I buy a two to three weeks supply at each visit to the dairy and freeze the excess but there is a slight deterioration in quality upon thawing. It is still better than the pasteurized milk. I like your idea of using pre cooled and sealed glass jars to extend the shelf life and am going to try it. I remember years ago when my mother allowed the milk to clabber and used it for cooking, especially for baking. My older brother liked to eat the clabber but I wasn't as adventurous as him.