The artificial stuff doesn't need to be refrigerated either. Only the contaminated stuff goes "bad" and get a sewer smell. My experience is the real stuff gets darker over time but keeps its coyote smell. The artificial and watered down stuff usually doesn't change color much and tends to lose its coyote smell and the ammonia smell takes over. Some will add a pinch of skunk or artificial skunk to make it smell stronger.

Had a friend freeze urine from 3 different suppliers. That was a litte revealing also. I bet one supplier will start advertising his urine has antifreeze added from here on out despite the fact he promised is was straight urine previously.

If you want a quality urine, ask the seller to show you his set up.
If he can't or won't, he most likely is a middle man and doesn't have coyotes or do his own collecting.. . that you don't want if you can help it.
Bacteria from food and feces will cause spoilage.
Most people don't run a clean enough operation to suite my needs.
I always froze mine daily. Kept it frozen until needed.
Old ammonia urine will catch some animals.
It'll miss a few sharp ones too !
Coyotes don't respond to bottled up old urine, like the seller wants you to believe,
Night vision cameras have proven that. Still, if an animal walks up to smell it, most properly placed traps will catch them.

Old seasoned coyotes will often act quite differently to old bottled urine.
In the ADC biz, that's often the ones you gotta kill !

How many bait/lure/urine dealers collect their own urine?

Not very many.

if somebody is selling bobcat pee in pretty much unlimited amounts, dont buy ANY urine from them. bobcat pee is not available to purchase except in very very limited instances. i dont think anybody in north america is collecting even 20 gallons of it a year.

Meat fed house cat urine will work just as well.

No one wants to say that, but . . .

How come no one is penning up feral cats and feeding them muskrat ???