Thinly sliced apples are best for drying until crisp (especially the even thickness when using a mandolin), while thick slices will remain leathery and pliable. I wouldn't cut apples any more than 1/4-inch thick, especially if you want them crisp.

You don't say what temperature you used in the Excalibur. What were the manufacturers suggested temperature? You will find a lot of variation in temperature for drying apples among the "experts".

--115-degrees F will maintain enzymes in the apple slices - which is more in line with the raw foodists, but they won't be crisp. That's the suggested temperature from "Making & Using Dried Foods" by Phyllis Hobson.

--Start out at 150-degrees F. for 2-3 hours and then turning the temperature down to 130-degrees F until done to the degree of crispness you like. From: "How to Dry Food" by Deanna DeLong.

--In Mary Bell's book, 130-140-degrees F, and she gives this tip to crisp up a dried food - put it in the freezer (uncovered in a single layer) overnight. I've never tried that tip, so not sure how well it actually works.

--NESCO book suggests 135-degrees F for fruit.

--National Center for Home Food Preservation sites 140-degrees F.

The temperature needs to be high enough to draw the moisture from the food, but not so high it "cooks" it. A high temperature will cause the outside to get hard (case hardening) and the hard shell traps the moisture inside - which can lead to mold growth. You want food to dry from the inside out. Air flow is almost more important than temperature for proper inside-out drying.

The higher the sugar content a food contains, the longer it will take to dry.

Is the air entering your dehydrator high in humidity? The lower the relative humidity, the faster foods dry.

-Grainlady

Hi Grainlady - thanks for the quick reply!

I used a temperature of 135, which is what is recommended on my machine for fruits. The air is fairly humid - I'm in south Georgia and we are still in the 90s every day and very muggy.

I would like to slice them thin using a mandolin, but I can't figure out how to use one without hurting myself or wasting a lot of food. I have two with finger guards - one is Pampered Chef and seems very difficult to use. The second is just a standard one that has three removable blades (not adjustable), with a catch tray underneath. This one works fairly well, but the way the finger guard works, I waste probably 25-50% of the food if I just use the guard. This is because the tines are so long and guard doesn't work unless the food is pushed on to them fully.

I have used without the finger guard, but will not do that again. I sliced my thumb pretty good, and it really scared me.

So, I don't really know a good way to slice thinly without using just a plain knife, which takes forever! If anyone knows of a good mandolin that has a finger guard that is easy to use and won't waste a lot of food, please let me know!

Jennie

I wear a cut-resistant glove when using a mandolin, even when using the pusher, and would recommend one for anyone who uses a cutting mandolin.

Before getting an apple corer, peeler, slicer I would use one of those gadgets that pushes through the apple from the top to the bottom and cores and slices the apple into 8 wedges. I would use a paring knife to cut the wedges into 2-3 thin slices, so a little less work, but lots of waste. You can save peelings (if any) and cores and make apple jelly with them).

-Grainlady

I can't speak to the dehydrating (I'm here for the learning), but I do know slicers!

I have a very very expensive DeBuyer mandoline, with infinite settings, via crank, which was a present. Actually, it's a V-slicer, which helps prevent squishing. It has a huge pusher and a side handle, so if operated correctly there's no cutting of the fingers. The pusher has a stiff spring in it, so there's really very little that doesn't go through the blade. Probably a quarter inch on an apple with the skin on. It is fantastic for large scale processing. Better than FP, which is limited by the bowl size. Better than by hand, because of speed. If you're going to do a LOT of slicing, it's worth the investment.

I haven't used the latest models of OXO. They make reasonably priced real mandolines and their design is usually good. I can't speak to the guard, however. I haven't used any Zyliss, but they look well designed and are moderately priced. It might be worth going somewhere like Bed, Bath & Beyond and giving them a good looking over.

For smaller tasks, I use a Kyocera paddle mandoline. It has cutouts in the sides so that it can sit securely on a bowl, or you can just hold it over a cutting board or platter. It would be fine for slicing half a dozen apples, but could get tiresome for more. There is a size limit. The fruit has to fit between the side ridges. The pusher, however, is a flat, nylon thing, with nylon spikes. It doesn't attach to the fruit. You have to hold it with the pressure from your hand, but it works very well with no waste. I've never been cut, but, especially in a busy house where you can be startled, a cutproof glove would be a good idea. This one is inexpensive and very useful. And goes in the dishwasher, which is a boon (the OXO might as well--I don't remember).

Regarding apple slicers, the corer/wedger that Grainlady just mentioned is an excellent tool. If your apple is a little wonky, you can kind of wiggle and adjust, and I find it works better than an old fashioned corer, especially on larger apples. It is possible to slice through the edge of the core, however, so until you learn how to feel if it's askew, and even after if there's a wide spot in the core, which you may want to clean up from the wedges with a paring knife.

The quintessential apple corer, parer, slicer is a whizbang delight if you have an apple orchard and have to process bushel after bushel after bushel of apples. For the average homemaker, not so much. It takes an awful lot of flesh off with the peel (not such a big deal if you're making the apple jelly), and only works well on symmetrical apples. However, doesn't yours have an adjustment for the slicing knife? Maybe some don't. One of the advantages of these, with adjustable knife, is that it can slice really thin! Like an eighth of an inch.

I hope the dehydrating goes well. Keep looking, and you'll find a mandoline that suits you.

I have an OXO that's a little more than a year old and I never, never use it because of the stupid pusher, which is kind of like a juicer with spikes in the bottom of it. You need to push what you're slicing so far onto the spikes for them to hold it that you're lucky if you can slice a quarter of the item.

Besides which, it stores all the blades in the mandoline body itself, which sounds like a good idea but means a lot of disassembling and extra cleaning of sharp things not used every time I do use the darned thing.

It lives in a cupboard now and I rely on a sharp knife for what I can't do with the flat side of my julienne peeler. What a waste of money the OXO was.

Oh, dear! That sounds awful! Thanks, Writersblock. I've only used one, not owned, and didn't know all that.

Yeah, I have to admit that it cuts very well, nice sharp blades and a v-cut, but every time I read a blog post from someone who got a mandoline but doesn't use it because of being afraid of it, my guess is that it's an OXO, and it usually is.

Yep - another unhappy oxo owner. I hate the pusher thing! And the blades are sharp enough to make me wish it would work. Very occasionly I get it out and spent the whole time saying ' this is dumb dumb dumb.....'. Then wash and put away for another 6 months. I checked out a really nice one at Sur la Table years ago. Realized a cheap KA food processor cost the same and went with that. Love the FP but still want a mandolin.

I do have a apple peeler corer slicer that I use for dehydrating. And a nesco dehydrator. I usually dry for twice as long as you. I think crispness varies by variety, humidity, thickness and time. Also storage. Even if I get them crisp they will absorb enough water to get chewy if the container doesn't close tightly. Or is opened often.

Agmss15 - so you dehydrate your apples for about 48 hours?