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GENERAL CHEESE MAKING BOARDS (Specific Cheese Making in Boards above) => EQUIPMENT - Making Cheese => Topic started by: meyerandray on May 03, 2013, 12:30:04 PM

Title: Anyone use a copper cauldron to make their cheese?
Post by: meyerandray on May 03, 2013, 12:30:04 PM
I am looking to upgrade from my 8 liter pasta pot, and have found lots of copper cauldrons, which are traditional for making toma (tomme) and other alpine cheeses.  I was wondering if anyone has any insight or advice to give me before buying one of these.  This is an example of one I am looking at.

http://www.subito.it/arredamento-casalinghi/pentolone-rame-grande-torino-62116307.htm (http://www.subito.it/arredamento-casalinghi/pentolone-rame-grande-torino-62116307.htm)

 I am wondering if there is anything I should do to restore it?  It doesn't look coated inside, (alluminum or whatever they coat copper with these days), would I need to have that done in order for it to be hygenic and safe healthwise?
Any thoughts, ideas and comments are welcome.
Thanks, Celine
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: WovenMeadows on May 03, 2013, 05:18:06 PM
Coating or lining the copper would defeat the purpose, I think - as I understand it, it is the reaction of the copper with the (acidic) milk and whey during the cheese making that gives the alpine cheeses some of their character.
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: linuxboy on May 03, 2013, 07:08:11 PM
Quote
it is the reaction of the copper with the (acidic) milk and whey during the cheese making that gives the alpine cheeses some of their character.
Curious, do you remember the source for this? Because beyond thermal conductivity properties, I have found copper to make no difference.
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: meyerandray on May 03, 2013, 07:39:54 PM
I too have heard that copper helps in the acidification of the milk.  I am looking at buying this because it doesn't cost much, and seems pretty perfect.  I was concerned because I thought (sometimes I dream wild stuff up that never actually happened, so I could be wrong) that there was some finding that non-coated copper could be hazardous to our health, maybe carcinogenic or something?  I also wanted to know in general if anyone had any experience using copper for cheesemaking.  Does it tend to scald on the bottom?  Is it harder to clean?  I have heard very different maintenance suggestions from different sources (none of which actually USE a copper pot) which vary in treating it with vinegar and rock salt to never leaving it without water in the bottom.  I wasn't convinced by either one of these ideas, and won't be until someone with actual experience tells me what they have found works/doesn't work.
Linuxboy, do you use copper in cheesemaking, or were you referring to cooking?
WovenMeadows, I know that that is yet another advantage to copper in cheesemaking, but nowadays they coat the inside of all copper pots and pans intended for food use, I thought that was for health reasons? 
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: linuxboy on May 03, 2013, 07:55:21 PM
Quote
Linuxboy, do you use copper in cheesemaking, or were you referring to cooking?
I have done both. Beyond thermal properties, I have not found it to make a big difference. That said, rapid heating and rapid whey loss for alpines and parmigiano reggiano is am important part of the process. But that's physics or at best physical chemistry, not chemistry. Copper has a patina after extended use. I just don't see how it makes a chemical difference.

Quote
I too have heard that copper helps in the acidification of the milk.
How do you think it does that? What does it do specifically? I think it's a myth... smokes and mirrors for marketing purposes; all the data from trials I have shows absolutely no difference in pH.
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: meyerandray on May 03, 2013, 08:43:45 PM
I just quickly googled the effects of copper in cheese production, and got this article.  I will do some more in depth research and get back to you, but I think I won't be buying copper for my home cheesemaking...
http://www.izsler.it/izs_bs/ftp/doc/CREF%20latte/pubblicazioni/cessione%20rame.pdf (http://www.izsler.it/izs_bs/ftp/doc/CREF%20latte/pubblicazioni/cessione%20rame.pdf)
I here is a translation of the "introduction" section, which pretty much summarizes what copper's chemical (in very basic terms) effects are on the cheese:

