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CHEESE TYPE BOARDS (for Cheese Lovers and Cheese Makers) => ADJUNCT - Blue Mold (Penicillium roqueforti) Ripened => Topic started by: michoutim on December 21, 2009, 06:48:32 AM

Title: Blue cheese and copper rods ?
Post by: michoutim on December 21, 2009, 06:48:32 AM

Hi Friends!

Today, at the cheese shop, the owner told me that for the "blue" to spread well inside the cheese, cheesemakers insert  pure copper rods inside the cheese. Copper supposingly helps the blue to spread around.

What do you know about this, please? :P

In the meantime, I wish you a MERRY CHRISTMAS!  :)

Cheers!
Michoutim.

Title: Re: Blue cheese and copper rods ?
Post by: FRANCOIS on December 21, 2009, 07:35:20 AM

I have seen mutiple commercial plants for blue cheese and I can tell you this is not industry norm.  I doubt it would even be legal in most places since food contact utensiles have to be stainless in many countries.  The piercers we use are stainless.

Title: Re: Blue cheese and copper rods ?
Post by: linuxboy on December 21, 2009, 06:39:31 PM

There is no scientific basic in claiming that copper helps with blue growth. Temperature, oxygen, and available food are the three biggest factors in blue mold growth, along with pH and humidity. As Francois said, the mechanical piercers all use stainless rods.

Title: Re: Blue cheese and copper rods ?
Post by: michoutim on December 21, 2009, 10:27:45 PM

Many thanks to François and Linuxboy!  :)

Title: Re: Blue cheese and copper rods ?
Post by: justsocat on December 24, 2009, 12:38:17 PM

Quote from: linuxboy on December 21, 2009, 06:39:31 PM

There is no scientific basic in claiming that copper helps with blue growth. Temperature, oxygen, and available food are the three biggest factors in blue mold growth, along with pH and humidity. As Francois said, the mechanical piercers all use stainless rods.

And what is an influence of pH on blue mold growth? I probably miss something?

Title: Re: Blue cheese and copper rods ?
Post by: driekus on December 31, 2009, 12:49:57 AM

Sorry for chipping in so lately but I always thought copper was toxic to most bacteria and mould.
http://www.caes.uga.edu/commodities/fruits/gapeach/pdf/copperformulations.pdf (http://www.caes.uga.edu/commodities/fruits/gapeach/pdf/copperformulations.pdf)

Title: Re: Blue cheese and copper rods ?
Post by: linuxboy on December 31, 2009, 01:20:34 AM

Driekus, yes, but that's when copper salts dissolve and are ionic. Copper metal by itself is rather unreactive, unless affected by acid, base, or mechanical action. Bacteria and mold toxity with copper happens through passive/active transport into the cell wall, and then the copper interferes with cell processes.

Title: Re: Blue cheese and copper rods ?
Post by: driekus on December 31, 2009, 01:37:22 AM

Sorry I should have clarified what I meant by copper toxicity induced by copper. Copper does form an oxide layer on the surface which is readily removed under damp acidic conditions. If you take a dull copper surface and wipe with acetic acid you will notice it shines. Im still fairly new to cheese making but as I understand it the interior of the cheese is relatively acid and thus any copper rods with an oxide layer could potentially deposit some copper into the cheese and act as a fungicide. I dont know if it would cause significant toxicity but I cant see it benefiting the penicillium.

Title: Re: Blue cheese and copper rods ?
Post by: linuxboy on December 31, 2009, 03:22:03 AM

Good point :); I think you're right.

Title: Re: Blue cheese and copper rods ?
Post by: michoutim on January 24, 2010, 03:39:26 AM

Thank you everyone! Food for thought!  :)