Here's a quick tip. You go to cook something or have a bowl of cereal, need milk. You grab the milk and it's expired, stinking to high heaven! It only last a week!
But If you had bought Heavy Whipping Cream, it last fresh two months or more! Need milk? 1 part heavy Whipping Cream to 3 parts water. Adjust as you like. Need butter? Pour it in a bowl, put it under a mixer and when the mixer starts jumping up and down on the counter, it's butter. Pick out the butter and squeeze it out. Salt it if you like. Were not done! Cover the squeezing's and let sit on the counter for a few days. Butter milk! Or you can cook with the squeezing's or use it fresh as sweet milk. Of course you can whip it to top pies. Next time you go to the store, look at the expiration date on the heavy Whipping Cream!