Curing meat - worried about botulism!

[Ciaran]

Hey guys,

I'm pretty new to cured/dried/preserved meats, certainly have never preserved anything for >1 week.

I recently began a violino di capra with lamb instead of goat leg. Basically it's a dry cured leg left to dry for~ 3 months.

I used a recipe from the River Cottage book on charcuterie and the author basically said he and his restaurant never bother with nitrates, that he didn't think they were necessary if you follow good practice. So I didn't use any in my cure, which was basically ~60g PDV salt, 100g brown sugar and various herbs.

I cured the meat for 3 days in a vacuum locked bag, draining, cleaning and reapplying a fresh dry cure half way through.

I then made what I'm worried is the major error. I put the leg in my fan oven and left it for ~5 days there with the heat turned off and just the fan on. This worked really well for the drying, but on reflection I think the temperature inside was often >18C at times during these 5 days.

I have now hung the leg in the attic which is cool, dry and airy.

The meat looks fine, it's started to get little patches of penicillium already, it's nice and dry and smells great.

But I'm worried about botulism and that the 5 days at a higher than desired temperature might have kicked started any inside the meat.

On the other hand I have also read that botulism is only really a risk in things that involve grinding/mincing/slicing the meat, and that whole cured cuts don't have a risk of botulism because the inside of the meat won't have been exposed to the spores and so nitrates aren't needed at all anyway.

Just wondering if anyone can give their advice on this matter!

Thanks guys.

Here's a pic before the cure and as it is now:

 

[Addie]

I don't have an answer for you, but I do want to welcome you to DC. I am sure someone will come along with and answer and some sound advice.

 

[Mad Cook]

Hey guys,

I'm pretty new to cured/dried/preserved meats, certainly have never preserved anything for >1 week.

I recently began a violino di capra with lamb instead of goat leg. Basically it's a dry cured leg left to dry for~ 3 months.

I used a recipe from the River Cottage book on charcuterie and the author basically said he and his restaurant never bother with nitrates, that he didn't think they were necessary if you follow good practice. So I didn't use any in my cure, which was basically ~60g PDV salt, 100g brown sugar and various herbs.

I cured the meat for 3 days in a vacuum locked bag, draining, cleaning and reapplying a fresh dry cure half way through.

I then made what I'm worried is the major error. I put the leg in my fan oven and left it for ~5 days there with the heat turned off and just the fan on. This worked really well for the drying, but on reflection I think the temperature inside was often >18C at times during these 5 days.

I have now hung the leg in the attic which is cool, dry and airy.

The meat looks fine, it's started to get little patches of penicillium already, it's nice and dry and smells great.

But I'm worried about botulism and that the 5 days at a higher than desired temperature might have kicked started any inside the meat.

On the other hand I have also read that botulism is only really a risk in things that involve grinding/mincing/slicing the meat, and that whole cured cuts don't have a risk of botulism because the inside of the meat won't have been exposed to the spores and so nitrates aren't needed at all anyway.

Just wondering if anyone can give their advice on this matter!

Thanks guys.

Here's a pic before the cure and as it is now:

Whilst I have done a fair bit of meat curing I have to admit that I've never cured a leg of lamb. However, I would be more than a little worried about that temperature. 18 deg C is equivalent to 64-65deg F. temperature and a bit too warm for safety (That's one of the reasons why preserving meat by curing was traditionally an autumn activity). My book recommends no more that 60 degrees - which may sound a bit nit-picking but it could be the difference between doing it properly and wasting the leg of lamb.And the temperature needs to be fairly constant.

Bear in mind that botulism is not the only food poisoning organism there's listeria and e.coli to name but two others.

Your sources are correct in that nitrates are not necessary for the actual preservation of meat (although some "authorities" on the subject still say they are) but a tiny amount helps the colour of the finished meat. Grey-ish meat may taste fine but it appeals to the eye more when it's pink-ish. We eat with our eyes... "Tiny" being the operative word in the use of nitrates. A lot of old recipes that are scaled down from recipes which would have been used when the whole village salted their pigs en masse can be a tad inaccurate in the amount of saltpetre or it's modern equivalents and can taste unpleasant.

