Cheesecloth embedded in pressed cheese

[Danbo]

I made a Gruyere today (recipe from "200 easy Homemade Cheese recipes").

The book suggest the following pressures:
Start with medium press at 10-20 psi
Continue firm pressure at 25-45 psi

I choose an 8 inch open hoop and placed it on a draining mat. I pressed it at 6 psi (300 kg). After an hour the cheese should be turned and redressed...

The cheesecloth was litterally embedded in the bottom of the cheese and the draining mat as well. It was not a pretty sight, when the cloth was removed...

As damage control I moved the cheese to a tomme mould (with a new cheesecloth) and increased the pressure to 10 psi (500 kg) for an hour. Luckily the cheese got the right shape from the new mould and looked fine.

The cheesecloth was still very hard to remove without damaging the cheese. Obviously the big pressure has a role in this but I didn't have the same problem yesterday when I made a cheddar.

Now the cheese is in the press again at 15 psi (750 kg) for 12 hours. This is the absolute maximum my monster lever press can survive - hopefully... Exciting...

Any good ideas on how to make the removal of the cheesecloth easier if it sticks to the cheese?

:-) Danbo

[Spoons]

Sticking to the cloth can be 3 things:

1. Try plyban cloth, it has smaller holes.
2. Ambient temperature a bit too warm. ideal temp should be around 21-22C, if it's warmer then the curd might become too soft.
3. For brined cheese; since the cheese is acidifying while being pressed, it's rind gets a bit too soft during it's crucial acidification curve in the press. This is quite common. Best thing to do is to gradually increase pressure and flip often for this type of cheese. Sailor Con Queso came up with a solution (search the boards, its there) you can spray your cloth with. I have a bottle in my fridge. If you start noticing some sticking issues, spray the cloth. The solution is vinegar based and is quite acidic, it will throw off your PH readings, but will prevent sticking.

I rarely use the spray, flipping often when the cheese is at it's high acidifying phase does the trick. 

[Stinky]

This happens to me pretty often with one of the pressing setups. The key is not pressing it too hard at the beginning, so the curd gets squeezed through and then pulls off parts. If you do tear pieces off, either get a new cheesecloth or move to a different part of the cloth.

[awakephd]

You might also re-visit your pressing pressures. I long ago concluded that the 25-45 psi in the 200 Easy book must refer to the pressure applied via a pneumatic press; the actual psi on the cheese will not be anywhere near that much, at least not unless the diameter of the pneumatic press is identical with the diameter of the cheese being pressed. I find cutting those numbers down by about 10 or so seems closer to what works well for me.

[Danbo]

Thanks for the advice - I really appreciate it! :-)

I took the cheese out this morning at it looks fine... I could slowly and carefully remove the cloth without damaging the cheese. I turned it and gave it half an hour in the press without cloth to perfect it...

I read some previous posts about psi etc. - I still don't get it... I can't see the difference between pressure generated by a pneumatic piston and a lever press piston. If the psi in the book refers to the pressure on the compressor side og the piston then the final pressure delivered to the cheese depends on the diametre of the piston cylinder. That diametre is not mentioned in the book and that makes it impossible to calculate the final pressure on the cheese. That fact leads me to believe that the PSIs mentioned in the book are actual press on the cheese. Coul be that the pressures are way too high anyway though...

Excuse me if my assumptions are way off - I just really want to understand this.

I do understand that if I put 50 pounds of weight on a cheese in a round 8" mould (area: 4x4x3,14=50,24 sqin) the cheese will be pressed at 50/50,24=1 psi

I made some calculation errors in my previous post - all the psi values should be divided by approx. 2 (I forgot to convert kg to pounds)...

:-) Danbo

[qdog1955]

Danbo----I could be wrong ----but I think you are confusing volume and psi-----a 2 inch cylinder may require 20 cubic feet of air to reach 10 psi (These are arbitrary figures) where as a 3 in. cylinder may require 75 cu. ft. of air to reach 10 psi----but they are both still 10 psi.
The final psi on the mold follower is the same whether it is generated by air, hydraulic or a bunch of bricks. Think of the cylinder as a working slave device, it's main purpose is to transfer the air pressure from a remote source and turn that pressure into a usable motion.
Qdog

[Danbo]

Hi Qdog,

Danbo----I could be wrong ----but I think you are confusing volume and psi-----a 2 inch cylinder may require 20 cubic feet of air to reach 10 psi (These are arbitrary figures) where as a 3 in. cylinder may require 75 cu. ft. of air to reach 10 psi----but they are both still 10 psi.