INTRODUZIONE – La presenza di tracce di metalli in prodotti lattiero caseari assume particolare
importanza poiché per diversi elementi è stata dimostrata una elevata biodisponibilità per l’uomo se presenti
in tale categoria di prodotti [1]. Per quanto riguarda i due più importanti formaggi D.O.P. nazionali
preoccupazioni sono destate dalla lavorazione caldaie di rame, metallo essenziale, ma ad alte concentrazioni
potenzialmente tossico. Anche le ricadute tecnologiche dovute alla presenza di rame sono rilevanti. Il
metallo, infatti, può modificare il metabolismo di diversi ceppi batterici [2] potendo favorire la crescita di
alcuni ceppi a scapito di altri. Concentrazioni di rame a livelli particolarmente elevati possono anche indurre
modificazioni delle caratteristiche organolettiche del prodotto finito, fino a produrre un inverdimento del
prodotto [3; 4]. Il rame può, inoltre, promuovere fenomeni di ossidazione delle frazioni lipidiche del
formaggio con produzione di molecole dall’odore sgradevole, oltre ad ossidazione del colesterolo con
formazione di ossidi promotori del processo di aterosclerosi [5]

INTRO:  The presence of trace metals in dairy products become of great importance as various examples of these elements have demonstrated a high bioavailability to humans when present in this category of products (dairy).  As far as the two most important national DOP(Denomination of protected origin) cheeses go, worries have arisen in regards to the use of copper cauldrons in the production process, as it is an essential metal, but at high concenctrations is potentially toxic.  Even the technological effects as a result of the presence of copper are relevant.  The metal, in fact, can modify the metabolism of various bacterial strains, with the ability to favor the growth/development of certain strains, at the expense of others.  Particularly high copper concentrations can actually cause a modification to the organoleptic qualities of the finished product, or can even cause the product to turn green.  Copper can also promote oxidation of the lipids present in the cheese, resulting in the production of foul smelling molecules, in addition to the oxidation of cholestorol with the formation of oxides which promote the process of atherosclerosis.

I am no translator, so I hope you can get the gist. 

My scientifically ignorant conclusion is that copper leeches into the milk, and thus changes the environmental qualities in which we process the milk, so it would in fact result in a change in the acidifying process.  This is based of of one quick article that I found in 5 minutes though.  I am sure there is tons of info on the subject out there.
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: linuxboy on May 03, 2013, 09:28:10 PM
Right, so I read Italian pretty fluently, I got their point. And it is absolutely true that bioavailability increases. And it's also absolutely true that copper levels increase cell and strain growth, to a point. However:

1) Milk has generally a good level of copper already, unless animals or pasture are poorly managed. and
2) Human bioavailability has little to do with cell growth rate or acid production rates
3) Copper toxicity is a primary way I see that metabolism is affected due to suppression. With normal care, there is not enough leeching to cause cell toxicity to LAB bacteria.

I didn't mean to make this a big deal; I've just never seen really convincing data, and hoping someone else had.
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: meyerandray on May 04, 2013, 12:53:52 PM
No no, definitely not a big deal  O0 I knew absolutely nothing on the subject, like not enough to even know what questions/curiosities to have. You sound like you have a pretty good scientific/microbiological foundation. That is very cool that you read Italian! What did you think of my translation? I am fluent in both languages, but struggle with translation, I would love to be better.
So, back to the copper, seeing as no one else is chiming in with concrete or specific info contrary to what you know, and you have at least convinced me that you know what you are talking about, what would you advise me? Buy the copper cauldron or not? If I do, would I be limited to specific cheeses, or could I also use it to make, for example, a camembert or a gorgonzola or a Crottin? Would leeching increase in a slow acidification like Crottin? You wrote that with normal care one could contain leeching, what would normal care be? Would my life be simpler if I just spring for a large stainless steel pot?
Thank you! Celine
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: linuxboy on May 06, 2013, 12:10:40 AM
Quote
What did you think of my translation?

