

PPS - a 4th source gave -

Recommended gas mixtures  
Hard cheeses except mould-ripened cheeses: 100% CO₂

Grated and soft cheeses except mould-ripened cheeses:
0–30% CO₂ , 70%–100 % N₂

Other dairy products: 100% N₂

 Guide to MAP Gas Mixtures.pdf   12.35MB   8 downloads

 

(this is the only observed format so far which [maybe] matches that in the OP )

[karamjit7828]

Hello Charles,

 

Are you able to assist me on the MAP for fresh spinach sealed in LDPE bags? Which gases can be used and what will be the concentration?

[G M]

Hello Charles,

 

Are you able to assist me on the MAP for fresh spinach sealed in LDPE bags? Which gases can be used and what will be the concentration?

 

There are a lot of variables and considerations to balance.  Nitrogen and carbon dioxide are used frequently for economic convenience and to suppress micros.

[karamjit7828]

Will you be able to share the details or documents that will be helpful for me?

 

Do you know any supplier?

[GMO]

I have experience with MAP in cheese. 70/30 and 100% CO2 are both common gas mixes. The purpose of the CO2 is it gets absorbed into the cheese to a level and has an antimicrobial effect. In my experience both work but I suspect you have more CO2 in the grated to maximise the amount for the higher surface area.

The downside to 100% CO2 can be if all the gas is absorbed then it can pull in the packaging like a vacuum which isn’t always desired but if you’re putting enough in that’s possibly not an issue.

So to my mind that’s the reason for the difference. Higher mould risk on grated due to the higher surface area meaning you’re putting in more CO2 to maximise the antimicrobial impact.

The limit on oxygen seems ok. I’ve seen levels ranging from 0.5-1%. From experience 1% is possibly too high. 0.6% might be based on the machinery you have. If you can reliably get it below 0.5% I would.

But probably the most important check is on leaks. As you’re using CO2 there are some great bits of kit to detect leaks based on IR sensors. I think from memory they’re called Dansemsor Leakpointers? Basically they pull a vacuum on test pack(s) and test for CO2 presence in the headspace. Much better than those bubble tanks as they’re more sensitive and if you have several sealing jaws you can test more than one pack at a time.

[GMO]

Dansensor. Fat fingers!

[G M]

...
But probably the most important check is on leaks. As you’re using CO2 there are some great bits of kit to detect leaks based on IR sensors. I think from memory they’re called Dansemsor Leakpointers? Basically they pull a vacuum on test pack(s) and test for CO2 presence in the headspace. Much better than those bubble tanks as they’re more sensitive and if you have several sealing jaws you can test more than one pack at a time.

 

The automated leak detectors are far less sensitive than a bubble emission/submersion test.  I've even been to the lab at Dansensor/Mocon to test the exact levels of capability with known leakers with their engineers.  The main advantage of the automated systems is that they can test every package, and if they do catch a problem, that's a signal for you to go find the rest of them that it missed by doing a more involved and far more sensitive bubble test.

[GMO]

The automated leak detectors are far less sensitive than a bubble emission/submersion test.  I've even been to the lab at Dansensor/Mocon to test the exact levels of capability with known leakers with their engineers.  The main advantage of the automated systems is that they can test every package, and if they do catch a problem, that's a signal for you to go find the rest of them that it missed by doing a more involved and far more sensitive bubble test.

 

I didn't mean the inline machines.  I meant the ones used for sampling checks.  I'd be interested to know what you'd used if these are the ones you're referring to in them being less sensitive but having used them in three manufacturing sites this wasn't our experience?  

These are the kind of machines I'm referring to, albeit the designs have changed slightly.

Dansensor LeakPointer 3 and LeakPointer 3+ - Tendring Pacific

 

Post installation, we had mould complaints plummet and persistent issues found on sealing jaws which required engineering work to repair and some significant replacements.  

I think you may have been referring to in line systems though which is not what I was meaning?

[karamjit7828]

What type of test can be used to  detect that there is no bacteria on the product when product is triple washed?Is there any article that i can read to study about the concentration of gases (Nitrogen, CO2, O2)that can be used in produce packaging? Will those gases have harmful effect on the product that will further cause harm to consumer?

[karamjit7828]

There are a lot of variables and considerations to balance.  Nitrogen and carbon dioxide are used frequently for economic convenience and to suppress micros.

What type of test can be used to  detect that there is no bacteria on the product when product is triple washed?Is there any article that i can read to study about the concentration of gases (Nitrogen, CO2, O2)that can be used in produce packaging?Do you know any supplier?  Will those gases have harmful effect on the product that will further cause harm to consumer?

 

[G M]

I didn't mean the inline machines.  I meant the ones used for sampling checks.  I'd be interested to know what you'd used if these are the ones you're referring to in them being less sensitive but having used them in three manufacturing sites this wasn't our experience?  

These are the kind of machines I'm referring to, albeit the designs have changed slightly.

Dansensor LeakPointer 3 and LeakPointer 3+ - Tendring Pacific

 

Post installation, we had mould complaints plummet and persistent issues found on sealing jaws which required engineering work to repair and some significant replacements.  

I think you may have been referring to in line systems though which is not what I was meaning?

 

 

"Fast & highly accurate. Reliable and repeatedly capable of detecting very small leaks, down to 50 microns (µm)"

 

One of the models we were trialing was a set of Leakpointer cabinets.  The problem is with this^ kind of statement (which they didn't make at the time).  A 500um leak is enormous, and a 50um is still quite large.  By their own marketing material a 50um leak will return a package to 10% oxygen in just 3 days, and that sounds about right from what I've seen (visible spoilage in 3-5 weeks with 20-50um leaks).

