What does late blowing look like?

[Mermaid]

And how soon will it occur? I'm attaching photos of some cheeses that have me curious because they seem ...well...poofy on the top and bottom in a way that only the very center of the wheel is touching the shelf. Is this because I wasn't good at turning the cheeses enough? (I was really bad before I learned to flip more often!) or is this something more sinister ?

Any advice is appreciated !

[Al Lewis]

If you used Flora Danica in those it could well be gas produced by those cultures.  It is a carbon dioxide gas producer, as are many other mesos so check the properties of your starter cultures.

[Kern]

As cheese ages it shrinks in a process that has a tendency to decrease surface area.  When a cylinder shrinks the "corners" (where the sides meet the top and bottom circles) try to "pull in' toward the center.  This has the effect raising the "corners" causing the bottom and top to dish and the sides to bulge.  If the cheese is flipped regularly then this effect should be more or less uniform and symmetrical.  I see this in your cheese photos and suspect that this is the cause.  This is not to say you couldn't have late blowing along with the shrinking but a "blown" cheese might be more irregular.  In the end you have to cut it in half to be sure of the cause.

[Danbo]

It looks like this: http://cheeseforum.org/forum/index.php/topic,13810.msg104618.html#msg104618

Late blowing is caused by clostridium tyrobutyricum spores in the milk. Pasteurisation kills clostridium but not the spores.

If cows are fed with ensilage the risk of clostridium is higher than if fed on grass/hay. I use something called Lysozyme when not using grass-/hay-milk. This minimizes the risk of late blowing.

Swelling of a cheese can be a sign of late blowing (if not intended with propionic bacteria etc.). The images below shows my late blower Asiago.

When I cut the cheese I could actually hear a a short sound of gas escaping. I smelled the cheese/gas and it smelled a like vommit. It's actually the smell of butyric acid produced by the clostridium.

The cheese had a big crack in the middle where the gas expanded, and that's also a typical sign of late blowing...

:-) Danbo

[Stinky]

From what I've heard, late blowing makes the cheese look like a sponge.

[Kern]

It looks like this: http://cheeseforum.org/forum/index.php/topic,13810.msg104618.html#msg104618

Late blowing is caused by clostridium tyrobutyricum spores in the milk. Pasteurisation kills clostridium but not the spores.

If cows are fed with ensilage the risk of clostridium is higher than if fed on grass/hay. I use something called Lysozyme when not using grass-/hay-milk. This minimizes the risk of late blowing.

I feel like I am running around CheeseForum posting little tidbits about Lysozyme as I learn more.    I learned this morning that it is all made in Europe from parts of chicken egg whites and that the rest of the egg is used to make ice cream, etc.  It takes about 10,000 eggs to make a kilogram.  It is available in the US from several sources including Scott Laboratories in Petaluma, CA (scottlab.com) and several wine and beer making suppliers offer it in small quantities.  Scott Labs calls their version Lysovin as their market is wine making.  I talked with a biologist there this AM who had heard of its use in cheese making but knew nothing more about it.  It is used in winemaking to kill lactic acid bacteria following malolactic fermentation.  She had no idea how it could kill clostridium tyrobutyricum and not effect thermophilic cheese bacteria as lysozyme goes after gram positive bacterial and both of these are gram positive.  But, it is widely used in Europe and especially Italy to help prevent blowing in long aged hard cheeses.  Lysolac, a Dutch company, has a web page showing how to use it and a little calculator to compute how much should be used. (http://lysolac.com/products.html).  The US and Eurpoean granular versions are the same (lysozyme hydrochloride) and are likely made in the same plant.

Other than possibly affecting thermophillic bacteria I see no downside in using lycozyme as directed above.  In fact, at a cost of about $40 per 150 grams I think it might be cheap insurance to make sure your long aged hard cheeses don't undergo late blowing.  The dosage level is about 1 gram per 4 gallons of milk so the cost works out to be about $ .08 per pound of cheese.

I'm still on a quest to learn how it can kill the bad guy without harming the good guys.    

[Danbo]

Good post Kern. :-)

My cheese looked like yours, but that doesn't mean that you're actually having a late blower.

I'd continue to age it and then see how it looks when it's ready. If it looks (and smells) like mine then it is likely to be bad.

:-) Danbo

[Al Lewis]

I have no idea is this is even close to right but might turn out be a reasonable solution.  At what temperature is clostridium tyrobutyricum killed?  Is it possible that the temperatures used to make thermophilic cheeses kills it and therefore it's not necessary in those cheeses.  I really haven't a clue but this might have some validity.

[Al Lewis]

Okay, turns out it's incubation temperature is 37°c.

[Danbo]

Clostridium Tyro... is killed during pasteurization But spores aren't. That's why it's late blowing - the spores comes to life over time. I don't know why meso-/thermophil cultures aren't affected much by Lysozyme, but I know that they are not.

[Al Lewis]

Another mystery for the ages!!  

[Mermaid]

I love how I can leave a question on this site, go to work, and come back to a bunch of thoughtful answers! Thanks everybody!

I used TA50 and LH100 , so doubtful that a ton of gas is producing inside the cheese. The cows are being fed nice hay-haven't fed any silage this year. 

ill also add that the cheeses doing this are small and all made in the same form . In the same bath I produce larger 25 pound wheels that are not exhibiting this shape shifting. So maybe it's just the form? Maybe I'm using too much Weight on the press?

I think probably from all your responses that this cheese will be just fine. I'll keep you updated!

[Al Lewis]

What cheese is it?

[awakephd]

From what I've heard, late blowing makes the cheese look like a sponge.

I thought that was more characteristic of early blowing -- ?

[GoudaGirl13]

Wow....reading about this scared me a little, especially since I mostly make long-aged cheeses. I googled Lysozyme and could only find medical and scientific references...not a single thing referring to cheese, wine, etc. I wonder if/where I could get such a thing in Canada. Hopefully not another "illegal" thing.....