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seogsoo
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Posted: 05 June 2012 at 2:57am | IP Logged Quote seogsoo

http://blog.naver.com/seogsooyie

Dear All

Please refer the attached my blog. I uploaded 4 pictures for some stain and one more for a bit different looking.

Is it fungus?

Regards

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kallenwe
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Posted: 05 June 2012 at 6:45am | IP Logged Quote kallenwe

Tell us a bit of what we are looking at!  Wetblue?  Plastic wrapped?  Days after production?  Temp?

Clearly there are liquid run marks in the stain.  Is it brown on the grain and red on the flesh sides of the sides?  Does not look fuzzy or fibrous like mold (fungus).  Could possibly be yeast (also a fungus), but that usually does not turn brown.  How soon or when does it appear, ie is there clean blue when finished with wet processing, but color appears later, or is color evident right out of the drum? 

Have you looked at it in a microscope?  Tried cultures?  Tested stain for sensitivity to acid/base/bleach/iron indicator/etc.  ?  



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seogsoo
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Posted: 05 June 2012 at 9:23pm | IP Logged Quote seogsoo

Dear Waldo

Sorry I also received as photos. But I also have seen many times. These phenomena happen by ageing of wetblue stock. And at more hot and humid region.

It also happen on flesh side but not so obvious. It seems like iron lust but can not be washed out by acids

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dengwja
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Posted: 06 June 2012 at 2:25am | IP Logged Quote dengwja

Especially after hot storage!

The stains always on the edge of wetblue.

I ever saw such problems.

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dengwja
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Posted: 06 June 2012 at 2:30am | IP Logged Quote dengwja

I have more pics, however, it is not so easy to upload in this forum.

The points need to pay attention:

1, mould

2. iron stains

3, hot storage

4, fat content

5, etc.

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kallenwe
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Posted: 09 June 2012 at 4:04pm | IP Logged Quote kallenwe

While I do not trust any observations but my own when it comes to molds, yeasts and spews (because they are usually reported inaccurately), I will say categorically, if the stain develops in the pile, after processing (it is not present on the stock when piled), then it is likely yeast or mold.

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faizalahmad
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Posted: 10 June 2012 at 8:37am | IP Logged Quote faizalahmad

its problem with molases reduced chrome were the stain appeared on exposure to atmosphere. try using bisulphite reduced chrome. the red stain on flesh seems to be fungal stain.

faizal
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cbblackie3
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Posted: 10 June 2012 at 6:25pm | IP Logged Quote cbblackie3

My guess is iron stains.  They should be easily rempoved in coloring.  Do you see this stain after coloring and drying?

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seogsoo
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Posted: 10 June 2012 at 11:58pm | IP Logged Quote seogsoo

Yes I also gueesed as iron stain. But my friend said "can not be removed by oxalic acid"

I will confirm it again.

molases or dextrose reduced chrome also make sense.

Thanks to all

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kallenwe
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Posted: 11 June 2012 at 7:19am | IP Logged Quote kallenwe

Iron should be very easy to confirm or disprove.  You can simply cut off some of the stain surface, ash it in a muffle furnace (iron will remain in the ash as a rust colored residue), or put a drop of HCL on the stain followed by a drop of 5% potassium ferrocyanide (bright prussian blue color is easy to see if iron is present).  Of course there is always analytical approach using colorimetric or AA or ICP. 

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