Whenever you find a sale on REAL butter, go ahead and stock up. You can freeze butter or you can home-can it. Canned butter lasts for years if the seals are secure and it's kept in a cool place. Always pressure can butter instead of water-bathing it. Butter is dairy and non-acidic so the water bath method will not stop botulism. Canning butter is so easy and the best type of jars to use are half-pint, wide-mouth jars. The wide mouth makes it easier to get the butter out of the jars and opening a half pint at a time is convenient for most families.