17 replies to this topic

[chrisrushworth]

Morning guys,

 

Customer complaint of "mouldy cheesecakes"

 

Context -

Frozen RTE Cheesecakes

Biscuit base with syrup & marg (heated +72°)

Cheesecake mix

Raspberries & Drizzle on top

 

Defrosted life 3 days.

Discolouration located @ customer warehouse after left OUR control, haulier to frozen storage, haulier to customer depot.

 

Issue-

Visible "discolouration" to biscuit base (green tinge)

 

Tested :

FP :No Yeasts / Moulds detected 

Raw Materials : No yeasts / Moulds detected

 

 

Ideas???

Chemical reaction -

bicab and salt?

Frozen fruits & alcohol in compound?

 

TEMPERATURE failure by haulier or receiving depot?

 

At a bit of a loss, anyone got any ideas?

 

 

[AZuzack]

The finished product that was tested, was that the product with the green discoloration or other product?  How much finished product was impacted?  a single cheesecake?

 

Could have been the air quality on the day of manufacture/packaging.  St. Louis has really high mold spores days.  Or maybe you have an air filter needs to be replaced.  You could do some environmental testing to see what kind of molds you have floating around in your plant.  

[chrisrushworth]

HI

 

FP was tested on DOM and was clear.

Then challenge test of top, centre & bottom of pallet were tested - all negative

 

Then challenge test of x3 cases with visible "mould" tested - all negative....

 

Challenge test of just "mouldy" biscuit has been sent today, but is a +5 day rose Bengal test...

 

I have settle plates from a week before with counts <1... 

I get where your coming from but wouldn't all the cases packed +1000 on x4 SKU's have some sort of "growth"

 

 

 

I was thinking is it maybe mould in cake boards? As out of 176 cases x8 have visible "discolouration"..

 

Im thinking root cause is temperature abuse once left "out" control, either by stores or depot picking layers ....

[AZuzack]

For the environmental, I was thinking more of an outside contamination that hitched a ride on an employee.  Like they tucked their hair under their hairnet and didn't re-wash their hand.  

 

If it came in with biscuit mix, then it would be like a needle in the haystack.  That's the problem with all microbial testing.  A negative doesn't really mean that the organism isn't present, just that it wasn't detected in the sample.  

 

If it was on packaging, then it's more likely that an employee touched it with a contaminated hand or glove.  But cardboard if it got damp could be a source.  I don't necessarily mean wet, we have all kinds of humidity issues where I am at.  Add a random mold spore... you could sponge/swab the cardboard but that's just a different haystack at this point.  

 

I think you have done your due diligence at this point.  If it wasn't wide spread throughout an entire batch, it is really hard to pin point a true root cause.  I agree that any visible mold growth is likely the result of temperature abuse, but you probably are not going to identify the source of the mold.  

 

Good news is that there's a handful of other users that responds to the same threads I respond to, so there may be more opinions coming.  @Scampi, @GMO, @SQFconsultant, @Setanta  I don't think the tagging works on the forums but I also had never tried.  

[SQFconsultant]

I'd be looking at the Margarine.

[Tony-C]

Hi chrisrushworth,

 

Sounds a bit weird, this is a frozen product that hasn’t been (or shouldn’t have anyway!) defrosted, right?

 

Last year I found a load of moulds in frozen flaky pastry which was quite annoying as it wasn’t cheap. I’m pretty sure that was temperature abuse and the sheets were packed in layers separated by wax paper.

 

A few questions:

Is this random or from a start or end of a production run?

How old is the product?

Are the cake boards made from cardboard/waxed cardboard? Cardboard is notorious for Y&M

Have you tried abusing some of the product to see if you get the same result?

Would posting a photo help?

 

Be interesting to see what you biscuit analysis comes up with.

 

Kind regards,

 

Tony

[chrisrushworth]

Hi chrisrushworth,

 

Sounds a bit weird, this is a frozen product that hasn’t been (or shouldn’t have anyway!) defrosted, right?

 

Last year I found a load of moulds in frozen flaky pastry which was quite annoying as it wasn’t cheap. I’m pretty sure that was temperature abuse and the sheets were packed in layers separated by wax paper.

 

A few questions:

Is this random or from a start or end of a production run?

How old is the product?

Are the cake boards made from cardboard/waxed cardboard? Cardboard is notorious for Y&M

Have you tried abusing some of the product to see if you get the same result?

Would posting a photo help?

 

Be interesting to see what you biscuit analysis comes up with.

 

Kind regards,

 

Tony

 

 

Morning,

 

Thanks for your time.

 

Yep frozen should only be defrosted +3h prior to service in a 0-8° chiller/fridge....

Product was made in FEB, customer alerted product in APR, they have x6 pallets and only seems to be one pallet effected - which makes me think there is temp abuse at there end.

