Jannie does it once again...
Its not easy to find a genius in South Africa, but, the former VodaCon and iBurps CEO is right on your street if you ever needed a genius. According to Jannie, milk no longer expires, as he clearly stated in this post (screencapped below for preservation as his friend will delete it from the forum as soon as this blog post is made known).
"Milk, petrol, etc. are all physical products and don't expire. Once you bought it, you take it home and consume it at your leasure.