 

Most of our economically important leaks are less than 50um.  A novice inspector can detect a 50um leak quite easily by bubble emission, but the machines only managed ~30% detection, and below that the machines nearly always failed.  Exchanging a couple microliters of gas per second under stress wasn't enough to trigger the sensor against background noise, but its still large enough to result in spoilage and consumer complaints.  With the maximum sensitivity they were capable of also being destructive to the package the cabinets weren't saving time or allowing us to recover the good packages.

 

Those being ineffective for the purpose led us to building some custom in-line units in house that would indicate when to increase the sampling rate for a more sensitive test.  Even if it only catches one leak out of a hundred, it will tell us there's a problem in the first few minutes.  From what I've seen/heard there are a couple companies offering something similar now commercially.

 

We still use a bunch of their headspace analyzers though.

[G M]

What type of test can be used to  detect that there is no bacteria on the product when product is triple washed?Is there any article that i can read to study about the concentration of gases (Nitrogen, CO2, O2)that can be used in produce packaging?Do you know any supplier?  Will those gases have harmful effect on the product that will further cause harm to consumer?

 

Air is mostly nitrogen already, it's largely inert so nitrogen gas flush is very unlikely to have any adverse effects.  It's usually also the least expensive.

 

CO2 has the advantage of suppressing some pathogenic and spoilage microorganisms, but has the potential to acidify high moisture items at higher concentrations (CO2+H20 makes carbonic acid), and it usually costs more. Effects of high CO2 MAP are unlikely to be harmful, but flavor and color quality can be unfavorable at high levels. CO2 has an added advantage of allowing leak detection because it is naturally present in the atmosphere at low concentrations, and a leaky package under stress will express detectably higher amounts.  

 

Helium has very good leak detection capability as well, because it is naturally present in the atmosphere at very low levels.  Unfortunately it's also comparably very expensive, and doesn't have the anti-microbial effects of CO2.  Helium is unreactive, and the least likely to have adverse effects.

 

Oxygen is what you want to eliminate or reduce by flushing your package with something else, as it promotes spoilage and quality reduction in a variety of ways.

[GMO]

"Fast & highly accurate. Reliable and repeatedly capable of detecting very small leaks, down to 50 microns (µm)"

 

One of the models we were trialing was a set of Leakpointer cabinets.  The problem is with this^ kind of statement (which they didn't make at the time).  A 500um leak is enormous, and a 50um is still quite large.  By their own marketing material a 50um leak will return a package to 10% oxygen in just 3 days, and that sounds about right from what I've seen (visible spoilage in 3-5 weeks with 20-50um leaks).

 

Most of our economically important leaks are less than 50um.  A novice inspector can detect a 50um leak quite easily by bubble emission, but the machines only managed ~30% detection, and below that the machines nearly always failed.  Exchanging a couple microliters of gas per second under stress wasn't enough to trigger the sensor against background noise, but its still large enough to result in spoilage and consumer complaints.  With the maximum sensitivity they were capable of also being destructive to the package the cabinets weren't saving time or allowing us to recover the good packages.

 

Those being ineffective for the purpose led us to building some custom in-line units in house that would indicate when to increase the sampling rate for a more sensitive test.  Even if it only catches one leak out of a hundred, it will tell us there's a problem in the first few minutes.  From what I've seen/heard there are a couple companies offering something similar now commercially.

 

We still use a bunch of their headspace analyzers though.

 

Maybe my knowledge is old but it's the technology used in every cheese factory (or being implemented) in the UK c. 5-8 years ago and it had massive positive impacts on complaints.

What bubble tanks do you use?  I'm in a different industry now and they use bubble tanks and my opinion is still the same.  Pile of crap to be honest.  

I genuinely have not experienced a good bubble tank yet.  Perhaps it's because it is so reliant on the individual using?

 

Either way thanks for the info but I'm inclined to still go with personal experience that genuinely those leakpointers have been great.  And to be honest, maybe it's about what kind of defect you're looking for?  A 50 micron hole is fine if you're looking for poor heat sealing for example.  We found that we could not detect small leaks on seals with the bubble tanks even with a trained operator trained by the manufacturer and 50 micron was enough to see you had an issue on a seal or not and perhaps you were looking for a different defect?  Still as I say, maybe my knowledge is old.  Sometimes it's easy to forget how much time has passed.

[GMO]

Air is mostly nitrogen already, it's largely inert so nitrogen gas flush is very unlikely to have any adverse effects.  It's usually also the least expensive.

 

CO2 has the advantage of suppressing some pathogenic and spoilage microorganisms, but has the potential to acidify high moisture items at higher concentrations (CO2+H20 makes carbonic acid), and it usually costs more. Effects of high CO2 MAP are unlikely to be harmful, but flavor and color quality can be unfavorable at high levels. CO2 has an added advantage of allowing leak detection because it is naturally present in the atmosphere at low concentrations, and a leaky package under stress will express detectably higher amounts.  

 

Helium has very good leak detection capability as well, because it is naturally present in the atmosphere at very low levels.  Unfortunately it's also comparably very expensive, and doesn't have the anti-microbial effects of CO2.  Helium is unreactive, and the least likely to have adverse effects.

 

Oxygen is what you want to eliminate or reduce by flushing your package with something else, as it promotes spoilage and quality reduction in a variety of ways.

 

What kind of sensor are you using to detect Helium?  

[G M]

What kind of sensor are you using to detect Helium?  

 

The same general category as CO2, spectral interference (light absorption).  The amount needed in the headspace is very low, but its still cost prohibitive for most products.

 

Part of the limit for detecting smaller leaks is the level of stress the packaging can withstand before catastrophic failure induced by the test.  We're performing bubble emission inspections around -900mbar, generating a 300mbar differential on some robust packaging material -- a lot of items on the shelf in a grocery will fail under half that pressure.