How do Kitchen Compost Bins Work? The Ultimate Guide

This post was last updated in 2023

Do you want to reduce food waste and create nutrient-rich soil for your garden?

Composting is not just for green thumbs; it’s a simple and eco-friendly practice that anyone can embrace.

And it all starts in the kitchen. This is where you generate food waste and where you’ll need a bin to collect it all.

After my review of different compost bins available in Australia, it became apparent that there are so many different bin types out there. It can be hard to choose which one is right for you if you know nothing at all about kitchen compost bins – what function they perform and what features you should look out for.

In this blog post, I cover these points so you have all the information you need to make the right choice. I will be covering the following points:

How do kitchen compost bins work?
How does a bokashi bin work?
Guide to choosing the perfect kitchen compost bin

I’m covering all the things I wish someone told me when I first got myself a kitchen compost bin!

So let’s get into it

How do kitchen compost bins work?

Kitchen compost bins won’t create compost. Instead, they act as a holding station for your organic waste until you can transfer it to an outdoor composting system, such as a compost bin, worm farm or your council’s foods organics bin.

This may be obvious to some, but I have to tell you, I wasn’t aware of this when I first started!

Composting involves the decomposition of organic materials by microorganisms like bacteria, fungi, and worms. This process requires proper airflow, moisture and a mix of different materials to create the right conditions for decomposition. And this process takes time. Months even.

Outdoor composting systems are better equipped to provide these conditions. Only they can break down materials into nutrient-rich compost. And only outdoor composting systems can hold the volume of waste generated over several months.

This is not going to happen in a bucket!

Sorry if this seems super obvious to you but it’s not obvious to everyone. The amount of times I have read negative reviews about kitchen compost bins because food didn’t turn into compost. And like I said, I can’t talk because that’s what I thought 15 years ago when I first started 🤦‍♀️

So while a kitchen compost bin won’t help you create compost, they are still important to have for three reasons:

Collect Food Scraps: Kitchen compost bins are designed to hold various types of organic waste, such as fruit and vegetable scraps, coffee grounds, eggshells etc. If you use bokashi bran you can add proteins like meat, bones and cooked foods (more on bokashi below). You will need something to hold these food scraps before you deposit them into an outdoor compost bin, worm farm or food organics bin.
Minimise Odors and Pests: Since food scraps can generate odours and attract insects, a good kitchen compost bin comes with features like tight-fitting lids, ventilation and sometimes even odor-neutralising filters to stop odours from occuring and keep insects out.
Convenience: Having a designated compost bin in your kitchen encourages the separation of compostable waste from non-compostable items. This separation makes it easier to manage waste and ensures this valuable materials does not end up in landfill, where it will produce methane and contribute towards climate change.

A kitchen compost bin is an essential item in your home compositing system and they are 100% worth it. They play a vital role in temporarily collecting and storing your kitchen waste and will help you maintain a clean and organised kitchen.

How does a bokashi bin work?

In a bokashi bin, your food waste is mixed with an inoculated bran which will help ferment your food waste, breaking it down and accelerating the decomposition process. After a couple of weeks, you will have odourless “pre-composted” waste that can be buried in your garden or placed in a compost bin.

Why bother with this and why bring it up?

If you are composting all of your food waste at home (i.e. not placing it in the council’s food organics bin) and you want to make compost sooner rather than later, then a bokashi bin helps. That has been my experience.

There is a paritcular type of bin that you will need to buy if you want to get a bokashi system going. The bin will need to have the following features:

The bin needs to be large enough to collect food waste over several days/weeks
The bin needs to have a firm secure lid
It can not have any air holes
There is no need for carbon filters
There needs to be a strainer/filter at the bottom of the bin that allows the liquid to drain away from the food waste
Ideally there is a tap that allows you to draw liquid from the bottom of the bin. Although I have found little use for this tap when using our 14L bin so this is not essential.

You will also need to buy some bokashi bran or EM (effective microorganisms). You can buy this online or off the shelf at Bunnings (the bran sold in Bunnings is rubbish mind you). It looks like shredded wheat bran.

As you add food waste to the bin, you sprinkle on some of the bokashi bran. Not too much, usually just one tablespoon or so. You repeat the process until the bin is full.

You can compact the waste as you go along, using a compacting tool that often comes with bokashi bins (or an old potato masher if you like). You want to take out as much air as possible and squeeze out the juice.

If your bin has a tap, the juice that is produced can be extracted. This juice can be diluted and used as a fertiliser in your garden or poured down the drain (it’s meant to be good at clearing out drains).

Once the bin is full you should let it sit for 2 weeks or more so the waste that was added last has time to ferment.

Once that is done the food waste is broken down and can be buried in your garden or your compost bin. And then it will take around 30 days (give or take) to fully break down and turn into compost.