I did some abuse trials here, left out ambient for +13 days until visible mould growth...

 

Regards to MARG - if it was the marg, this would affect alot more SKU & is heated +72° to melt... thus mould should be denatured?

 

I'm thinking it the card cake boards, there FG and coated..

Speaking with my lab apparently from a sponge p/a swab they can enumerate Y&M tests.. what's people thoughts on this?

 

Am i just seeking that needle in the haystack, as there have been no further complaints or re-occurrence since??

Just close out as root cause proabable temperature abuse.?? How far do i go?

[AZuzack]

I know I called the cardboard a haystack, but it shouldn't cost all that much to test it.  Sponge swabs are fairly easy to do and send off to a lab.  Even if the sponges come back negative, it doesn't mean that it wasn't the cardboard.

 

Bottom line is that without some amount of temperature abuse, mold growth is highly unlikely.  Mold spores are relatively common in the air, on clothes, in warehouses, etc.  Best you can do is attempt to find a source (which you have done).  If the source isn't a "harborage" site, like a drain that isn't being cleaned or an air filter that needed to be replaced, then you're mostly left with addressing the mobility of mold spores in your employee GMP training.  If the cardboard does come back positive for yeast and mold, then you can try to work with the supplier on manufacturing and storage conditions.  

 

You could fishbone diagram this and then show your investigation for each possible cause and that should cover you.  You've clearly identified multiple potential sources and attempted to prove/disprove them.  

 

For the customer, I think you go the temperature abuse route. Internally, you test the card board.  

 

As for temperature abuse in the delivery system, do you have records of the refrigerated truck temperature set points or product temperatures when it was received?  

[chrisrushworth]

I know I called the cardboard a haystack, but it shouldn't cost all that much to test it.  Sponge swabs are fairly easy to do and send off to a lab.  Even if the sponges come back negative, it doesn't mean that it wasn't the cardboard.

 

Bottom line is that without some amount of temperature abuse, mold growth is highly unlikely.  Mold spores are relatively common in the air, on clothes, in warehouses, etc.  Best you can do is attempt to find a source (which you have done).  If the source isn't a "harborage" site, like a drain that isn't being cleaned or an air filter that needed to be replaced, then you're mostly left with addressing the mobility of mold spores in your employee GMP training.  If the cardboard does come back positive for yeast and mold, then you can try to work with the supplier on manufacturing and storage conditions.  

 

You could fishbone diagram this and then show your investigation for each possible cause and that should cover you.  You've clearly identified multiple potential sources and attempted to prove/disprove them.  

 

For the customer, I think you go the temperature abuse route. Internally, you test the card board.  

 

As for temperature abuse in the delivery system, do you have records of the refrigerated truck temperature set points or product temperatures when it was received?  

 

 

Hi

I have temperature logs from haulier leaving site, to their storage depot, lorry temps, delivery temps.

Customer has failed to provide any temperature logs their end...

They have also used this pallet out sync as have had x4 other deliveries of x6 pallets... but this pallet from the first delivery is where the issue is.

I think they have **ed up and are trying to get us to PAY for the stock that they cant sell...

 

 

Thanks for all advice..

[Tony-C]

Hi

I have temperature logs from haulier leaving site, to their storage depot, lorry temps, delivery temps.

Customer has failed to provide any temperature logs their end...

They have also used this pallet out sync as have had x4 other deliveries of x6 pallets... but this pallet from the first delivery is where the issue is.

I think they have **ed up and are trying to get us to PAY for the stock that they cant sell...

 

 

Thanks for all advice..

 

Hi ChrisRushworth,

 

If the problem products are all from a single pallet of 'old product' then I would agree with you, very suspicious. Still worth documenting your findings/investigation.

 

To clarify, so far your micro tests haven't turned up any Y&M counts? It is just visible 'moulds'? Let's see what the biscuit analysis turns up and I think it is worth sponge swabbing the card cake boards. If it is the card then this may be an area where improvements can be made although clearly the facts point to significant abuse being the cause.

 

Kind regards,

 

Tony

[chrisrushworth]

Hi ChrisRushworth,

 

If the problem products are all from a single pallet of 'old product' then I would agree with you, very suspicious. Still worth documenting your findings/investigation.

 

To clarify, so far your micro tests haven't turned up any Y&M counts? It is just visible 'moulds'? Let's see what the biscuit analysis turns up and I think it is worth sponge swabbing the card cake boards. If it is the card then this may be an area where improvements can be made although clearly the facts point to significant abuse being the cause.

 

Kind regards,

 

Tony

Morning Tony,

 

Yep, thats what im thinking/doing

 

Its more about my own interest now trying to determine root cause to prevent re-occurrence, but im confident of my guys downstairs and the controls / PRP's we have in place...

