Milk Today, to my horror, I found a tub, still sealed, of cottage cheese at the back of my fridge. On the  lid it said 'best used befor 13 May 2012'. I was prepared for the worst when I opened it - but to my surprise it looks, smells and tastes perfectly fresh. On other occasions I have noticed that milk and fresh cream seems still fresh long after its expiry date which in the case of milk is at least two weeks after the purchase. My question - what makes it possible that those products don't spoil, grow molds, etc. and keep fresh for such a long time, especially in the case of the cottage cheese which is over 4 months past its expiry date? G'Day to you too! The shelf-life of cottage cheese will be influenced by a number of factors including the type of cheese, how it was manufactured (e.g., exposure to heat) and how it is stored. It is possible that your fridge is actually colder than the recommended storage temperature (likely around 4oC), or colder at the back of the fridge, and that will have extended the cheese shelf-life. But I think the most likely reason for your cheese's longevity is the packaging. The cheese may have been well-protected from light and moisture. Also, I think it was scientists at Cornell Uni in the States that pioneered the use of CO2 (antibacterial) to improve the quality of dairy products, something that was picked up by