[whowhatwhenwherewhy]

I wonder if heating milk will reduce its calcium concentration, and also if it does, how much % would it decrease from let's say 20% to 70%.
On this website: https://www.news-medical.net/health/The-Effects-of-Heat-Treatment-on-Milk.aspx
It says that " reduced by 10-14% when it was boiled. It also found that the calcium content of pasteurized milk was reduced by 6-7% when boiled"
While from other sources that I read, they say that there is no effect because calcium is a "stable mineral element".

I did a complexometric titration of EDTA to try to test this, however there were issues with determining the endpoint, so the results were not accurate.

If heating milk does reduce its calcium concentration, then why?

[Hunter2]

It will be the opposit. If milk boils then water will evaporate, so the concentration will rise. The only thing what can be is as mentioned in the report, that Calcium gives some unsouloble precipitatiom, but this requires a Filtration after boiling.  Normaly the heated milk will be drunk, without further treatment.

[whowhatwhenwherewhy]

I've posted this on the High School Chemistry forum, but the answer I got seemed a bit dodgy, so I'm asking here.

I wonder if heating milk will reduce its calcium concentration, and also if it does, how much % would it decrease from let's say 20c to 70c.
On this website: https://www.news-medical.net/health/The-Effects-of-Heat-Treatment-on-Milk.aspx
It says that " reduced by 10-14% when it was boiled. It also found that the calcium content of pasteurized milk was reduced by 6-7% when boiled"
While from other sources that I read, they say that there is no effect because calcium is a "stable mineral element".

I did a complexometric titration of EDTA to try to test this, however there were issues with determining the endpoint, so the results were not accurate. However, it seemed like the calcium concentration did indeed reduce.

If heating milk does reduce its calcium concentration, then why?

[billnotgatez]

@whowhatwhenwherewhy

I have merged both of your posts on the same topic
We do not cross post in the forum for any reason per forum rules
Please read forum rules before posting

as for your question
hint   what happens to water when you heat a solution in an open container?
Does the calcium compounds in the milk evaporate before water?
How long are you heating the milk?

We are supposed to answer questions with hints per forum rules.

@Hunter2  I am not criticizing your answer please take no offense

[Borek]

Nothing dodgy about hunter's answer.

To add to what he wrote: there is a slight chance during boiling some of the calcium gets bonded to the denaturated milk albumins way too strong to be determined by EDTA, after all complexation by EDTA, which is a basis of the titration, is just an equilibrium process. Whether such calcium is still biologically available and freed during digestion - no idea. Most likely yes, but there are always exclusions.

[Corribus]

Probably you should distinguish analytical calcium concentration from calcium bioavailability. Most health websites would probably be concerned more with the latter, even if the language is left ambiguous, so make sure you don't confuse total concentration with bioavailable concentration by the way you frame your question or search for information.

[rjb]

As somebody who makes cheese in their spare time, this is something that I have looked into a little - I am however not an expert!

The general received wisdom in the cheesemaking community is that homogenization and pasteurization are processes that tend to reduce the ease and reliability of curd formation - something I have experienced and I think most people accept as being true. Greater reliability of curd formation can be achieved by adding calcium chloride into the milk and once again I think most people accept as being true. The most common explanation for this behaviour is that heat and homogenization reduce levels of calcium (and phosphate) in milk.

Logically however, the concentration of calcium cannot change unless either the volume of liquid is reduced (thereby increasing Ca concentration), Ca is somehow becoming magically able to jump out of our milk or our terms are somehow inaccurate. Of course the latter is our issue... Whilst overall levels of calcium (and phosphate) ions in our milk are unaffected by heat, the levels of soluble calcium and phosphate is...

Some very old data (1920s) that I came across showed that milk heated to around 100C (for 30 mins) can result in a 10% loss of soluble calcium. I would doubt that pasteurization would result in 6-7% loss of soluble calcium as cited, but perhaps combined with homogenization and a very old but not quite sour sample, you might get something in that order perhaps?

[Enthalpy]

Hi rjb, nice to see you here!

[rjb]

Hi Enthalpy,

I couldn't resist a question that relates (albeit obtusely) to cheese!

Keep up the great work...

R