 

[taxlady]

I'm no authority, so I don't know and take what I say with a grain of salt. Botulism only grows in anaerobic conditions or maybe it only makes the toxin in anaerobic conditions. I don't know if there are parts of the meat that have no oxygen and could allow botulism to grow and produce toxin. I strongly doubt it.

 

[Ciaran]

Whilst I have done a fair bit of meat curing I have to admit that I've never cured a leg of lamb. However, I would be more than a little worried about that temperature. 18 deg C is equivalent to 64-65deg F. temperature and a bit too warm for safety (That's one of the reasons why preserving meat by curing was traditionally an autumn activity). My book recommends no more that 60 degrees - which may sound a bit nit-picking but it could be the difference between doing it properly and wasting the leg of lamb.And the temperature needs to be fairly constant.

Bear in mind that botulism is not the only food poisoning organism there's listeria and e.coli to name but two others.

Your sources are correct in that nitrates are not necessary for the actual preservation of meat (although some "authorities" on the subject still say they are) but a tiny amount helps the colour of the finished meat. Grey-ish meat may taste fine but it appeals to the eye more when it's pink-ish. We eat with our eyes... "Tiny" being the operative word in the use of nitrates. A lot of old recipes that are scaled down from recipes which would have been used when the whole village salted their pigs en masse can be a tad inaccurate in the amount of saltpetre or it's modern equivalents and can taste unpleasant.

Hmm. Well it was only at that temperature for a couple of days, but yeah I take your point.

It's currently hanging at about 16-17 degrees during the day, much lower at night, I can't seem to find anywhere cooler to put it.

I'm willing to take the risk with the other possible nasties especially as they are easier to spot/smell, but I don't want to take any risk with botulism.. That can very easily be game over and there are no clues it's there

I'm just wondering if in this case there is any particular risk of botulism in particular. Being anaerobic I understand it can't grow on the surface, so the question is, could it be present inside the meat and growing in there?

I didn't cut the meat, it's one solid piece. Presumably a cure with nitrates in it wouldn't have gotten into the centre of the meat anyway?

My book says that the risk of botulism is just with things like salami and saucisson where you first grind and then dry the meat, as that can potentially introduce spores into the meat, and that there is "no risk" with whole cuts like coppa and whatnot...

But I just wanted to check if that's actually true and not cavalier

 

[CraigC]

Hmm. Well it was only at that temperature for a couple of days, but yeah I take your point.

It's currently hanging at about 16-17 degrees during the day, much lower at night, I can't seem to find anywhere cooler to put it.

I'm willing to take the risk with the other possible nasties especially as they are easier to spot/smell, but I don't want to take any risk with botulism.. That can very easily be game over and there are no clues it's there

I'm just wondering if in this case there is any particular risk of botulism in particular. Being anaerobic I understand it can't grow on the surface, so the question is, could it be present inside the meat and growing in there?

I didn't cut the meat, it's one solid piece. Presumably a cure with nitrates in it wouldn't have gotten into the centre of the meat anyway?

My book says that the risk of botulism is just with things like salami and saucisson where you first grind and then dry the meat, as that can potentially introduce spores into the meat, and that there is "no risk" with whole cuts like coppa and whatnot...

But I just wanted to check if that's actually true and not cavalier

You need a designated, tested, temperature and humidity controlled environment for curing. I would suggest that if you are not willing to do things properly, don't bother or at least don't let anyone but yourself eat it. Charcuterie is not something that should be done without proper attention to detail.

 

[RPCookin]

You need a designated, tested, temperature and humidity controlled environment for curing. I would suggest that if you are not willing to do things properly, don't bother or at least don't let anyone but yourself eat it. Charcuterie is not something that should be done without proper attention to detail.

And yet they have been curing meats that way since hunting was invented. Granted that maybe not all of those preserved meats made it to the table safely, but it doesn't necessarily require the absolute care that you propose. Hunters often hang deer and elk in the garage for up to 2 weeks before butchering, and I know that when I lived in Montana we didn't always get perfect fall weather for aging the meat (I've seen temps in the 90's in mid September). Never seemed to kill anyone.