I thought it was excellent, especially for technical content.

Quote
Buy the copper cauldron or not?
For hard cheese (tomme, grana types), yes. For long lactic or semi-lactic style, I would go with plastic or stainless.

Quote
for example, a camembert or a gorgonzola or a Crottin?
For those cheeses, the copper provides no advantage over other materials, bu would work fine. The reason copper works is that it heats really well, and evenly. And which crottin style?

Quote
Would leeching increase in a slow acidification like Crottin?
Exactly, more acid, more contact time = more leeching. I don't have good numbers for you for how much is leached. I have no idea, never seen any good studies. I've seen some numbers for cooking food, but nothing for cheesemaking.

Quote
You wrote that with normal care one could contain leeching, what would normal care be? Would my life be simpler if I just spring for a large stainless steel pot?
IMHO, yes, it would be simpler. Normal care means not letting anything burn. Not cleaning with abrasive chemicals (vinegar and salt are fine). Basically, using to develop a patina to condition the copper, which helps prevent leaching. And then maintaining the patina and not destroying it. Do you know how parmigiano reggiano copper vats have this great, slightly dull color? that's patina from use. Not shiny, but with a thin oxidized layer.
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: jwalker on May 06, 2013, 12:42:47 PM
There have been many studies done on the effects of copper vats on the final cheese product , it seems that thermophyllic starters are the most sensitive to copper and those cheeses made with them are the most influenced by the copper.
In Finland they make emmental in stainless vats , then actually add copper salts to it , to make it more like the original.

"In Finland, where
stainless-steel vats are used for Emmental manufacture,
extra copper is added as CuSO4
salt solution into the
cheese milk to increase the copper concentration of the
milk from less than 0Æ1 to 1Æ3 ppm. This supplement
brings the copper level in Finnish Emmental cheese close
to the traditional Swiss-make Emmental cheese, but is still less than 15 ppm, which is the highest acceptable copper level."



The study was conducted to evaluate the influence of copper vat on cheesemaking technology, ripening and texture of Parmigiano Reggiano cheese. Eight comparative cheesemaking trials were performed using four copper vats and four steel vats. Results revealed that the cheesemaking process was modified using steel vats during the final step of cooking because it was not possible to reach the same thermal increase observed with copper vats. Proteolysis was different in 17 month aged-cheese cooked in steel and copper vats. Cheeses cooked in copper vats was characterized by higher ripening index (pH 4.6 soluble nitrogen ×100/total nitrogen), free amino acids content and ratio between breakdown of peptides and native casein fractions. A higher proteolysis of α2-casein, α1-casein and β-casein were observed in cheeses produced in copper than steel vat. Free amino acids (FAA) profile of all 17 month-aged cheese produced in copper vat agreed with standard requirements for typical ParmigianoReggiano cheese. The FAA profile of all cheeses produced in steel vat did not meet the standard requirements. Cheeses produced in copper vat showed better structural and sensorial characteristics better than cheeses produced in steel vats.

http://www.cabdirect.org/abstracts/20093229198.html (http://www.cabdirect.org/abstracts/20093229198.html)

Cheers , Jim. ;D
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: linuxboy on May 06, 2013, 02:25:16 PM
Quote
it seems that thermophyllic starters are the most sensitive to copper and those cheeses made with them are the most influenced by the copper.
Influenced in terms of growth rate? Yes, true, if milk somehow is copper deficient, a vat will help a tiny bit. Not enough to make a difference, not statistically significant.
Quote
extra copper is added as CuSO4
salt solution into the
cheese milk to increase the copper concentration of the
milk
CuSO4 is absolutely not the same thing as a lovely, chelated, complex form of copper available in milk. It has hugely different lethality and bioavailability rates for individual cells and for organisms. I don't buy it. The conclusions of that same study you cited agree with me: here were not signifficative differences in the microbial counts at the
different sampling points when comparing cheeses where Cu was added or not to milk during
manufacturing. The pH and solid content were also not showing significative differences.
Cheeses without Cu addition shown more lactic acid consumption and propionic acid
production after 30 days ripening period compared with those where Cu was added. Only a
tinny difference can be seen in the proteolysis after 60 days ripening between the two set of
cheeses


However, copper does help inhibit Clostridium, which I completely agree with, and this is also supported by the findings in the study. Good milk shouldn't have spores in it, anyway.

