Hi, I am pretty new to cheesemaking. I’ve been practising with powdered milk because I will be in remote locations on a sailing boat.
I made up a batch of full fat milk from powder with 1.5 times the normal mix of solids. I added calcium chloride to perk it up.
I added rennet at the normal strength for the recipe, and hey presto, the curd set beautifully in 30 minutes. I was so excited!
Then heated it to 43 degrees C, and it completely disintegrated. Can anyone tell me why did this happen? Any suggestions to stop it happening.
What cheese if any, could I make that don’t involve heating the curd?
Many thanks

Welcome Seamonster!  You brought back some memories.  I used to live in Micronesia, and would run into yachties all the time.  They were all great people, from all over the world.

I’ve never made cheese from powdered milk, so I’m just spitballing here.  First, the fact that you got curd would indicate you did something right.  I’m impressed that you found full fat powdered milk.  You might try adding a bit of extra cream, although that will likely not be available in remote locations.  I don’t know of any cheese that can be made without heating (cooking) the curd.  My first thought would be to go for soft cheese.

How quickly did you heat the curd?  It may be that heating too fast would ruin your curd.  Recipes are always careful to mention a slow heating process. 

What kind of water did you use?  Hopefully not chlorinated?

What was your process from curd set, through cut and on to cooking?  What did you stir with?  Spoon, ladle, hands?  And how gentle were you with the curd?

Did you start the stir and cook immediately after cutting the curd?  It could be that you need to let it rest for 5 to 15 minutes before disturbing it.

What kind of pot were you using?  It has to be non-reactive - i.e., no aluminum.  Best are either stainless steel or enamelware.

I’m sure I haven’t solved the problem here.  Just trying to raise some possible issues for consideration.  Let’s see if we can get this worked out.

Thanks for replying Rich. Hope to make it to Micronesia sometime myslf.
I’ll answer your points below:
Pot - stainless steel
Water to make milk: boiled and cooled tap , on the boat I’ll have access to pure water from the watermaker
I will be able to get UHT cream but I bet thats as badly damaged as UHT milk.
I added citric acid at the outset, as the recipe I was following called for that.
Once the curd set ( I was very surprised!)I cut into 3cm cubes I heated it very slowly (recipe did not state over what time). I didn’t let it rest first, but I certainly wasn’t in a hurry! Will do next time.
I swirled the pot rather than stirring the curds, as I was nervous of them breaking up - I saw this on a youtube video.
It all looked promising, though the curds weren’t really getting much firmer. The breaking up happened suddenly at 42 degrees and was total - like it went back to clumps of powder in whey. I thought I’d make ricotta with any disastrous curds but this mess wouldn’t have done that.
Jean Mansfields book states that ‘frozen and powdered milk have also been successfully used for cheesemaking, and while I don’t think you will win any awards using powdered milk, you will make edible cheese’. I’ve emailed her for any pointers, but so far no response!
I guess that not all powdered milks are created equal, so worth trying another brand, though back on the boat I won’t have much choice.
I’ll try another batch soon, perhaps with a starter to see if makes any difference.
I have 3 books here, all have quite different recipes for the same thing. Quite confusing for the novice.
I’m only really aspiring to make feta,halloumi, and mozzarella.
Thanks for your help. I’ll post my results back here.

Sounds like you were quite diligent.  Yes, I think a starter would make some difference.  It would allow the milk to acidify more prior to adding rennet.  You’d need to allow about 45 minutes for it to ripen properly.  Easy mozzarella recipes call for citric acid to accomplish the same thing.