Blue mold growth on manchego

[Kjeffus]

I made this Manchego style about a week ago and I've started getting some blue molds growing already. Is there anything I can do to get rid of them? Are they going to ruin my cheese?! I can't believe how aggressive blue molds are I thought I had been careful to keep the ones I'm making separate.

[awakephd]

As you've discovered, blue mold can be incredibly invasive - and it doesn't have to come from cheeses you've made; it is often present "in the wild" in the environment. (Unfortunately, the wild blue rarely provides the kind of blue flavor you might be looking for in a blue cheese.)

In my experience, once the blue is started, you will never get rid of all traces; at the very least it will leave behind some discoloration. But never despair, there are ways to keep it from damaging what you are trying to achieve:

1) Regular cleaning of the rind, using salt and vinegar and/or white wine - the salt provides a grit to help scrub off the blue. Note that you can get too aggressive with this; if the rind is still relatively thin and/or soft, you can disrupt the rind. Given the ridges in your Manchego mold, you may need to use a brush to do your cleaning. For best results, clean the rind at least once per day.

2) Dry out the rind - if the rind gets dry enough, the blue will not find it suitable for growth. Obviously you need to keep the rind clean while it is drying out, and you don't want to rush the drying, or you'll get a crack - and when the blue gets in the crack, it is REALLY hard to deal with.

3) Out-compete the blue - rather than 1 and/or 2 above, you can introduce b. Linens to the cheese, ideally at the beginning of the affinage before the blue has had a chance to show up. If you get a good smear of b. Linens going, it will out-compete the blue (or any other mold). Once it is well established, you can then dry it off, leaving an attractive red coloring on the outside of the cheese. Note that the longer you keep the smear going, the more it will contribute to the taste of the cheese, which may not be what you want - but if you only let it get well established, and then dry it off, it will give you color and protection with only a small (but positive) effect on the taste.

4) Seal it - blue mold requires oxygen to grow, so if you can deny it the oxygen, you can prevent it from growing. If blue mold has already gotten established, you will of course need to clean the rind as thoroughly as possible before sealing (though you will likely have some dark spots left behind). The classic way to seal a cheese is with hot wax, and if the wax is hot enough, it will help to kill off any mold - but note that if you get the wax too hot, it can catch fire. The easy/modern way to seal a cheese is with a vacuum-bag food sealer. A cheese sealed with either wax or vacuum bag will age differently from an unsealed cheese; part of that is often the fact that an unsealed cheese will have some amount of mold on it, and part is the way it continues to dry out. But a sealed cheese DOES age, and can age very well indeed.

5) Coat it with spices - in a sense this is a variation of #3, but somewhat less effective. If you coat the cheese with olive oil and paprika (or smoked paprika if you want a lovely smokey flavor) BEFORE any blue sets in, it can keep the blues away; if the blue is already established, it may or may not be able to keep it at bay.

And of course, with all of the above, individual conditions will vary, so you will need to experiment to see what works best in your environment.

[Kjeffus]

Thank you! I am going to try the salt/vinegar method and see how this works. I will try and report back hopefully I can keep them at bay I was hoping to do a brushed natural rind this time around

[Kjeffus]

I'm wondering, do I need to clean and sanitize my cheese cave since I'm having this wild blue mold appear? I would hate to continue having this issue with future cheeses!

[mikekchar]

My current experience is that geotrichum candidum will generally keep the blue away.  There are a couple of other yeasts that do this as well.  I believe this is called "rind pre-conditioning".  Essentially, the first month is the most vulnerable time for the cheese.  There is a lot of food that the mould likes to eat that's available.  Yeasts like geo compete for the same food, so if you get them working well, they will keep the mould at bay.  After about a month, the food source dries up.  Blue will still show up, but it's relatively trivial to keep it under control at that point.

With a manchego mould, this is a bit tricky, though.  First, one of the secrets I've discovered about dealing with blue is to keep any sharp angles on the surface of the cheese at a minimum.  The smoother the rind, the less the blue likes it (and the more the yeast likes it).  The manchego mould intentionally has all those crevices, so I'm inclined to believe that some blue is inevitable.  The other potential problem is that geo and other fluffy white yeasts are not usually present on a machego.  However, you can get them going and then clean them off after a month.  But I think this isn't really traditional.

For this cheese, I think it's definitely going to be salt/vinegar wash.  It will definitely kill the blue, but it will keep coming back.  Eventually, when the rind hardens and the food runs out, it will be a lot easier to control.  You will get some staining in the crevices, but that's totally natural for a manchego.  You can also oil the cheese once a month or so.  This will help to keep the blue from coming back.

For other cheeses, I highly recommend trying geo coverage and keeping the rind as smooth as possible (no stippling from the mould, no crevices or marks or cracks).  You can buy a geo that doesn't go brainy on you.  My local yeast (whatever it is) works well and doesn't go very brainy.

For getting the geo going, it's important to realise that geo is only tolerant of salt up to 4%, so if you ever wash with a brine, keep it below 4%.  Also, I've been waiting a day after brining to introduce the geo (I just rub it on from another cheese) and this seems to help it establish quickly.  Usually I get full coverage in a couple of days.  The schedule for my last 4 cheeses was: Day 1 brine.  Day 2 rub geo on the cheese.  Day 3 Flip.  Day 4 Flip.  By Day 4 I have tufts of white.  At that point, you can wash the cheese with brine (or a pure salt rub) and magically the next day it rebounds with huge geo growth.  By Day 6 it is white and fuzzy.

Once you get to the white and fuzzy stage you can either leave it alone completely (just flipping it every day or two) or you can brush it to get a brushed rind effect.  But blue will *not* show up as far as I can tell.  I should also mention it helps to keep the humidity *really* high.  My geo/yeast (whatever it is) seems to like it up above 90%.  I have to dry out my maturation boxes every day.

Anyway, I've only done 4 cheese like that, but like I said it's practically magic.  Hopefully it will work for you too.