Dehydrator math: Pineapples

For today’s issue of dehydrating math, I did not count the weight of the core, skin or green leafy top. At least where I live, pineapples are not sold by weight but rather priced per unit. I paid 4$ Canadian for this one.

pinapple fresh

Like before, I weighed the pineapple before and after dehydrating.

pineapple with water

I accidentally set the scale to pounds, but it’s easy enough to convert to grams, 787 of them.

The pineapple filled up my entire 4-tray dehydrator to 100% capacity exactly.

pineapple dehydrated no waterDried out, the pineapple is shockingly light – 123 grams, a tiny 15% of initial fruit weight. It would be even smaller, like 8% if we also counted the rind, core and leafy green hat.

component of pineapple

Even though I intentionally did not weigh the full pineapple, I am beginning to wish I had so this data would be even more useful. Next time I promise!




In this series I discuss yield in weight of dried goods vs fresh, and effective cost per pound.

Yield of Dehydrated Bananas


Based on my real world measurements, 1 pound (454 grams) of fresh bananas purchased in the grocery store should yield 2.6 ounces (75 grams) of dried bananas.

Expressed as a percent, your bananas will shrink to 16.6% of their original size. Expressed as a fraction, 1/6.

Note that I include the peel in all of these calculations, for the simple reason that you pay for the peel at the grocery store.

Peels have a number of uses I won’t discuss at length here. They can be left on the bananas for longer and their sugars with leach into the bananas, and they can be composted.


Four bananas were used for this measurement. Bananas were weighed three times.

Once with peels,


Once without peels,peeled-bananas-weight

And once after drying was concluded. Bananas were dried for 15 hours and had chewy, leathery texture.


Your final dried weight will vary slightly based on level of ripeness and final dryness.

Effective Cost of Dried Bananas

Since dried bananas are shrunk into 1/6 of their original weight, finding the effective cost of dried bananas is as simple as multiplying the price of bananas at your local grocery store by 6.

For example, if bananas cost 69 cents per pound, your effective cost of dried bananas is $4.14 per pound. You can compare this cost with the cost of dried bananas at your local supermarket.

Note: Your true cost will be slightly higher based on the wattage of your dehydrator. Lets say I dried exactly 2 pounds of bananas for 15 hours using my 500 watt dehydrator. That means I used in total 7.5 amp hours at 8 cents per amp hour for a total electricity cost of 60 cents, or 30 cents per pound. This figure can be cut in half by drying 4 pounds instead of 2, by the way.