Keeping uneaten canned food from drying out

My cat prefers canned food, the moister the better.  Friskies Pate is usually acceptable, and usually anything Fancy Feast.  I've been trying other brands, but that's for another question.  

I put out maybe 1/4 or 1/3 of a 5.5oz can in the morning.  Quite often she eats only some of the food, then heads off for a few hours of important cat business such as napping, then eats more of the pate later, if it's still moist.  She won't touch it if it has dried out.  I tried mixing water into some of the breakfast remains before it dried out, but that didn't make it any more appealing later.  

I prefer not to be tossing out 1/2 of all the canned food I buy.  Any advice on how to keep pate appealing?  Or chunks in gravy?

I use the lids off of the frito's dips to put on the cans. It fits perfectly on a 5 ounce can. You are supposed to refrigerate any portion that is not ate in a 20-30 minute period but my cats wont eat it if it has. These help it from drying out. I buy the dip often for my kids so I always have them on hand.  

There is a bowl that seals tight and promises to keep food fresh, I don't own one so I can't vouch for it but it looks good: http://www.luckypuppymag.com/keep-cats-food-fresh-bowl-seals/

Often I'll pick up the small foam plate I put food on and slip it into a baggie. I bought some  plastic lids at Walmart in the pet food section that fits those cans too. The baggies work well to just slip the can inside too, and then put it into the fridge.  You can warm it slightly in the microwave to make it more appealing, just make SURE it's not too hot!

All good tips but may not work if the OP puts food down and then goes out for the rest of the day. Try freezing food into portin sizes and put the frozen chunks into a programmable timed feeder. The food will slowly deforst over the next few hours and stay moist longer. The lid of the feeder will keep the food from drying out, too. Some feeders have an ice pack feature to keep food cool which may also preent drying out too fast. I like the Petsafe 5 c ompartment feeder. It doesn't actually have an ice pack but there is a small slot in the base of the feeder which will fit a mini lunch box-type ice pack.

If you are home, you can try soaking some freeze dried meat treats (whole or crumbled up) in water for a good 10 miutes or so and then pouring it over the dried canned food to re-moisten it and make it more appealing. The water will soak up the freeze dried meat flavor and become a sort of broth.