Popcorn jar. Contamination?

My popcorn jar sat in a spot with some mild sunlight (nothing too extreme) for a few days. I think the kernels dried out a bit because of it, which seems to have drastically slowed down the mycelium progress. Since the top section is noticeably drier, the healthy mycelium hasn't really colonized it normally. Instead, a dry, matte white-looking patch has formed over the top kernels.

Does this look like contamination to you, or is it just dried-out, stressed mycelium?

I'm thinking about shaking the jar. Should I go ahead and do a break-and-shake right now, or should I give it some more time?

Thanks in advance for the help!

Hello! Do you see tiny grayish beads here?

When I zoom in I see tiny gray powdery beads on a stem

It looks like early pin mold to me. See more examples here: Black Pin Mold

Let's give this jar 2-3 more days and check it again to make sure it's this type of mold. Don't shake it!

Also your corn looks too dry. How long did you simmer it before sterilization?

Thanks for the input! I'll hold off on the B&S and post an update in a few days. To answer your question: I simmered the corn for 30 mins and PC'd at 8 psi for 3 hours (including venting). I've had successful harvests with this exact same tek before, and the other 6 jars from this batch are doing fine. Note that all the jars caught some mild sunlight for a few days. I think that caused moisture loss, especially at the top. The mycelium colonized the bottom fine but stalled up top because it's too dry. Btw, we are on Day 49 with zero B&S. Do you think there's any chance this is just dried-out, stressed mycelium rather than mold? Here is how the other jars from the same batch are looking:

All the other jars look good, I don't see any signs of contam or questionable areas 🧐

Yeah, the grains look dry. Usually I simmer corn for 50-60 mins before PCing and it takes ~2-3 weeks for full colonization. Corn is a forgiving grain, it's hard to overcook it. So don't be afraid to simmer it longer. Your mycelium will be much happier, faster, and less stressed with dehydration

You can remove uncolonized grains on the top (I mean your healthy jars, ofc) and use the grains covered with mycelium for the next step (spawn to bulk). Yes, you can do it! In your case, this would be better than B&S and making the myc keep struggling in a dry grain. Myc needs moisture, and it will spread through the bulk very fast ;-)

I only simmer for 30 minutes because my PC cycle is 3 hours long (since it's 8 psi), and the corn continues to cook and crack from the steam inside the PC. I'll definitely try simmering it longer next time though, or I might just give brown rice a shot. Regarding the healthy jars, you mentioned removing the uncolonized top grains and using the rest for S2B. I feel like it's risky to birth a jar that isn't 100% colonized. I'm really worried about getting contam if I do that.

It’s risky to use UNCOLONIZED grains. But if you remove the uncolonized part, it’s absolutely safe to use the rest of the healthy spawn for S2B.

I always suggest that growers check the spawn before mixing it with bulk and toss any bald grains. Even if the jar looks completely colonized, sometimes there may still be bald areas, and you can only find them after opening the jar and breaking up the spawn for S2B.

In your case, tossing the top layer is even easier.

Of course, you can do B&S, but there’s no guarantee that the dry grains will colonize. Then you’ll have to pick those bald grains out from the rest. Or, if you do S2B with uncolonized grains, that may be more risky.

Anyway, the choice is yours :-)

I went ahead and did a B&S on all the jars except for the contaminated one. Thanks for all your help and advice!

I'll keep updating this thread with the progress as things move along. Take care for now!

Good! Thanks for the update. Looking forward to the next ones🤞