ottawa foodies

I had a carton of soy milk in the fridge with only a little soy milk left in it. Before I left the house this morning I poured it into one of my Tupperware plastic cups, I put a lid on it, then put it in my lunch bag. I put my soy milk directly in the fridge when I arrived to work 15 minutes later. When I took my milk out of the fridge at lunch time there was a little bit of solidified soy milk floating in my cup. Since I am a germophobe and do not like anything floating in my milk I pitched it. The little chunk of whatever-it-was almost looked like tofu. Has this happened to any soy milk drinkers out there? Anyone know what it is/how it happened? I'm just curious to know what it is... I only had the carton open a week and a half and the expiry date is December 2013.

I love science experiments!
But I don't drink soy. Did the soy milk dry out or did it curdle? How did it smell? How long since you opened it up? Was the Tupperware contaminated? So many questions, no answers.
But I do think you have an interesting question.

It didn't look like the soy milk had curdled - that was actually the first thing I looked for-;) Dried out? Didn't look like it. It smelled just like soy milk but I didn't taste it to check for sour tastes, etc. Good question about the Tupperware - I usually clean out my cups with a dish mop similar to the one pictured on the right and it "looks like" I am cleaning out the liquids in there. But I can't get as much elbow grease with a dish mop than using a j-cloth and my hands. (Hopefully that makes sense?) I've heard of people making tofu skin but I believe that involves scalding the milk first but no heat was involved this time...

Forgot to mention I had opened the containter a week and a half ago.

On shelf-stable cartons, the expiry date refers to its life unopened. Once you open it, you should consume it within 7 days or so. Consuming beyond the expiry date is at your own risk - many things are totally fine I would bet. Others not.
I'd guess your beverage was borderline/near kaput and the transport time may have augmented that further.

When soy "milk" goes off it does become a bit chunky.
Also: your fridge at work may be too cold/is cold because it has few items in it.
Though homogenized, if it was the last of a carton it possibly had light sediment goodies making it slightly thicker to start with and a cold fridge added to that.
That brand of soy beverage has sunflower oil added which, as it's low in saturated fat, stays liquid in normal (~3C) fridge temperatures but in a 1C fridge may solidify more.

Experiment II: Try pouring some in the same type of container again and keep it beside the carton in your fridge at home and observe.

Token soymilk drinker here.
As AMR said, the bottom of a carton is always a little...chunkier? I'm not talking giant globs floating around, but I often see things the size of a grain of sand floating around in the bottom. Agitation and cold could probably get some of these to coagulate together.

Honestly, I never worried too much about it as long as it wasn't much bigger than sand and didn't smell off. I've never gotten sick off of "off" soymilk (oh, what a strange string of words) as I have with regular milk that was spoiled.

AMR and collisionofnova Thanks! I suspect it went off because I had the carton open for too long. I am always carefull about expiry dates and I usually drink the soymilk right away when I open it. The carton is usually polished off in three days - four days tops. The solidified stuff in the last glass I had last week sure looked interesting though-;)