Bad Molds, Good Molds and Cured Meat – Pictures too

When it comes to curing meat especially dry-cured meat over a few months or more, the aspects of mold are one of the more challenging hurdles I’ve found in the beginning.

There’s not a lot of detail online or in many of the meat curing books that I’ve read about the good mold and the bad mold. So I hope this helps!

When I started doing dry-cured meats, I didn’t use any type of starter culture, which is one method for inoculating the curing chamber to create the right environment at the start.

Dry Cured Meat Penicillin White Mold
Blooming good penicillin mode on wild venison braesola!

I purely went down the natural path and willing to leave it in the hands of nature to decide whether things would progress or not. This was nearly 20 years ago!

Dry curing meat, specifically, has been going on for thousands of years, and good old-fashioned common sense played and plays a big part in successes and failures.

Common sense and logic and trusting you’re built in instincts about whether the food is good or not will help a lot. There is definitely now a lot more detachment from the natural world with all our glorious technologies including blogs!

Here is a summary first about molds and then I will tell you about what I have learned in relation to doing it at home.

What are Good and Bad Molds for Cured Meat? Good Mold is predominately white either powdery or fluffy. Certain Green colors can be good molds and related to the penicillin white mold also. Orange, Red needs to be removed, whilst black mold is definitely bad.

Purpose of Good Mold for Meat Curing

For many dry-cured meat projects, a minimum drying period is one-month plus. Normally it takes a couple of days or a week before you start to see blooms of mold on meat depending where it was hung (chamber/cellar etc. )or cold smoked.

Developing a good covering of powdery white penniclin mold on the outside of dry-cured whole muscle meat or dry cured salami is the goal.

Temperature, Humidity, Airflow, Existing Mold Culture, Lack of Light are the general environmental factors relating to this.

The white mold is a way of protecting the meat for certain recipes.

Other recipes such as Calabrian pancetta covered with pepper and chili/pepperoncino. External spices are used to deter the growth of mold.

Peppercorns & black (I think red, white etc too) pepper has antibacterial and antifungal properties.

The Funkiness

Dry cured meats can create what what some call the funk.

It’s really hard to describe the funk unless you have smelled or tasted it.

I think it would vary as well depending on the environment and how the moldable funk has developed. My thoughts are that the mold has a lot to do with the funk!

It’s probably part of the reason why over all these years I am still completely fascinated with dry curing meat, there are just so many subtle variations going on.

On a side note recently I’ve been thinking about cold smoking spices and using those for dry-cured meats. I’ll do some research around this and report back on this blog

The Flavor of Good Molds

Early development of white mold

Yes this is the same kind of mold that is used in medicine and hospitals.

It is that fluffy or powdery white mold known as penicillin.

It can be a purchased starter culture that you then inoculate the meat curing chamber with.

Or a naturally occurring white penicillin mold or good mold.

I would say the taste and smell is relatable to a type umami or savory.

One of my friends Lawrence, who I taught how to dry-cure meat absolutely loves the flavor of that white powdery mold on the outside of his wild pig guanciale.

Commercially dry cured meat with a bloom of white mold, you can see the healthy fuzz!

Molds and Using Your Senses

I talk a lot about using your senses in my online meat curing course, it is one of those obvious things but like many things, it’s good to be reminded of.

That is, we have an evolutionary naturally developed ability to work out from smelling and looking at food whether it’s going to be good for us or not (not all the time, but in most cases).

I am guilty of getting my nose right up next to the dry-cured meat giving it a big sniff. This gives me an indication of how things are going. I will continue to sniff all around that whole piece of meat!

The notorious bald headed salami sniffer – what a creature!

There is quite a bit of complexity that can happen with the smell of salami or of a whole muscle piece of charcuterie while it develops, again, this is why I find this craft so fascinating!

Natural Molds and Lab Mold

Using a lab starter culture, provided more consistency, as long as the conditions are right

Supposedly good old penicillin is floating around all over the place, and once you have finished curing with salt.

Your piece of meat has a chance, depending on your environment, that the naturally occurring penicillin will start on the meat. I’ve done this several times over the year with new DIY meat curing chamber I’ve put together.

But of course this is not guaranteed.

Commercial producers of dry-cured real salami, the stuff that takes months to make not the tangy acidic stuff that is made in a few days often are using this culture to make outcomes consistent.

They buy stuff and inoculate the salami or whole muscles meats themselves.

Mold 600 – Bactoferm

Home charcuterie makers and many other producers use CHR Hansen mold 600 for whole muscle meat curing innoculation.

There are plenty of starter cultures, but many are doing a similar function for say salami ie. acidification (a key tool for making salami preserved and create good outcomes).

Mold 600 is more about the outside of the meat whilst it’s drying.