 

Will update once results in :P

[chrisrushworth]

Sooo.

 

No Y&M found on any additonal FP tests.

No Y&M found on any layer boards tested.

No Y&M found in "green" biscuit.

 

 

Thus, is a quality issue.

 

So now I'm thinking, is this to do with the natural colours in the product, then using the colour wheel they look "green/brown/blue" on the biscuit base?

 

Is it to do with the alcohol in the mix, drawing through the "red" colours (amino b/red iron oxide) and thus discolouring the biscuit base?

 

No further complaints, and i have not managed to recreate the same issue in frozen conditions, as i said before an abuse trial at ambient (10-20°) took +14 days for "visible" growth

 

...

[GMO]

Hmm.  Now this is a noodle scratcher.  Sorry I didn't get the "tag" (though that's a good idea Simon if we could!)

 

So just to go back, green found in the base of the cheesecake.  Only in the base, not in the higher water activity top?  That in itself seems odd.

 

But also it's query mould as when tested no Y&M were found.

 

Your most recent reply I think is a possibility.  A colour leaching issue rather than mould.

 

What is the card you're using?  Is there any recycled content?  Could you do some rough and ready experiments?

 

Things like - coloured items in the mix, do they bleed into the base and cause a "greenish" colouring?

 

Is there anything in the card which could leach out?

 

I'm trying to imagine your product.  As I'm thinking of it I'm thinking if you have a base made out of biscuits and margarine (which unless it's low fat will be pretty much bullet proof I'd think apart from oxidation?)  That goes onto board.  That board could have something(?) leaching out of it if it's not coated or that coating has failed?  Then you have ingredients including colour into the cheesecake layer which, especially if it's been temperature abused, would then cause moisture migration in and out of the biscuit layer.  You know like when you leave a cheesecake in a fridge too long and it goes soft at the base.

 

What if they did have temperature abuse but it wasn't long enough to cause microbial growth but was long enough for some physical and chemical properties to change?  Maybe it defrosted but was still held cold?

 

A question, how soft / firm was the biscuit base on the rejected product vs retained samples?  I think that could be an indicator of previous abuse and refreezing irrespective of whether it was a micro or physical / chemical issue.

[chrisrushworth]

Hmm.  Now this is a noodle scratcher.  Sorry I didn't get the "tag" (though that's a good idea Simon if we could!)

 

So just to go back, green found in the base of the cheesecake.  Only in the base, not in the higher water activity top?  That in itself seems odd.

Yep, only "discolouration" on base only.

 

But also it's query mould as when tested no Y&M were found.

 

Your most recent reply I think is a possibility.  A colour leaching issue rather than mould.

 

 

What is the card you're using?  Is there any recycled content?  Could you do some rough and ready experiments?

We have checked the layer cards, no Y&M counts found, and would be across multiple SKUs if was layer card.

 

Things like - coloured items in the mix, do they bleed into the base and cause a "greenish" colouring?

This is what our thinking is going along, that the "red" fruit are reacting/leaking causing a reaction between marg (baking powder)

 

Is there anything in the card which could leach out?

Cards are white and un cloured and PE coated

 

I'm trying to imagine your product.  As I'm thinking of it I'm thinking if you have a base made out of biscuits and margarine (which unless it's low fat will be pretty much bullet proof I'd think apart from oxidation?)  That goes onto board.  That board could have something(?) leaching out of it if it's not coated or that coating has failed?  Then you have ingredients including colour into the cheesecake layer which, especially if it's been temperature abused, would then cause moisture migration in and out of the biscuit layer.  You know like when you leave a cheesecake in a fridge too long and it goes soft at the base.

 

What if they did have temperature abuse but it wasn't long enough to cause microbial growth but was long enough for some physical and chemical properties to change?  Maybe it defrosted but was still held cold?

 

A question, how soft / firm was the biscuit base on the rejected product vs retained samples?  I think that could be an indicator of previous abuse and refreezing irrespective of whether it was a micro or physical / chemical issue.

 

Bases do seem to be softer than usual, there was a "residue" on the card

[GMO]

I agree with you that it's probably not microbiological but one thing I've done in the past with card is actually send the card off as a product sample (not just swabbing the card) as it's pretty difficult to pick up on a swab from it.  Might be worth ruling out.  The lab can then stomach the card with the nutrient broth.

 

Oooh...  Ok, baking powder.  Where is that from?  Is it in the biscuits?  Baking powder should have enough acid in it to cause the reaction for the carbon dioxide release and rising (not always used in biscuits though?)  BUT if there was some remaining base in there and not enough acid to activate it (sodium hydrogen carbonate), it could be acting as a natural pH indicator with your red fruits.  

 

Here is a pH colour graph.  Some natural indicators are pretty dramatic in the changes.

