So I bought the ingredients for a terribly unhealthy microwave burrito enchilada-style casserole recipe today. The recipe, of course, called for enchilada sauce. So I went out and bought Las Palmas brand mild enchilada sauce along with the other ingredients. When I popped open the sauce, the kitchen was immediately filled with the pungent smell of dog food. Having no idea what the sauce was supposed to smell like, I put it in anyway, thinking the smell would go away.  After an hour in the oven, the smell was still there, and the heat made it stronger than ever. And when I tasted it, the sauce tasted of dog food. I've checked the can (the expiration date wasn't for another two years) and scoured the Internet, but I can't figure out any reason the enchilada sauce would take on this particular smell and taste.   Could anyone help me figure out why? It won't improve the casserole, but it will assure that I'm not insane for having this apparently unique experience. 
EDIT: Although the question title says "fruit pies," the question specifies a "fruit custard pie."  The following answer relates to custard pies and other pies containing fillings with eggs and/or milk.  Actual plain "fruit pies" generally contain enough sugar to prevent rapid spoilage and therefore often do not require refrigeration.  If you do plan to refrigerate a plain fruit pie, there's no significant advantage to getting it into the fridge quickly.    Pies do not have to come down to room temperature before refrigeration.  In fact, most food safety organizations recommend the same general policy for egg-based and dairy-based pies as they do for other foods: don't leave leftovers out for more than 2 hours after cooking.  See, for example, recommendations here:     Foods which contain eggs and milk, with high moisture content, must be   kept refrigerated, as bacteria love to grow in these foods. Failing to   put that pie back into the refrigerator before it has remained on the   counter for more than 2 hours can make a very merry celebration for   the bacteria, but not so good for friends and family.   So, 2 hours should be a maximum before refrigeration.  As for recommendations about the appropriate time to let cool at room temperature, see here, for example, which states:     Cool cream pies at room temperature for only  30 minutes after you   take them out  of the oven.      After 30 minutes, put them in the refrigerator  to complete the   cooling and to keep them  cold.   While it says "cream pies" here, the guidelines above in that link imply that such guidelines also relate to custard and pumpkin pies.  (The first link above also says the same thing about pumpkin pies.)  Basically, the only reason to keep a dairy-based or egg-based pie out of the refrigerator after removing from the oven is to allow cooking and setting to continue.  Many custard pies will continue to set a bit while cooling, and putting them in the refrigerator immediately might "shock" them and disrupt this process of solidification.  Changes in humidity levels and condensation might also have unpredictable effects on the pie surface while it is very hot.  (As for concerns about putting hot food in the fridge, see links to food safety organizations on the subject in my answer here.  Basically, you shouldn't put a hot or warm pie near anything that's very perishable in the fridge.  Otherwise, you're safer getting it in the fridge as soon as it has stablized after cooking, which shouldn't take more than 30 minutes or so.) 