The shelf-life of kvass is around 4-8 weeks from the moment you receive your order. Always remember that Quas can only be stored in the fridge. This is a relatively short shelf-life compared to other soft drinks or non-alcoholic beers. However, it ensures that whenever you decide to have a can of Quas, the good bacteria and yeast inside are alive and happy! Quas is still completely safe to drink even after the best-before date! We also found over a billion live bacteria present even 8 months after the best-before date. However, by that point, the majority of sugars will be converted into organic acids, which will make Quas appear more sour than you might like it.