Recipe Scaling - Time & Pressure?

[Gina]

Hi all, I'm new at cheese making but have been reading here voraciously. Lots of really good information and all the oh-so helpful photos.

The other day I made my first real cheese - a manchego from 3 gallons of milk instead of the one gallon in the recipe from this forum. I am pleased with how it seems to have turned out, but taste might be another matter. 

I do have a question about this and other cheeses: When you double or triple a recipe, is there a formula for increasing the time and pressure in the press?

Thanks

[MarkShelton]

I don't change the amount of time pressed, but you do need to change the pressure. The change in pressure is proportionate to the increase in surface area of the cheese. For example, say you normally use a 4" mold and press with 30#. If you increase the batch and use  a 6" mold instead, you would need to use ~67# to have an equivalent pressure (the surface area of a 4" mold is 12.6 square inches compared to 28.3 square inches for a 6", thus the 6" has 2.8 times as much surface area, so 2.8 times the weight.)

[Sailor Con Queso]

Gina - here is a simpler explanation

If you double a recipe, time and pressure do not change, IF you use the same mold that you used for the smaller batch. However, if you use a larger mold, then yes you need to increase pressure. Time stays the same regardless. As the size of a mold increases, the weight that you are pressing with spreads out over a larger surface area so you have to compensate for that. There are 2 distinct schools of thought among cheesemakers here on the forum.

The first is the "Big Rock" approach. Basically you try different size rocks (weights) like ancient cheesemakers until you find what works for you. If you are happy  with the results, then you use that same rock (weight) all the time.

The other approach is more scientific and predictable using pounds per square inch (psi). Just search the forum and you will find several lively discussions.

[FarmerJd]

Welcome to the forum. Mark and Sailor gave you a great answer and I just thought I would add that I remember a time early on in my cheesemaking when it really puzzled me that recipes didn't explain the pressing very well. I think the reason is that people just did what worked as Sailor said without a scientific understanding but weren't really sure how to adjust for larger recipes. I actually called one of my cheese culture suppliers back then and she really didn't know. As you read through the threads trying to decide if your a "big rock" person or a PSI person, keep in mind that "big rock" people make great cheeses, and PSI people are right.
By the way, this site is the best place to learn. There are lots of very helpful and knowledgeable folks here. I hope you stick around and share your experiences. Good luck.

[Gina]

Mark and Sailor gave you a great answer and I just thought I would add that I remember a time early on in my cheesemaking when it really puzzled me that recipes didn't explain the pressing very well.

Thanks for the answers, guys. Very helpful. I've read several of the discussions here on the subject and since I havent used pi.r2 for years, I expect I'll be a 'big rock' person and settle for making great cheeses.   

It is good to know that in the beginning, much of the technique is using one's instincts as a jumping off point. It almost has to be that way since many of the recipes I've seen dont suggest mold sizes yet give specific times and weights for pressing.

[BigCheese]

On a similar note, does anyone have a psi chart for cheeses? That would be great. I suppose I have a brain of the "big rock" variety, yet something in me yearns for more. The only solution of course being to let the scientific people do the work and generously enlighten me.

[DeejayDebi]

Personally I'd rather use a big can of tomatoes than a rock! 

[MrsKK]

I have the Big Rock mentality, but use dumbbell weights.

Does that make me a Dumbbell?

[DeejayDebi]

I have the Big Rock mentality, but use dumbbell weights.

Does that make me a Dumbbell?

LOL My son took all the dumbbell weight when he moved out on his own years ago or I'd be using them too.

[padams]

I am definatly a "big rock" person....this tends to get a little to technical for me at times!  But, I sure love reading it all, even if some of it gives me a headache....

Debi, we dug all my DH free weights out of the garage....now they aren't collecting dust anymore 

But I still don't understand why increased density doesn't make a difference on weight and/or psi?

[DeejayDebi]

I am not sure what you mean by "increased density." Cheese density?

[padams]

yep, the density of the cheese ie; more curds in the same mould.

[DeejayDebi]

Because the surface area of the mold doesn't change just the thickness of the curds which will compress the same way under the same weight. The weight for the mold is based on square inches (the surface area) not cubic inches (the volume) of the cheese.

[padams]

Hmmm!  Just goes to show how much I know.  I am SOOO not a right-brained person!

In phoebeland, 2 + 2 equals 5 

[DeejayDebi]

2 + 2 has no value to me at all unless it has units. I am really bad at abstract numbers. Don't feel bad.