Quote
The study was conducted to evaluate the influence of copper vat on cheesemaking technology..... it was not possible to reach the same thermal increase observed with copper vats.
Completely agree, the thermal properties make a difference. However, I can design you a vat out of stainless with similar thermal transference and heat dynamics. This is still physics, not chemistry. I can completely see how heat rate makes a huge difference, and this is supported by the study.
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: Back 2 The Frotture on May 07, 2013, 09:15:02 PM
Practical point; Using copper pots regularly the advantage I can see is that when you stop heating and the heat does not dissipate as fast as with stainless steel.  One disadvantage is that if left in a humid environment a patina will form if not used regularly.  90€ sounds like a steal for a 50 liter pot
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: meyerandray on May 08, 2013, 10:08:51 AM
I have decided not to get it for now.  They don't cost much here, I live in a region where they were used traditionally for large polenta batches, so you can find them for €50 too, and pretty regularly.  For the amount of hard cheese that I make, I think this would be a premature buy.  I have been trying to perfect my freshi-ish goat cheeses (robiola and crottin de chavignol) lately, and I don't think this copper pot would be good for that because:
-I leave it to acidify up to 24 hours, and would thus need a top for the pot which could be a pain to find, and potentially expensive, plus the extra exposure could lead to more leeching
-The fresh cheeses have to be eaten within a month, and 50 liters may be too much for us to use/give away
- Although leeching can be contained and they use copper in many DOP/DOC/DOCG cheeses, I don't fully understand the nutritional advantages/risks of copper and how to walk that fine line.  I am worried that I won't take good care of it or will make some ignorant mistake and either ruin the pot or leech too much copper into the cheese, and I feed my cheese to my son, and I eat it and am pregnant, so I don't want to risk right now. 
I am happy to read your discussions on the subject, and once I have understood a little more, I may consider getting one.
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: Alpkäserei on May 16, 2013, 10:03:17 PM
I use copper. Let me give a little information on how I learned.

i don't know so much the science or biochemistry, etc. But I know tradition.

If you don't know of me, I learned cheesemaking in Switzerland and have made it a point to increase the knowledge in the US of Swiss traditions. I am of Swiss cultural heritage, from a family that maintains very close ties to the Vaterland.

In Switzerland, cheese is ALWAYS made in a copper vat. Yes, it has a huge impact on heat exchange rates, etc. But tradition holds that the copper has a distinct affect on the flavor of the final cheese. Swiss cheesemakers will tell you there is a depth to these cheeses that is impossible to attain from stainless steel. I can't site any studies, etc.

As for safety, I can assure you it is safe. ignore any fearmongering, etc by some modern research. It's not true, and we have thousands of years of proof. Copper is dangerous to cheese only if it is not properly maintained. LB says it develops a patina with use, this is precisely what we do not want. We are taught to clean the copper daily so that it is always bright. The patina is an oxide of copper, and it can react with certain chemicals in the milk -in particular sulfur compounds- and form a variety of poisons.

People like to look at scientific research and see all the potential dangers. nevermind the fact that we've made copper in cheese for millenia.

As for whether or not it has a positive effect, I am certain that it does. This may have more to do with the thermal properties than anything else, I do not know. But this I do know, I can always tell by the flavor whether an emmentaler was made in copper. The steel vat cheese always seem to lack something.