I have it sitting in my freezer now, you can’t get it in every country be most countries in the western world. There are probably also other names it may have.

Guys have contacted me through the blog about trying to ‘scrap’ commercial traditional salami they buy to inoculate there own DIY curing chambers!

When I need to use it, I take half a teaspoon to half a cup of water. The water should ideally be distilled, but I’ve used filtered water which has worked as well.

Then you leave it for eight hours on the bench after giving it a bit of a shake, and then spread it in the chamber onto cured meat. Within a few days, you should start to see the spores of white mold developing.

Check out mold 600 from Amazon here.

Development of White Molds Over Time

So a lot of people just go on about the powdery mold but when you start learning more about dry-cured meats, you’ll notice that at the beginning you might get fluffy mold.

Array of Good Mold!

But really underneath that fluffy white mold is powdery mold it’s just the way that it grows.

Then down the line, as the mold gets older there is a green mold related to the spores of the white penicillin mold.

Dark green mold in a commercial environment down the bottom of Italy in Calabria.

Green mold is fine, but this is also a hog bladder for a spreadable salami called Njuda in Calabria, Italy. Casing is not consumed, well I don’t think it is!

Molds I Can Deal With

Now I have had some funky molds going on here are a few examples of things that were not good not bad but also what you don’t really want.

So I just wipe it off vinegar.

When it’s developing on a case think it’s not so much of the big deal, because you’ve obviously got some protection on the meat.

When you’re using no casing and going natural which I often am because I like to see exactly what’s going on. Using vinegar and wiping the mold off or even giving it a blast of cold smoked for a few hours can knock back some of this unwanted multi-colored mold.

Bad Molds – Black

Examples of fuzzy good mold, good green mold – and something that made me throw it out! 1 of 2 pieces I have thrown out over a few decades of making dry-cured meat.

There is a certain smell and a look that I’ve only had a couple of times over a few decades and that is the ominous black mold.

It kind of looked a little bit translucent and it was on some very exotic spices that I used, whether this was a factor or not I do not know.

Spices like star anise, coriander, cumin, and galangal were used. And there was this patch of what I would consider black mold.

The smell was very offputting and instantly my olfactory system said this needed to go straight into the rubbish bin.

Mold – Final Notes

Charcuterie Salumi Dry Cured Meat Picture
Charcuterie Salumi Dry Cured Meat – from my standard kitchen fridge. Only 1 month project, and no mold really.

I try really hard in my online meat curing course to go over mold and pictures and smells in the videos. But also at the end of the day, you need to go through and have your own experiences about what the good stuff should look like.

Always be on the side of caution and keep it safe! If you have to question it, it’s probably not worth risking it for the biscuit!

Put differently, if you had any doubts about anything you’re making it’s not worth getting sick from, and you should always be on the side of conservatism.

If you’re not completely happy with what you produce then throw it in the bin!

Cold Smoked Dry Cured Bacon, after 2 months in curing chamber. No mold because it’s been smoked and then hung to dry.


  1. Perhaps you can help. I am curing some pepperoni in UMI BAGS. Been in refrigerator since 3/22. It is now 0.71 its original weight. I noticed some white spots with green in the middle of each dot. Should it be discarded? New at this so a bit insecure. Do you have any advice?

    1. Author

      Hey there,
      often I find white and green completely fine, have a sniff! can wipe with vinegar if you want. You’ll find out when it’s done! Nothing is guaranteed with dry curing, thats why i love it!

      1. I am having the same thing. .79 weight loss using the dry aging bags, and I have a bunch of good white mold showing, but some spots 1/4 inch across that have a grey/green/blue color to them in the center of the dot. If you email me directly, I can send you a pic.

        1. Author

          Havent tried those bags, but been talking to some of those companies to see if I can test them. Your Nose will also indicate the molds that you want or not. Wipe with vinegar if its on the outside Cheers Tom

  2. Hello, I’m trying to make my first pancetta. After some time in the fridge, and a few days of my abscense it developed white mold like this:

    I asked around and some people told me to wipe it with some vinegar, after the process it looks like this:

    I’m not sure about the dark spots, do you think is okay or should i throw it out? The meat itself smells fine.
    Best regards

    1. Author

      Howdy Jan
      Always hard to judge this type of thing from pictures….
      How Does it smell? like you want to eat it or not?
      What method of curing the meat did you use, eq curing? %’s?, time in cure? how long in cure?
      Where was it dried and what temp, humidity and airflow?
      how firm was the meat after curing?
      There are plenty of cuts/crevices in the meat, did you put dry cure in these?
      White mold is of course what you want, so what did that white mold smell like?

      It doesn’t look like it has lost 30%+ weight, did it?
      I have a course also about whole muscle dry curing here
      All the best

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