IMHO, the 'best before' date is a 'guide'--and a reminder to stores to rotate their products. I found a sealed container of yoghurt that had migrated to the back of our fridge. It was about 3 weeks past the expiry date. I decided to open it--looked fine, just a little watery on top. Sniff test was negative for spoilage. Soooo I decided to taste it. It tasted fine and we used it that day. None of us got sick or dropped dead from salmonella.
I have frozen cottage cheese and ricotta that are at their 'use by' date, thawed and used in lasagna, with no ill effects. I have used canned goods that were a year past their 'use by' date. As long as the top of the can is not bulging out, and air whooshes
into the can when it is opened, all is good.
In the current litigious era, I feel that 'best before' and 'use by' are the food industry covering their collective behinds.