7 Food Scraps You Should NEVER Throw Away: How To Reduce Food Waste

This post is part of the Eating on a Budget series, which includes the essential tools, tricks and tips that underpin eating on a budget, and a collection of recipes to put those tools into practice.

One of the many reasons that I love cooking is that it’s an endless opportunity for creativity. There’s tonnes of different dishes to cook, and tonnes of ways to prepare any given dish and there’s an endless list of fruits, vegetables and ingredients out to experiment with. Almost every time I cook, I discover something new.

But that’s less often the case these days. At the time of writing, my girlfriend and I are travelling around New Zealand — and we’re on a very tight budget. This means that my creative focus in the kitchen has shifted from exploring interesting ways to prepare dishes to finding clever and frugal methods to make the most out of the food we already have.

This journey of maximising the value from the ingredients we have has led me to realise that many food products that we generally perceive as waste — such as cheese rinds, leftover juices and woody cuts of vegetables — are actually useful ingredients in the kitchen or, in some cases, are food in their own right. It’s a great way to reduce food waste, and save money.

And that’s exactly what we’ll be discussing in this post — we’ll explore 7 waste food products that can be used (or re-used) as ingredients in the kitchen to help reduce food waste.

#1: Broccoli stems

Brassicas — the botanical plant family that broccoli belongs to — is the absolute king-pin of the vegetable world. Cabbage, Brussels sprouts, cauliflower and kale all fall into this group which all evolved from the same ancient cabbage. Brassicas are delicious and versatile vegetables that are as ubiquitous in my cooking as they are varied. This is especially the case with broccoli.

But while kale, sprouts, and cabbage are generally used in their entirety (aside, perhaps, from the cores), most of a head of broccoli is wasted.

Most people prepare broccoli by cutting the florets from the head of fresh broccoli, and then throwing the stem in the bin.

Recently, I’ve come to believe staunchly (as anyone does after forming an opinion for just 5 minutes) that broccoli stems are just as flavourful as the head — if they’re cooked right.

The recipe linked gives clear instructions on how to prepare broccoli stems to maximise their flavour, but the crux of it is that the broccoli stems need to be cooked for longer than the heads so that they are given enough time for their woody, fibrous stems to break down and caramelise.

#2: Aquafaba (pulse juice)

Aquafaba (which literally translates to water bean in Latin) is a term recently coined to describe the starchy (and rather unappealing looking) liquid that comes packed in the tin alongside chickpeas and other pulses.

But what is this mysterious liquid, and why is it so useful? In short, it’s simply bean juice.

Beans are made up primarily of starch. As the beans are cooked in water, they release their starch into the water — and what’s left when you take away the beans is aquafaba. It’s the stuff that chickpeas are tinned in, and its what would be left if you cooked chickpeas (or other pulses) yourself.

This glorified bean juice has been celebrated widely over the last few years after a French chef discovered that it has a bunch of useful applications in the kitchen.

First and foremost, it is a powerful substitute for eggs.”It works particularly well as a replacement for egg whites, and in some contexts, it can also replace the whole egg. That means that you can use aquafaba to make:

• Vegan-friendly mayonnaise
• Desserts, including meringues and macarons
• As a replacement for eggs in baking recipes, such as carrot cake
• Foam (I guess…)

It isn’t yet known exactly which attributes of aquafaba make it such an efficient egg substitute. But it’s definitely interesting to see new food discoveries being made in a time when it feels as though every element of cooking has been uncovered, and it’s a great way to reduce food waste.

#3: Hard-cheese rinds

Parmesan and similar hard, aged cheeses (such as Grana Padano and Pecorino Romano) form a rind on their exterior that hardens as the cheese ages.

These rinds are edible, but they’re generally too hard to gnaw on — and that’s a shame, because they’re generally as flavourful as the rest of the cheese. They’re easily my favourite way to reduce food waste.

But there is a solution. Instead of throwing away these umami-rich ingredients (as I have been guilty of many times in the past) there’s a bunch of things we can do with them.