In a lot of our Swiss style cheeses, timing of the heating is very important. The fact that we can take the heat from the vat and count on the copper to immediately stop putting heat into the cheese is a major factor.
I'll never use steel if the government doesn't make me.
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: Alpkäserei on May 16, 2013, 11:45:40 PM
regarding cleaning I should say some to.

First opinion differ from region to region. I just saw where LB talked about the patina on Parm vats, in the Berner Oberland that would be considered terrible. The two cheeses are made almost exactly the same. So maybe it's an example of the Swiss obsession with cleanliness, I don't know. I do know that Bernese cheesemakers (and many Swiss cheesemakers) actually have a rather low opinion of parm makers. Maybe just some ethnocentrism showing through  ;)

But we make the cheese each day, and wash immediately afterward. To wash, all we do is remove the whey, put in some hot water and scrub with an abrasive cloth. For example one of these green scotch pads made by 3M. The water is removed and fresh put in, and scrubbed more. This is done until the water no longer gets dark from the cleaning. Then it is very important that all water be removed and dried off with a clean towel. If it's left in the vat, it will cause spots of patina.

If the vat has sat around for some time and needs cleaned extensively, I will mix together salt and vinegar and then heat them together.  Then I will scrub with this. This will strip the copper down. Then I rinse all of this out, and proceed to wash like normal. It's important to wash off with water after vinegar, as the stripped copper will patina very fast if not cleaned right away.

Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: meyerandray on May 17, 2013, 09:38:19 AM
Thank you alpkaserei, I have been wavering back and forth on whether or not to get this cauldron. I still don't know if i will make enough Alps style cheeses to be able to maintain it well, but i do believe in the organoleptic contributions of copper to the cheese, and now that I know how to care for it, i am considering once again...
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: smolt1 on May 17, 2013, 01:49:18 PM
Before about 1913 no cheese was made in stainless pots because it wasn't "invented" yet.
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: linuxboy on May 17, 2013, 07:21:20 PM
Quote
If it's left in the vat, it will cause spots of patina.
Every single copper vat I've ever seen in any region has a microlayer of a thin oxide. It forms naturally upon exposure to air, and very quickly. Your process is very similar to the parmigiano makers. The key for them is:

1) Never let milk or whey bits stick to the copper and dry off. They constantly splash whey all over the vat to keep it wet
2) Get rid of all solids/matter (eg whey) as soon as possible and rinse right away
3) use gentle acid washes and a mild scrubber, using vinegar wash or vinegar/salt when necessary

So their maintenance schedule it about the same. A water-based patina (the dark, uneven spots) from not drying or not washing or not keeping clean is undesirable. But raw, dry copper oxidizes almost immediately upon exposure to air, and this helps prevent further leaching. Else, your copper would be ultra, ultra shiny. When you wash, after it dries off and sits for an hour, does your vat dull a little? Just not quite so shiny? That's the patina I meant. Not like verdigris or anything like that.
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: Alpkäserei on May 17, 2013, 08:19:20 PM
you are right i misunderstood your explanation
i understood you to be saying they left their copper to develop the dull brown color
but with our water based cleaning there is another situation, since our goal is to remove all traces of any acidic substance we rinse thoroughly with water. i purities in the water such as iron, calcium, etc. actually form a thin protective film. our aim is to maintain a copper surface, as bright as we can manage.
but yes, it will dull slightly. but if it becomes brown like a penny, that is considered bad.
as for stainless steel, yes about 1912 a local fellow developped it. Elwood Haynes , whose company still is in business in the nearby city of Kokomo.
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: Alpkäserei on May 17, 2013, 08:47:42 PM
this is also why we wash with water whenever we use vinegar. vinegar leaves the copper raw and unprotected.
such will patina and dull immediately. so we wash with water which leaves a film on the surface, significantly slowing the patina. this of course is a thin, weak protection that will not last long. but it is sufficient to stave off oxidation for a few days, in our environment.
but thats how i learned. lb has presented the possibility that a little dullness might not be so bad. if it works in Parma, perhaps it could work here also?
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: linuxboy on May 17, 2013, 09:28:31 PM
It's a really thin, tiny layer. What it does is help to prevent excess copper leaching. Perfectly harmless and desirable. If you were to soak in a concentrated vinegar or other acid, the copper would pit... or would otherwise get worn down to the raw metal. And when it does that, instead of copper oxide, the thin layer has various copper salts that are not as good at maintaining the integrity of the copper. That's what I meant by no harsh treatments with chemicals. Maybe as a one-time reconditioning process going more harsh is fine, but generally, a light acidic scrub and it's good to go.

