Eat the peel: Why you might be throwing away the best part of your fruit

It would be unusual to needlessly throw away one-third of the edible part of a banana every time you eat it.

But that's exactly what most of us do when we throw away the peel, which makes up about a third of the average weight of the entire fruit.

Banana peel, like many other fruits and vegetables, is not only edible but also contains beneficial nutrients.

When it comes to oranges, about 20 percent of this fruit is peel – in 2018, about 15,1 million tons of orange peel were thrown away, according to one study (that's almost 80.000 blue whales or 2,500 giant sequoias).

In kiwis, between 9 and 13 percent of the fruit is peel.

A pomegranate has almost as many peels as seeds.

Globally, about a third of food is wasted or lost, which amounts to about 1,3 billion tons per year.

Food loss and waste account for eight percent of global greenhouse gas emissions (more than a third of aviation's contribution).

Organic matter rotting in landfills also releases huge amounts of methane, a potent gas 80 times more potent than carbon dioxide (CO2) over a 20-year time period.

• Frozen, fresh or canned foods: Which are the most nutritious
• Medlars, a forgotten medieval fruit with an obscene name
• Food control in Serbia: Where do the pesticides on the plate come from?

Composting food waste instead of sending it to landfill can help reduce the amount of methane released into the atmosphere.

But much of what we perceive as waste is actually perfectly edible.

Within the food industry, there is growing interest in better utilizing both the nutrients and energy in the peel that is usually discarded.

But there are ways to do it at home.

Probably one of the easiest ways to use the peel is in recipes that call for all parts of the fruit, not just its flesh – such as banana cake and its peel.

Here are five more options for preparing food from leftovers that are too often thrown away.

Orange peel

After the Christmas holidays, I had a huge bowl of leftover oranges, so I thought I'd make marmalade for the first time in my life.

Marmalade is a breakfast staple in my house – I always start my day with a strong English breakfast tea and a piece of buttered toast with this orange spread.

I found a recipe for BBC Good Food for "the English classic that made Paddington Bear famous," which sounded nice and simple.

There were only three ingredients: Seville oranges (1,3 kilograms), the juice of two lemons, and a frankly shocking amount of granulated sugar (2,3 kg).

I quickly realized that making marmalade is neither particularly quick nor easy.

It took me three hours to make two jars and involved quite a few steps, including two hours of simmering the oranges, straining the pulp through a sieve to release the pectin (a natural starch that helps thicken the marmalade).

Then I added sugar and chopped zest, and boiled this orange mixture for 20 minutes.

That clearly wasn't long enough, because although my marmalade looked and tasted good (it wasn't too sweet or too bitter), it remained very runny – meaning it wasn't exactly ideal for spreading on my toast.

But I discovered a new, cute breakfast option: marmalade with Greek yogurt.

I had a few oranges left, so I decided to make candied orange peel by chopping the peel and blanching it in boiling water for 10 minutes.

You need to repeat this process three times, rinsing the peel with cold water each time to remove the bitter taste, before adding the sugar and water.

The candied orange peel was delicious – the perfect sweet treat.

I also had some delicious orange syrup left over that I used as an addition to drinks.

I'm pleased that I managed to turn that bowl of oranges into four delicious food items: marmalade, candied peel, a glass of juice, and orange syrup.

An added bonus was that my kitchen smelled amazing – filled with the delicious aroma of oranges.

Pineapple peel

When you eat pineapple, you always feel like you're throwing away too much.

There seems to be more waste from the pith, peel, and top than there is actual fruit.

This time I decided to use that bark.

Tepas is a historic Mexican fermented drink that dates back to pre-Hispanic times.

It not only uses up all that waste, but is also a source of probiotics.

The recipe is fun – and easy – to make, but be careful if you avoid drinking alcohol, because the fermentation process means there is some alcohol present (though usually less than one percent, depending on the fermentation time – the longer you ferment the drink, the higher the alcohol content).

I used a 3,8 liter jar, a large elastic band, and a piece of muslin or gauze large enough to cover the opening of the jar.

First, I washed, peeled, and cored a pineapple (organic fruit reduces the risk of pesticide residue on the rind).

Then I mixed brown sugar or piloncillo (traditional unrefined cane sugar from Mexico) into the water in a pan and heated it over low heat until all the sugar dissolved.

Then I let it cool a bit, and added the pineapple core and peel to the jar, then added the water and sugar mixture while it was still warm.

Then cover it with muslin, cheesecloth, a tea towel, and baking paper – basically, you need something that will keep flies away from your work while allowing air to get in.

Then I left the mixture to ferment.

I was advised to leave the tepaš at a temperature between 21 and 25 degrees Celsius and to check it constantly – after 24-36 hours you should have white foam on top, which means it is fermenting.

The longer you leave it, the stronger the flavor will be.

As soon as it was ready, I drained the liquid and left it in the fridge to keep the drink refreshing.

Tip: you can add ginger, lime, and other fruits for an extra, richer flavor.

(But if you're adding an acid, such as lemon or lime, don't do it until the mixture is ready, as this slows down the fermentation process.)

Ginger peel

Ginger peel is also often thrown away as food waste.

But it's the peel that gives ginger so many of its beneficial qualities: the peel contains biochemical compounds that have phytochemical properties, including antioxidant, antimicrobial, and anticancer effects.

Ginger peel is a rich source of fiber and vitamins, including vitamin C, calcium, iron, and others.

So, if you don't want to throw away the peel, how can you use it?