I don't think that the actual air volume on top of the piston in a pneumatic press have influence on the downward force. In other words you could have a short cylinder or a long cylinder that delivers the same downward force at the same pressure from the compressor.

So we agree that the volume is irrelevant - but the area of the piston inside the cylinder is what makes the big difference...

Lets say that you have a 25 mm cylinder and your compressor delivers 900 kPa (9 bar) then the force output would be 442 N or 45 kg / 99 lbs. On an 8" mould (50 sqin) that would be 99/50 = 2 psi.

If you have a 100 mm cylinder and you compressor still delivers 900 kPa (9 bar) then the force output would be 7069 N or 721 kg / 1590 lbs. On an 8" mould (50 sqin) that would be 1590/50 = 32 psi.

http://www.engineeringtoolbox.com/pneumatic-cylinder-force-d_1273.html

The final psi on the mold follower is the same whether it is generated by air, hydraulic or a bunch of bricks. Think of the cylinder as a working slave device, it's main purpose is to transfer the air pressure from a remote source and turn that pressure into a usable motion.

Exactly! That is why I get really confused when some books mention a psi-value at says that it is for a hydraulic press.....? I agree that it doesn't matter; Bricks, cars, lever-presses, pneumatic presses etc. - the output is what matters...

It seems to me that some books/sources are really confused when it comes to pressure... Or maybe I'm just way off myself. :-)

[John@PC]

Qdog, I went through Danbo's calculations and I think what he's saying is correct, mostly. 

I can't see the difference between pressure generated by a pneumatic piston and a lever press piston. If the psi in the book refers to the pressure on the compressor side og the piston then the final pressure delivered to the cheese depends on the diametre of the piston cylinder.

I would reword it to say "... the final pressure force delivered to the cheese (form's follower) depends on the diametre of the piston cylinder".  The other half of the equation is the diameter of the follower, and as far as I can tell Danbo's "pie-are-square" calculations are correct (50.24 sq. in for a 8" dia. form).

That fact leads me to believe that the PSIs mentioned in the book are actual press on the cheese.

I don't have the "200 recipe" book but I don't see how this couldn't be the case because 45psi on a 8" cylinder is astronomical.

Maybe it's the confusion between pressure, force and mass (weight).  I know Carlin's book always refers to a pressure in terms of force (weight) but she does usually state what the mold dia. is but then it's left to the cheesemaker to convert for a different diameter form.  Personally I don't care as I like to apply pressure "as required" rather by rote, but it would be nice if there was more consistency in the recipes for newer cheese makers as well as purests who want to duplicate as close as possible the classic methods of pressing.

[John@PC]

Sorry Danbo, I was drafting my reply while you were explaining (much more elegantly than I, I will add) the factors in pressing cheese, which is I would say right up there with understanding quarks and quantum physics.  You and Qdog are spot on, as usual .  A cheese to you for the nice round of cheese and for taking the time to explain.

[Danbo]

Hi John,

Thanks for your reply. It is great that we can share own knowledge - in this case though I would say that I have no previous experience with psi, force, pressure etc. so I might be wrong after all. It's been ages since I finished school... ;-)

Just a little quote from the book:
"If you wish to reduce the weight required, reduce the surface area by topping the follower with an object of smaller diameter. If the surface area is reduced to 6 square inches (for instance by placing a wooden disc of 2 inch diameter on top of the 4 inch follower), the weight required can be reduced [...]"

Hmmm... I am pretty sure that the cheese will not notice any difference because the weight is distibuted by the follower regardless of how large or small a wooden disc is used.......

I'm simply not experienced enough yet to be able to have a gut feeling when pressing. I just wish that different authors would do one of the following:
- Provide pressing PSI
- Provide weight for a specific mould diameter

:-) Danbo

[Danbo]

Just wondering.... If I stand on one leg on my bathroom scale would it say that I weigh the double? ;-)

[awakephd]

Hi John,

Thanks for your reply. It is great that we can share own knowledge - in this case though I would say that I have no previous experience with psi, force, pressure etc. so I might be wrong after all. It's been ages since I finished school... ;-)

Just a little quote from the book:
"If you wish to reduce the weight required, reduce the surface area by topping the follower with an object of smaller diameter. If the surface area is reduced to 6 square inches (for instance by placing a wooden disc of 2 inch diameter on top of the 4 inch follower), the weight required can be reduced [...]"