With harsher chemicals, pitting is also a concern. One of the beautiful aspects of your approach with the 3M pads is that they are ever so slightly abrasive. And if you are really thorough in the cleaning, going in a repeat pattern, in the same direction with the pads, it puts an excellent finish on the copper and has this "sanding" effect. Helps to keep a smooth surface, which prevents biofilm from forming and removes pits and hidey holes that bacteria live in.
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: Alpkäserei on May 18, 2013, 02:32:47 AM
And if you are really thorough in the cleaning, going in a repeat pattern, in the same direction with the pads...

You mean like washing the entire vat 4 times?  ;)

I was taught to use a circular scrubbing motion, going around in a pattern, and do this over the entire vat with every change of water. Yes, the idea was to polish the copper. (not make it Polish. sorry, bad pun)

I don't know HOW they did it before the 3M pads...
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: Spellogue on May 20, 2013, 05:48:57 AM
Very interesting thread.  I would love to have a large copper kettle. I started looking for one for homebrewing years ago, but they're so expensive new and I've yet to find a decent used one here in the Midwest US. 

A marginal anecdotal (hardly scientific) note I might make is my experience with using copper as a mordant for natural dyeing.  A mordant is a metal salt used to chemically bond natural dyestuffs to fiber, e.g. wool.   Alum (aluminum potasium sulfate) is rather common, provides for neutral color effect and is the safest metal mordant used in the sense that its application is relatively non-toxic. Iron (ferrous sulfate) saddens or darkens colors  and Vitrol (copper sulfate) brings out green hues. These two are also common mordants but are certainly not body friendly in large doses. Tin (stannous chloride) makes for bright colors, but is highly toxic.   Chrome (potassium dichromate), produces beautiful rich orangey tones but is rather deadly if even small amounts enter the body.  All these mordants are safe once heat bonded into finished yarn, but utmost care must be taken in the process and with concern to disposal of the byproducts.

The metal salts are usually used in small amounts in crystal form for the most control as mordants, but historically the effects of iron and copper could be had by using cast iron and copper pots in which to simmer the wool.  Certainly even a chip in an enamel pot has leached enough ferrous oxide into a dyebath to have a saddening effect on the fiber I've dyed (not always a bad thing).  Likewise I've added pieces of copper pipe to a dyebath to successfully produce a greening effect to the resulting colors.  Temperatures at or just below boiling are used in natural dying.   Whereas most cheesemaking temperature are nowhere near that high I'm not surprised to read here that at least subtle effects are produced by the use of copper pots in the make. 

I'm curious to know how the taste (or other) differences might be described between cheeses made using copper vs. non-reactive pots.  What about other metals?  I've used only stainless steel and anodized aluminum (Calphalon) and haven't noticed a difference.  I've been tempted to use an old 4 gallon aluminum stock pot we have for a larger make, but I'm concerned that might be unwise.



Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: Back 2 The Frotture on May 29, 2013, 08:05:26 PM
Thanks for the useful info. So to go out on a limb... if a copper pot is cleaned but not properly dried, forms a patina, and is used the next make, could this alter the whey's color?
Title: Re: Anyone use a copper cauldron to make their cheese?
Post by: linuxboy on May 30, 2013, 03:53:17 AM
Possibly. How cleaned/sanitized before use?