You can simply use ginger normally, with all the peel on (in fact, very few recipes specifically say to peel the ginger), or you can use the peel in some other recipes.

Add it to soup to enhance the flavor (but remove it before blending or serving).

Boil it in water to make ginger soup, which can be kept in the refrigerator and added to smoothies, juices, cocktails, mineral water, or used to steam beets for a stronger flavor.

Or for a richer flavor, roast the peel over low heat in the oven and grind it into a powder (either using a blender with a small grinding attachment or in a coffee grinder).

You can use the powder to brew delicious ginger tea – just make sure to strain it once it's brewed.

The powder can also be used as a spice in cooking or baking.

Tip: use a teaspoon to peel ginger instead of a peeler.

Butternut squash peel

Many recipes call for winter squashes like butternut squash to be peeled before use, but the skin of the squash is perfectly edible, as are its seeds.

Both are a good source of fiber as well as vitamins and other bioactive compounds.

I usually leave the skin on the butternut squash, but throw away the seeds, because it seems too much work to clean them.

I wanted to try something completely new, however, so I decided to roast the peel and seeds to make some, I hoped, crunchy homemade chips.

I started doing this one night while I was cooking dinner, using butternut squash from the vegetable section of my local grocery store.

I washed it thoroughly and then dried it, then cut off the top and bottom.

Then, using a vegetable peeler and a knife, I removed as many thin pieces of peel as I could (mostly with the knife, because the vegetable peeler wasn't really doing the job), which took me about ten minutes.

I ended up with a mix of different pieces that looked perfect for bite-sized chips.

Then I opened the pumpkin lengthwise and scooped out the seeds from the center and the gooey and fibrous pulp around it.

I put both them and the peel in separate compartments in the fridge overnight and used the peeled pumpkin to make pumpkin and paneer curry.

The next day, while I was making coffee and feeling hungry, I separated the seeds from the pulp.

I was afraid of this part, but they actually came apart very easily.

I washed the seeds thoroughly, then wrapped them in a clean kitchen towel to dry.

Then I repeated this last step after my partner took a cloth to dry his hands and scattered the seeds all over the kitchen floor...

I mixed the seeds and pumpkin rind together in a bowl with a little salt, paprika, smoked paprika, cumin, and chili seeds, and then mixed in a few drops of olive oil.

I cooked all of these using the bake option on my air fryer at 170 degrees Celsius to avoid overcooking them and checked them frequently.

After about 20 minutes, it looked nice and crispy.

I was still a bit skeptical at that stage – but they were excellent.

The smaller pieces turned out to be the best because they were extremely crunchy and the seeds had a fantastic flavor.

I liked that I could choose what seasoning to put on them, but I think the ability to use nice olive oil was what put them miles above store-bought chips.

They would also be a fantastic garnish for soup.

Overall, however, it did seem like a lot of bullying for not much food.

Next time I would make sure to separate and wash the seeds in advance, and I would also check them less now that I know how long they take to cook, which would make this an easier snack to prepare.

It was useful to use an air fryer, because turning on the entire oven for this amount of food would have seemed like a waste of energy.

I really liked the final result, though, and it was really generous, and I would definitely use it again for any occasion when I had the patience to exfoliate.

For a harder peel, remember that the peel can be stored in a freezer bag with other edible vegetable scraps and used for vegetable stock.

Onion peel

Papery onion skins are another outer skin that we usually don't think much about before throwing away.

I saw on social media how people dried out onion waste and ground it into powder, so I tried to imitate that.

I set aside the dried outer layer of yellow onion skin for "pulverization."

In short, after several hours of drying onions in the oven and then throwing them into the chopper, the outcome was disappointing.

In the end, I had to add salt to revive the flavor, and then add the resulting mixture to the general spice mix in which the onion flavor was muffled.

Since I still had some onion skin left, I turned everything in a completely different direction.

Like many other peels, onions contain chemicals called flavonoids, which have antioxidant and anti-inflammatory properties.

These flavonoids can be boiled and extracted from vegetables, producing a strong dye for painting.

Tannins (the same type of molecule that gives wine its dry taste) can also be found in the outer, fluffy layer of onions, while its bitter taste repels hungry critters.

But in the same way that wine stains are a pain to get out, onion tannin is an effective dye for fabrics like cotton and linen, which usually need to be prepared with a fixative called a mordant to ensure the dye will last.

First, I washed the fabric (I used a clean sock) in a warm bath to remove any residual oil or dirt, which could affect the effectiveness of the dye.

After air drying the fabric, I tossed the onion peel into a large metal pan with about two cups of water (adjust the amount of dye and water depending on how large the fabric is).

I boiled the bark over medium heat until it boiled and let it simmer for about 15 minutes, until the water turned a dark amber color.

When the fabric is mostly dry, turn off the heat and remove the onion skins with a slotted spoon.

Soak the fabric in the hot dye solution so that it is completely covered and leave it for 30 minutes to an hour.

Without wringing the fabric, leave it in a cool place to dry.

If the amber color of the fabric is not strong enough, repeat the dipping process until you achieve the desired color.

I was pleasantly surprised by the results of the experiment and plan to repeat it.

My sock turned out an autumnal orange, but with the use of different types of bows or mordants, the fabric can turn out from bright yellow to muted green.

BBC is in Serbian from now on and on YouTube, follow us HERE.

Follow us on Facebook, Twitter, Instagram i Viber. If you have a topic suggestion for us, please contact bbcnasrpskom@bbc.co.uk