Guacamole - Why am I still alive?
Almost a month ago I posted this thread:
I put the stuff away in the fridge - tightly closed container but certainly not hermetic.
I was going thru the fridge yesterday and spotted it - I opened and sniffed etc. - all looked and smelled OK - I took a small taste - OK - even the bitterness seemed to have diminished significantly.
I then ate a significant amount with tortilla chips - and am here today to tell about it.
I'm with jounipesonen, this is exactly the kind of thing I do when I find a container lingering in the back of the fridge - open, look, sniff, and cautiously sample. Why throw something out if it's fine to eat? I agree that folks with compromised immune systems or sensitive guts may need to be more cautious. But so far, I haven't suffered noticeable ill effects, so so far, so good.
As to the OP's question, stuff going bad is a complex equation, not easily boiled down to a simple "use by" or "sell by" date that some folks like to believe is some type of a magic cutoff. If your guac was put in a container soon after making, well sealed, and kept in the lower back section of the fridge (the coldest), and the container not opened, used, and closed repeatedly, that would last much longer than something kept open on the counter for an hour before being put away, kept in the front of the fridge, and opened repeatedly.
It's a matter of giving bacteria an opportunity to colonize, and then to grow. If your goods are put in a container soon after making, and kept cold and sealed, they'll last much much longer than the same good opened to the environment (opportunity to colonize) and kept warmer - even if in the fridge (opportunity to grow).
Personally, I find "use by" dates pretty much useless, and ignore them on a regular basis, because the longevity of a product has more to do with how you handle it than it's age.
Looks like the acidic ingredients did a good job of holding off the bacterial growth. But I'd still say you're lucky not to have suffered the ill effects of some food borne illness and would not recommend keeping guacamole that long, refrigerated or not.
The salt and the acid (lime juice, usually) in guacamole slow down the rate of spoilage and limits the potential for food poisoning (which is not the same thing as spoilage). Refrigeration helps as does keeping the container closed. All that said, I wouldn't recommend making this kind of thing a habit. Trying something once and getting away with it does not make that practice safe.
BTW - not trying to scare you, but... many forms of food poisoning have an incubation period longer than a single day. Many can take several days for symptoms to show up. Some can take over a week.