If you’re using a half gallon canning jar to contain your milk, then get a medium sized bucket (about a three-gallon, or eleven-liter, capacity). The most important feature of the bucket is that it fit both the jar and your freezer, so I hesitate to give you a specific size.

Add about a gallon of water to a medium sized bucket.

To that water, add around 1/3 cup of salt and mix until the salt dissolves. This will form a brine which acts as an anti-freeze; you may need more or less salt depending on the hardness of your water.

If salt doesn’t work for you, try an alcohol solution starting at about half water, half isopropyl alcohol.

Keep this mixture in your freezer and every time you filter your milk, put it into a glass container like a canning jar, and submerge it to half way up in the semi-frozen brine solution.

Make sure the solution doesn’t come up over the top of your jar and into your milk. To be safe, you can cap the canning jar so that nothing falls into your clean milk.

When the milk is chilled, take it out and store it in the refrigerator.

Put your awesome bucket back in the freezer until you need it again.

Every now and then, switch out the solution to keep it strong.