An Energy Efficient Method of Making Mysost Whey Cheese

Have you ever eaten a popsicle and sucked all the sugar water out of the end, leaving only flavorless white ice behind?  Well, I used a similar technique recently in making a batch of Mysost, a whey cheese that tastes a lot like caramel.   Mysost is the name for Gjetost, which you are more likely to have heard of, that's been made from cow's milk whey instead of goat's milk whey.


Whey, after sitting outside in subzero temps



The concentrated lactose solution drained off the above frozen whey

 

When you think of Mysost, think of maple syrup production--a dilute sugar solution, maple sap, is boiled down to concentrate the sugars into a syrup.  Whey has about 4% lactose in it.  So when you boil it down, you concentrate the lactose sugar. I've often thought about making Mysost from the leftover whey since I have an abundant supply from my cheesemaking endeavors.  A couple years ago I was able to trade whey for pork with a local hog farmer, but since then I've just had to dump it into the compost pile.  I feel bad about it because whey has a lot of nutrients in it, but there's so much of it and it isn't nearly as tasty as milk to drink straight. 


I'd eaten and loved Gjetost before (if you eat it with apple it's like having a caramel apple) and wanted to make it from scratch, but knew that to make it you had to boil down whey until it was thick enough to set up like fudge.  Whew! That would take a lot of fuel.  One time Ziggy and April, who used to live here, tried to make some Mysost on their wood stove.  They said they were boiling whey for about 8 hours or so, and they ended up with a very small amount of Mysost.

Pure ice discarded from the separated whey concentrate

 

So knowing what I know about making apple jack and eating popsicles, and considering the below zero weather that's been nipping at our noses all winter long, I decided to take advantage of a few laws of physics to reduce the embodied energy of Mysost.  So I put the buckets of whey out in the below zero blustery weather and brought them inside periodically to skim off the ice.  The water is what's freezing in the bucket, while the sugar solution freezes at a lower temperature, so it separates from the ice when given the chance to.  I did this by tilting the bucket up with only a small opening for the sugar solution to drain off the ice.  With each succeeding freeze, I tested the brix and watched it rise.  12B to 20B and when the whey seemed to have the thickness of heavy cream, it was time to start the boiling process. 

 

Although it still took probably about an hour and a half to boil the rest of the way, the results were good.   The whey thickened up and I took the pot out to the frozen pond to flash cool it so the thick paste wouldn't crystallize, which it can do if it cools too slowly.  It did just what it was supposed to and after putting it in a mold I returned it to the cold outside to set the rest of the way. 

 

The only problem I had was that I think the whey had sat out a little too long at room temperature before I started freezing it and the resulting product was too acidic.  I'd concentrated the acids as well as the sugars.  This time, I'm not giving the whey a chance to go sour, so hopefully the finished product will be sweet and nothing else. 

UPDATE: The second batch of Mysost went faster and turned out sweeter because I didn't let the whey sit at room temp at all.  It seems to have turned out the perfect consistency and flavor.  With an hour and a half of boiling, some of which was just on my wood stove, I wound up with a little over 4 pounds of cheese from 10 gallons of whey. To call this stuff cheese seems a bit of a misnomer since it is more like cheese-flavored candy.