Is it mold?

[sukufe]

Hi there. It's my second brew and it goes like this. I wonder if it is mold or not? Can anyone with experience help me?

 

[IslandLizard]

The small green/gray specs floating on top? Or the large gray area on your scoby?

Doesn't look like mold. Mold usually floats and is furry.

 

[sukufe]

The small green/gray specs floating on top? Or the large gray area on your scoby?

Doesn't look like mold. Mold usually floats and is furry.

The green/gray area contacts with the fluid. I mean it's bottom side of the scoby.

 

[IslandLizard]

I've seen similar discoloring in scobies. I don't know what causes it, but think it's normal.

Molds need oxygen to grow, that's why they grow on the surface and along vessel walls. Anything below the surface is low of oxygen, as well as low pH.

Hopefully someone else can confirm this.

 

[sukufe]

I've seen similar discoloring in scobies. I don't know what causes it, but think it's normal.

Molds need oxygen to grow, that's why they grow on the surface and along vessel walls. Anything below the surface is low of oxygen, as well as low pH.

Hopefully someone else can confirm this.

Thanks for your help.

 

[RPh_Guy]

Hopefully someone else can confirm this.

I'm 99.9% sure these commonly seen discolored pellicles are not from mold growth.

It is possible for mold to grow in an air pocket under the pellicle, but that would almost certainly be accompanied by visible growth on the surface as well. Furthermore mold comes in a variety of colors but I haven't ever seen green or red discoloration. To me that provides additional evidence that the discoloration is not caused by mold, because it would present in a variety of colors. Lastly, mold growth on a surface tends to radiate from a central point, with the highest concentration of growth in the center. That's not what we see in most cases like this.

I suspect discolored pellicles like these are simply due to oxidative browning.

 

[sukufe]

I'm 99.9% sure these commonly seen discolored pellicles are not from mold growth.

It is possible for mold to grow in an air pocket under the pellicle, but that would almost certainly be accompanied by visible growth on the surface as well. Furthermore mold comes in a variety of colors but I haven't ever seen green or red discoloration. To me that provides additional evidence that the discoloration is not caused by mold, because it would present in a variety of colors. Lastly, mold growth on a surface tends to radiate from a central point, with the highest concentration of growth in the center. That's not what we see in most cases like this.

I suspect discolored pellicles like these are simply due to oxidative browning.

Thank you very much for detailed information. I’m grateful for your answers guys.