 

 

So now you've said about the soft bases, this is where I'm thinking... Go with me...

 

The site put the pallet somewhere they shouldn't have.  It started to defrost and even if it was kept in chill and not defrosted completely, it started moisture movements within the product.  It was still cold enough though that there was no mould growth.  This resulted in softer bases but also meant the red fruits in your cheesecake in some cases came across some unreacted sodium hydrogen carbonate in the biscuits which then resulted in a pH change.  The pH change will mostly be around the base of the cheesecake because you packed them base down to prevent damage and the juice from any fruits in the top is more likely to migrate than the bicarb.  Is that a crazy theory?

[kingstudruler1]

could it be some type of chemical reaction similar to:   (sorry didnt read the whole thread)

 

 

Alternatively, the green color can be a result of a chemical reaction between ingredients, like baking soda and chlorophyll or chlorogenic acid, especially when using sunflower seeds or flour. 

[GMO]

Just thinking this morning about a test to try this out, and, if that works, how you could respond.

 

Could you get some of the juice / fruit that you use and some sodium hydrogen carbonate (aka bicarb / baking soda) and see if you get a colour change?  You might have to dilute it to be able to see it fully.  Is it also worth trying that with your biscuit crumb?

 

If that then works, you could potentially go back to your customer and say something along the lines of:

 

(Allow them a way to save face in this.  I sometimes put it through Copilot and ask it to put it in a friendlier tone!)

 

• We have a working theory as to the cause of this issue.
• We have temperature records up to delivery to confirm that the product was held below xx degrees.
• We have undertaken testing of xx samples in the product and packaging and found no evidence of yeast or mould presence.
• The visuals (add photo) do not look like mould and the location of the discolouration is unusual.  Mould, if present is more likely to occur in the topping which has a higher water activity.
• Therefore, we have excluded a microbiological cause for this discolouration.
• We noted the bases had softened and the discolouration was in the vicinity of the biscuit base.
• The bases remain crisp up to point of consumption when stored frozen and defrosted following pack instructions.
• Our working theory is at some point in storage after xx date (the date you delivered), for example, due to an undetected breakdown, the cheese cakes started to defrost enough to cause softening but not enough to cause microbiological growth.  Juice from the xx ingredient, over time, leeched into the base causing softening.  This juice, over time, appears to have then reacted with the baking powder within the biscuits causing the discolouration with the juice acting as a natural pH indicator.  
• We have replicated this colour change using xxx experiment.
• This colour change does not occur if the cheesecakes are stored frozen and defrosted using the package instructions.
• While this discolouration is not harmful, it is indicative that temperatures have not been maintained in the product for the full storage. 
• We can confirm and provide logs of our temperatures up to point of delivery.
• We have not been able to identify a cause for this issue within manufacturer control.

[chrisrushworth]

 

Just thinking this morning about a test to try this out, and, if that works, how you could respond.

 

Could you get some of the juice / fruit that you use and some sodium hydrogen carbonate (aka bicarb / baking soda) and see if you get a colour change?  You might have to dilute it to be able to see it fully.  Is it also worth trying that with your biscuit crumb?

 

If that then works, you could potentially go back to your customer and say something along the lines of:

 

(Allow them a way to save face in this.  I sometimes put it through Copilot and ask it to put it in a friendlier tone!)

 

• We have a working theory as to the cause of this issue.
• We have temperature records up to delivery to confirm that the product was held below xx degrees.
• We have undertaken testing of xx samples in the product and packaging and found no evidence of yeast or mould presence.
• The visuals (add photo) do not look like mould and the location of the discolouration is unusual.  Mould, if present is more likely to occur in the topping which has a higher water activity.
• Therefore, we have excluded a microbiological cause for this discolouration.
• We noted the bases had softened and the discolouration was in the vicinity of the biscuit base.
• The bases remain crisp up to point of consumption when stored frozen and defrosted following pack instructions.
• Our working theory is at some point in storage after xx date (the date you delivered), for example, due to an undetected breakdown, the cheese cakes started to defrost enough to cause softening but not enough to cause microbiological growth.  Juice from the xx ingredient, over time, leeched into the base causing softening.  This juice, over time, appears to have then reacted with the baking powder within the biscuits causing the discolouration with the juice acting as a natural pH indicator.  
• We have replicated this colour change using xxx experiment.
• This colour change does not occur if the cheesecakes are stored frozen and defrosted using the package instructions.
• While this discolouration is not harmful, it is indicative that temperatures have not been maintained in the product for the full storage. 
• We can confirm and provide logs of our temperatures up to point of delivery.
• We have not been able to identify a cause for this issue within manufacturer control.

 

Morning,

Thanks for your time and assistance!!!

 

We will trial the bicarp and fruits idea and let you know!!!!