Mould on sides but not tops/bottoms

[Knargle]

Pretty self-explanatory. I very often have this problem: the PC mould tends to grow much faster and better on the sides of the wheel than on the top or bottom. Sometimes the tops/bottoms never fully mould over. It gets so that by day 10 the sides are beautifully white and fluffy, and the tops and bottoms are still mostly bare or showing only the beginnings of mould.

I innoculate PC and GC together via spraying. I have the wheels on cheese mats raised up on plastic grids, all inside closed (but not completely sealed) plastic containers to maintain humidity. I'm pretty confident that lack of humidity isn't the issue, as where I am outdoor humidity is usually around 70-80% and a hygrometer inside the cheese containers gives me 90-99%. I flip once or twice a day.

I have come up with three hypothetical reasons and would value any input!

(1) This is a normal consequence of the fact that the bottom/top faces physically rest against the mat...? Perhaps the actual contact with the cheese mat causes slower growth...? Unlikely, I imagine.

(2) Perhaps my cheese mats are somehow slowing down the growth? I clean them with warm soapy water, then sanitize them with a couple sprays of a vinegar/tea tree oil solution, and then leave them to air-dry. Could it be that some residue from the vinegar solution is inhibiting the mould growth?

(3) I tend to salt the sides less than the tops (not that I salt the tops/bottoms too much - I definitely don't). Perhaps it's something in the salt? I use non-iodized, but there is the possibility that the salt producer I use has mis-labelled it...

Any help would be REALLY appreciated.

[awakephd]

Of those three options, I vote for #2. With my cams, the surface on the mat grows out with a grid effect (i.e., the pattern of the mat), but it does grow, quite exuberantly. Meanwhile, I don't salt the sides of my cams, just the tops and bottoms, but in general I still get an even coverage.

To be clear, I add my PC and geo to the milk along with the cultures, rather than spraying it on, but I wouldn't think that would change the behavior relative to the above.

I'm not familiar with tea tree oil, but it doesn't sound like something I'd want in contact with my cheese ...

[Andrew Marshallsay]

I find the same thing with Camembert. Instead of the vinegar and tea-tree oil, I use a bromine steriliser and air dry. This should not leave a residue.
I have always assumed that (3), most of the salt being applied to the flat surfaces, was the cause.
As for tea-tree oil (a good Aussie product), it is a disinfectant but not used internally. I would have thought that, being an oil, it might leave a residue.

[fattyacid]

Two things to keep in mind about Geo and PC:

1. They ARE salt sensitive, too much just on the tops and bottoms WILL stunt the development of your mold coat. If you are happy with the salt content of your cheese, continue to use the same amount but spread it over the whole cheese in one even coating.

2. They are acid sensitive too. So as the acid whey weeps from the bottom of the cheese it can inhibit mold growth. Adding a yeast such as KL71 or DH to your cheese milk or mold spray is important to accelerate the de-acidification of the cheese surface so your molds can grow. Almost all commercial artisan operations use this to get and early white mold bloom to help prevent mucor (black/grey fuzzy mold) and blue molds from getting a foothold. Yeasts will also lend a greater breadth of flavor to your cheese and traditionally have been present in this cheese archetype.

As far as washing your cheese making utensils, hot soapy water (Dawn is actually great for this), rinse and a chlorine bleach sanitizer is all you need. That is 1 teaspoon or 5 ml to 1 gallon cold water. Dip or spray your utensils and let air dry and you are good to go. You want all cheese making surfaces dry and free of ALL residue before use.

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