I grant that he needs to pay attention to what he's doing, and it seems that a smaller cut like that left at a temperature in the mid 60's for two days might be a bit much (and I really don't know if it's a deal killer or not). I don't see any reason why he can't try again in the fall when the weather is more likely to be more cooperative.

 

[taxlady]

Is it possible to get a lab to test a sample of the meat for microorganisms?

 

[Ciaran]

You need a designated, tested, temperature and humidity controlled environment for curing. I would suggest that if you are not willing to do things properly, don't bother or at least don't let anyone but yourself eat it. Charcuterie is not something that should be done without proper attention to detail.

I followed the instructions, which asked only for an environment between 10-18C, and I'm just saying that it's likely that it's possible it was 2-4C more than that intermittently for ~5 days. My question is whether or not that means I now need to throw this away, and specifically if there is an increased risk of botulism or if, as the book says, there is no risk of botulism in whole cuts.

Is it possible to get a lab to test a sample of the meat for microorganisms?

No not really. Most bacteria are going to be pretty obvious anyway, making the meat smelly/mealy, but it's the botulism I'm worried about, that won't show any signs and even in tiny quantities is very toxic.

 

[medtran49]

And yet they have been curing meats that way since hunting was invented. Granted that maybe not all of those preserved meats made it to the table safely, but it doesn't necessarily require the absolute care that you propose. Hunters often hang deer and elk in the garage for up to 2 weeks before butchering, and I know that when I lived in Montana we didn't always get perfect fall weather for aging the meat (I've seen temps in the 90's in mid September). Never seemed to kill anyone.

I grant that he needs to pay attention to what he's doing, and it seems that a smaller cut like that left at a temperature in the mid 60's for two days might be a bit much (and I really don't know if it's a deal killer or not). I don't see any reason why he can't try again in the fall when the weather is more likely to be more cooperative.

Aging and curing are totally different things. However, improperly aged catch is why many people are turned off of venison and other wild game.

Curing generally takes several days to a week or so for the initial process of adding spices/salt/herbs/sugar/etc., then 3-4 weeks of hanging for even a small piece of meat, and can take many months depending on what you are curing.

As far as curing, if you get the proper conditions set up beforehand, then it really doesn't require a lot of care, just checking, feeling, weighing to see how your product is progressing about once a week. When I did the bresaola and the duck breast prosciutto, I got everything set up and tested a few days before, checking several times a day to make sure that the temperature and humidity stayed in the correct range, which was temps 55 to 60, no higher, preferably right in the middle of that range. I don't remember the humidity percent off the top of my head, would have to check the books but you also have to have proper humidity. Too dry and you risk the outside of the meat drying out too fast, getting hard, and the inside basically ending up raw and rotted. Too moist and you get the bad kind of mold that WILL make you sick.

I read this thread early this a.m. and didn't answer until now, but my first thought was throw it out.

 

[taxlady]

...

No not really. Most bacteria are going to be pretty obvious anyway, making the meat smelly/mealy, but it's the botulism I'm worried about, that won't show any signs and even in tiny quantities is very toxic.

Botulism is caused by a microorganism.

 

[Ciaran]

Aging and curing are totally different things. However, improperly aged catch is why many people are turned off of venison and other wild game.

Curing generally takes several days to a week or so for the initial process of adding spices/salt/herbs/sugar/etc., then 3-4 weeks of hanging for even a small piece of meat, and can take many months depending on what you are curing.

As far as curing, if you get the proper conditions set up beforehand, then it really doesn't require a lot of care, just checking, feeling, weighing to see how your product is progressing about once a week. When I did the bresaola and the duck breast prosciutto, I got everything set up and tested a few days before, checking several times a day to make sure that the temperature and humidity stayed in the correct range, which was temps 55 to 60, no higher, preferably right in the middle of that range. I don't remember the humidity percent off the top of my head, would have to check the books but you also have to have proper humidity. Too dry and you risk the outside of the meat drying out too fast, getting hard, and the inside basically ending up raw and rotted. Too moist and you get the bad kind of mold that WILL make you sick.

I read this thread early this a.m. and didn't answer until now, but my first thought was throw it out.

Thanks for the reply!

Is there any point in waiting and seeing how the meat goes or shall I just throw it away now?

