Sorry if I've missed this in the Beaufort threads. I have not yet read the specific contribution of propionibacterium in Gruyère styles, because of the literature I've read, concerning the prop., all of them discuss "eyed cheeses," meaning, the large-eyed varieties such as emmental, with a warming period for the prop. to develop CO2 in addition to acetic and propionic acid and its other flavor contributions. I've not seen a specific discussion of the dynamics of propionics in a Gruyère, which though it can have eyes, is muted in eye development and, presumably, has little or no warming period, unlike, say, emmental.
I see from CHR Hansen that of two newish strains, one (PS-40) can grow at temps below 15C/59F, albeit slowly; its other featured strain, PS-20, requires a ripening above above 15-17C. I have Abiasa's "Propionic 50," don't know its environmental thresholds; but presume it will certainly be slowed, if not outright stopped, by maintenance in my cave (55F).
Sailor's Beaufort (https://cheeseforum.org/forum/index.php/topic,3556.0.html)recipe, and other discussions (I also recall Francois's noting the traditional use of mountain clover flowers to derive wild propionics (https://cheeseforum.org/forum/index.php/topic,1590.msg12489.html#msg12489)), employs propionibacteria. I was just wondering what contributions it (and by extension, most propionibacteria, as a general rule) makes, if any, under such an environment, absent the emmental-style warming period. Will it kick out acetic/propionic acid, though not CO2/eye formation? Other contributions (e.g., lipolysis/FFAs, peptidase/proline, under colder aging)?
I would also appreciate it if any of the masters would chime in.
I have two Gruyeres going now with Propionic S. in them. The last one produced so much gas that it ruptured the vacuum bag! (I have backed off the amount of Prop. S.) The cheese was delicious none the less!
They are both due for the warming period, but I'm apprehensive about taking them out of the cave.
Thanks in advance,
Knoal
How exacly does the gas itself escape, does it creat tiny stress fractures in the cheese while pressure builds in local gas producing "areas" or is the co2 gas molecules small enough to pass through the cheese stracture meaning the cheese is porus?
Too many variable to give you a good answer. generally, most of the metabolic products are still formed, but much slower.
Tomer, gas escapes through microfissures. If wheel is not pressed properly, it may even be porous enough.