How long are egg-free dressings like Just Mayo okay to eat after sell by date? I recently ordered a jar of Just Mayo from an online store and was sent a bottle that has a sell by date for about a month ago. The obvious complaint aside, it got me wondering how likely it is that such a product would actually be unsuitable for consumption. I mean, products like Just Mayo or Vegenaise don't have any eggs or dairy in them (its kind of their selling point). So they wouldn't 'turn' nearly as quickly as traditional mayonnaise, right?

My question is, how long would it take for an egg-free mayo to actually go bad? I've seen similar questions here about condiments and sell by dates, but whenever it comes to mayo, the eggs always come up as a key factor and that's not an issue with the products I'm talking about. 

Here are the ingredients of Just Mayo:
I couldn't find a previous answer specific to sell by dates and condiments.  Most condiments, mayo with egg included, are made safe by creating an inhospitable environment for bacterial growth.  The addition of acids (i.e, vinegar, lemon) or other "preservatives" accomplishes this.  Sell by dates are usually an indicator of quality, not safety.  Items such as this are safe for a very long time after the expatriation, especially if unopened, though the quality (taste and consistency) degrades. Once opened, you have the opportunity to introduce bacteria and spores to the contents.  Again, bacterial growth will be inhibited by the product itself.  The most likely problem would be mold growth.  If this occurs, discard.