Hmmm... I am pretty sure that the cheese will not notice any difference because the weight is distibuted by the follower regardless of how large or small a wooden disc is used.......

I'm simply not experienced enough yet to be able to have a gut feeling when pressing. I just wish that different authors would do one of the following:
- Provide pressing PSI
- Provide weight for a specific mould diameter

:-) Danbo

Yes, this is one of the things in the book that led me to conclude that there are some problems in the psi given!

Let me see if I can give some further examples of psi vs. force:

Consider a cylinder of 2" diameter. Surface area of the end of the piston = π*1^2 (pi-r-squared) = 3.14 square inches. If 10 psi is applied to this cylinder, it has 10 pounds of force for each square inch; thus, it is exerting a total of 31.4 pounds of force.

Now double the size of the cylinder to 4" diameter. Surface area = π*2^2 = 12.56 square inches. The same 10 psi is now exerting a total of 125.6 pounds of force.

Now let's suppose that the 4" cylinder is pressing on the follower of an 8" diameter mold. Surface area of the follower = π*4^2 = 50.24. Does that mean that 10 psi on the cylinder equates to 502.4 pounds of force? No! Here is the crucial distinction: the 10 psi is not applied to the 8" mold; it is applied to the 4" cylinder ... which then presses on the mold. So the 10 psi is still exerting a total of 125.6 pounds of force (as calculated above). However, that 125.6 pounds is now being distributed across 50.24 square inches of surface via the follower, so the psi on the cheese is 125.6 / 50.24 = only 2.5 psi.

Clear as mud?

[qdog1955]

Danbo, seems you have a pretty good grasp on the situation. ---I almost had to laugh when I saw your mention of the small disc on top---as soon as I read that in the book-----I said to myself---"Self, that dog don't hunt"---- but maybe there is some mysterious force at work here I don't understand------so I ran down stairs to the cheese press----put a scale under the arm, and tried various size discs on top of a follower and low and behold ----no change what so ever.
  The moral of the story-----I always verify my, not so good math skills, by actually verifying the output with a scale----still have to do the sq. in. calcs.-----but we all must suffer some times
  Also wanted you to be aware----if your not already-----that the stroke length can be important in setting up your design----to short can make for a lot of inconvenience flipping and changing your molds.
Qdog

[John@PC]

Just a little quote from the book:
"If you wish to reduce the weight required, reduce the surface area by topping the follower with an object of smaller diameter. If the surface area is reduced to 6 square inches (for instance by placing a wooden disc of 2 inch diameter on top of the 4 inch follower), the weight required can be reduced [...]"
:-) Danbo

Thanks for furnishing the quote and your are absolutely correct in your analysis: that's dead wrong. Not only do they have the mechanics wrong a wooden disk 2" dia has an area of 3.14 (1x1x pi).  I think Andy addresses it in his reply and maybe Qdog, but it's a shame that something like that would make it past the proofreader.  Then again I don't have a proof reader and I could be all wet (been there, done that ). 

[lazyeiger]

Just a little quote from the book:
"If you wish to reduce the weight required, reduce the surface area by topping the follower with an object of smaller diameter. If the surface area is reduced to 6 square inches (for instance by placing a wooden disc of 2 inch diameter on top of the 4 inch follower), the weight required can be reduced [...]"

This of course as you have all pointed out is rubbish! I really do wish that authors would get their manuscripts proofed by a competent proof reader who when they encounter things they do not understand will always refer to an expert. ( i think I answered my own comment real proof readers are expensive because they check)

So how about this as an idea.  I do a lot of competitive shooting both rifle and hand gun. Powders are commonly weighed in grains, however benchrest shooters mostly all use a Harrel powder measure and very often use numbers of clicks on the measure to report charge. Most all the reloading forums insist that powder charges are reported in grains not clicks and moderators take down posts with clicks. This is obviously a safety thing.

so why not insist that all posters use weight for culture measurements and PSI for press measurements?

I don't understand how anyone can report Ph to 3 significant digits yet say they use 1/4 teaspoon of FD??

Sorry for the rant! My OCD is kicking in again!

Jon