Also, what is the meat possibly being at a slightly higher temperature for those few days likely to have caused? Are we talking about any specific bacteria and how about botulinum in particular? Is it true that whole cuts of meat don't have a risk of botulism?

In general, say you're curing a leg of pork or something, and a month in you go away for a few days and when you come back you realise that the place you stored it in was say, 65 F, do you then throw away the meat and start again?

Last question, my book said that up to 65 F is fine, is this wrong?

Botulism is caused by a microorganism.

I know.

 

[taxlady]

Botulism is caused by a microorganism.

...
I know.

But if there is no Clostridium botulinum bacteria, there isn't any botulism.

Or are you worried that there could be Clostridium botulinum bacteria in some other part of the meat, elsewhere than where the sample is taken?

 

[Ciaran]

But if there is no Clostridium botulinum bacteria, there isn't any botulism.

Or are you worried that there could be Clostridium botulinum bacteria in some other part of the meat, elsewhere than where the sample is taken?

Sorry yeah that's what I was thinking, given that it's so toxic even in such tiny amounts.

 

[Steve Kroll]

I'd worry more about listeria than botulism, which is pretty rare, however, given all the salt that's used in cures I think you're at pretty low risk of contamination from anything. People have preserved meat this way for thousands of years, and not always under the most ideal conditions. But today we live in a very antiseptic age, where folks get weird whenever you even talk about doing stuff like this.

If it were mine, I sure wouldn't throw out a nice leg of lamb.

I'll also add that I would certainly try it myself before offering to anyone else. You know... just to mitigate the chances of getting hit with any lawsuits.

 

[Ciaran]

I'd worry more about listeria than botulism, which is pretty rare, however, given all the salt that's used in cures I think you're at pretty low risk of contamination from anything. People have preserved meat this way for thousands of years, and not always under the most ideal conditions. But today we live in a very antiseptic age, where folks get weird whenever you even talk about doing stuff like this.

If it were mine, I sure wouldn't throw out a nice leg of lamb.

I'll also add that I would certainly try it myself before offering to anyone else. You know... just to mitigate the chances of getting hit with any lawsuits.

Lol either that or it's time to get a pet rat!

 

[taxlady]

Lol either that or it's time to get a pet rat!

Well, a pet something. Rodents can tolerate toxins that we can't.

 

[Ciaran]

Just to also say that since taking the meat to the attic to hang I have been the taking temperature of the meat with an infrared sensor and it's max 17 min 10 currently.

Can anyone comment specifically on the botulism issue?

And is it worth just keeping the meat for a few weeks and seeing how it develops or will any issues of contamination be invisible so it's just as well to throw it away now?

 

[Kayelle]

Just to also say that since taking the meat to the attic to hang I have been the taking temperature of the meat with an infrared sensor and it's max 17 min 10 currently.

Can anyone comment specifically on the botulism issue?

And is it worth just keeping the meat for a few weeks and seeing how it develops or will any issues of contamination be invisible so it's just as well to throw it away now?

I think you've answered your own question. How much would you enjoy tasting it after you've written your will?

 

[Ciaran]

I think you've answered your own question. How much would you enjoy tasting it after you've written your will?

I'd quite like some specific advice before I chuck out this £20 piece of meat, rather than just sound bites!

I will throw it away if needs be I just would like someone to explain specifically if and why the meat is now unsafe.

For example, my main concern is botulism and this book says there is no risk of botulism in whole cuts of meat, is this true? And if the meat was a few degrees over 18C for a few days before being returned to safe temperature ranges, specifically what will this have done to the meat?

For example, if botulism is truly not an issue then would not the other possible contaminants eg. e coli cause quite obviously mealy/off meat, particularly after a couple of weeks? How long does hanging meat need to be outside temperature range for there to be issues/risks, and what are they exactly?

I can't find these answers in the literature I have so I am asking here, but I need a bit more than "better safe than sorry" or "will it taste good when you're dead" etc.

Something more along the lines of "there is a chance that at x temperature, y micro-organism that is present in the meat even without it being sliced/minced will have been active and contaminated the inside of the food even in that time".



medtran49 mentioned drying too quickly, this might be an issue because the fan did a pretty good job of drying, maybe too good. The surface is already dry as a bone.