The easiest way to use them is to toss them into a stock or a soup. The water will absorb all the flavour from the rind, and then you can discard it when the stock or soup is ready

Chef Theo Randall notes that, thanks to hard-cheese rinds, he rarely uses stock cubes. “I just use water and a parmesan rind – it’s like a little flavour bomb,” he told The Guardian — alongside a bunch of other tips to help make use of your parmesan rinds.

To make a delicious cheesy snack, he suggests that you “char the outside of the rind, then scoop out the cheese with a teaspoon; it will have melted and taken on a nice, smoky taste.”

I tried this by charring a leftover rind directly over a gas flame on my hob… and I managed at least to trigger my fire alarm — but it was definitely worth it.

#4: Vegetable offcuts

Prepping vegetables invariably leaves you with offcuts — the scraps of the vegetable that are generally undesirable, and thus get thrown away. Think carrot skins, onion roots and celery heads.

But while these vegetable offcuts aren’t very fun to eat, they’re still useful to reduce food waste — you can use them to create vegetable stock.

I’ve wrote about this process in another post, but the crux of it is that you preserve all these offcuts in a zip-lock bag in the freezer. Over time, this bag builds up.

Once you’ve hoarded enough scrap veggies, you boil them for 10 minutes in a stockpot filled with water and then strain the mixture. What you’re left with is a basic vegetable stock that you can use for soups, stews and the like.

#5: Pickle juice

Pickles, such as gherkins, are stored in a salty water/vinegar solution that keeps the pickles preserved. These acidic and salty environments are not conducive for bacteria growth, and so they stop the vegetables from rotting away.

While pickling isn’t as common these days as it has been historically, pickled products, especially gherkins, are still popular.

And this pickle juice can be re-used once the pickled product has been eaten. You can create a fresh batch of pickled vegetables by boiling the solution, then submerging new vegetables in it and letting it cool.

What else can I say? Go make some pickles.

#6: Various leftover liquids

Many liquids that we typically consider kitchen waste actually have useful applications. We discussed earlier that aquafaba can be used to make mayo and meringues, and that we can re-use pickle juice to make, well, pickles.

But the list doesn’t stop there. Pretty much any other flavourful liquid you can think of can be used in any recipe in place of water. These “juices” can often be used as the liquid for soups and stews, for blanching vegetables, boiling rice and pasta, etc.

These solutions are often salty, and thus you need to be mindful of how much salt you add to these foods, but they’re essentially flavourful juices that we’re just wasting when we pour them down the drain. But this helps to reduce food waste even more by saving salt (if only a smidgen).

A few examples of these “juices” are:

• Acid whey: the by-product from paneer making
• The liquid that cheeses, such as feta and mozzarella come packed in

#7: Animal fat

If you’ve cook any high-fat cut of meat for a long time, you’ll eventually render the animal fat from the meat. This means you’re removing the moisture from the fat and making it shelf-stable.

As the meat and the water it has been cooked in cools, this rendered fat usually sits on the top of as a white layer.

The common thing to do with this fat is to scrap it off and toss it. But that’s a massive waste. This fat is some of the most flavourful s&%t you can find.

It can be used as a replacement for fat in any context — on roast potatoes, as the base of sauces, in mayo, etc. (If you mix that fat with aquafaba and some of your leftover mozzarella or feta juice, you’ll have a mayo made exclusively from by-products).

You can even use animal fat to infuse your alcohol, a process known as washing.

To make animal fat properly shelf-stable, let the meat and water cool to give the fat time to separate from the water (fat sits on top of the water as fat is lighter than water). Then scrap off the layer of fat and add it to a pan. Slowly heat it up until it turns liquid, then pour it through a strainer lined with a paper towel.

Congrats — you’ve now got the most delicious cooking fat you could ever want.

Bottom line: reduce food waste

There are a bunch of different food products that I used to throw away, but which I now realise are so useful in the kitchen.

This information has helped me to reduce food waste, which in turn has helped me save money and its made my cooking better too. I mean, who doesn’t want the flavour of parmesan in their soup?