And that is the selling point for me – the fact that in a month, there is compost ready to use.

But there are so many other benefits:

You can collect weeks and weeks worth of kitchen scraps, using a bokashi system
This means fewer trips to the compost pile or food organics bin
No odour is produced when you use bokashi bran, no matter how old your food scraps are
You can add eggs, fish, meat, and cooked foods to the bin. The bokashi system can break this down, so when you add it to your outdoor compost bin, it won’t end up attracting rodents or other pests.

There is a lot more I could write about the bokashi system but that hopefully gives you a good idea on how it all works.

And hopefully this long explanation and calling it a “system” doesn’t scare you off!

All you need is a suitable bin and bokashi bran and that’s all there is to it.

Guide to choosing the perfect kitchen compost bin

The key to choosing the perfect kitchen compost bin is to buy one that encourages you to compost regularly.

Of course, there are several things that influence this and I cover these aspects below.

1. Find Your Ideal Fit 🏡

Choosing the right bin size is crucial.

Choosing the right size is not just about what space you have in your kitchen but it is also about how much food waste you produce and how often you want to deal with emptying the bin.

If you don’t mind frequent trips to the bin to empty your kitchen bin, then a smaller kitchen compost bin should not be an issue for you. You can go for a 5L compost bucket that sits on your countertop and is emptied every day/every two days.

But if you are anything like me and hate the idea of emptying the trash can, then you will want to go for the largest bin you can get. Also, consider buying a bokashi bin because you can have food waste that is weeks old in a bokashi bin and nothing will smell!

I value this aspect so much that I cleared out the area under our kitchen sink to make room for the largest bin possible for our kitchen:

Exactly how big your kitchen compost bin needs to be depends on how often you cook and how many people you have living in your household. So it is diifcult to give an exact figure. You will find that a 14L bin is good for a family of four that eats most meals at home. You can go 3 – 4 weeks before you need to empty a bin that size.

That has been my experience of course. Not everyone lives in a family of four that cooks a lot so it’s all going to vary depending on your circumstances.

I say, go for the biggest bin that fits into your designated space – that is probably the easiest calculation to rely on!

If you have limited space, then you need to carefully consider where you are going to place your bin. There are several options for the countertop, as well as smaller bins that can fit neatly under the sink. I cover all these options in my review of kitchen compost bins, which you can find here.

In the review, you will find a table that lists all recommended bins by capacity and size details. This should help you choose the right bin for you and your space.

2. Lock in a Solid Lid 🗑️

To keep your kitchen smelling fresh and free of pests, look for a compost bin with a well-fitting lid.

If your lid does not fit well, too much of the bin odour will escape and fruit flies will find their way in and make themselves at home. You don’t want that.

Also if you are using bokashi bin, the lid should be well-fitted and without any air holes or filters. You can’t have air entering into a bokashi bin (except for what little enters when you thrown in your food waste).

That is because bokashi is an anaerobic (without oxygen) process, so you need a lack of oxygn to get the decomposition process going.

3. Let it Breathe 🌬️

So I have been harping on the idea of a bokkashi bin a lot. With that you also need to buy, store and use bokashi bran with your food waste.

If that does not appeal to you, then you need to choose a bin with ventilation. The ventilation needs to be “mesh” like – enough to let some air in but not large enough to allow fruit flies make themselves at home.

Proper ventilation accelerates decomposition, prevents unpleasant odours, and creates an environment where beneficial microorganisms can thrive.

In complete opposition to the bokashi system, when you are collecting food waste in a normal kitchen compost bin, you need oxygen. This allows for the odourless microorganisms to grow and prevents smelly bacteria from developing.

Kitchen compost bins often have holes in the top because this lets moisture out and allows air to circulate. This circulation of air will help prevent odours. Your kitchen compost bin will need air holes if you don’t intend to empty your kitchen compost bin daily and you won’t be using bokashi bran on your food waste.

You can even leave these types of bins on your countertop. Your countertop compost bin should not smell if you have a bin that has ventilation built in. Some also come with activated charcoal filters, which are said to help to neutralise odours. These filters are typically washable and do not need to be replaced often.

Admittedly I can not say for sure if carbon filters help reduce odours – reports are mixed. Some swear by them and others say they’re unnecessary. I haven’t tested these myself.

To summarise the last two points, you can keep your kitchen compost bin from smelling in one of two ways – use a bokashi bin along with bokashi bran on your food waste or look for a bin that allows for some airflow. This will prevent unwanted bacteria from growing and producing odours.

4. Material Matters 🍃

What your compost bin is made from is not just about looks; it’s about function and sustainability. Stainless steel bins offer durability and a sleek, modern touch to your kitchen. Ceramic bins bring a charming, rustic feel but can break easily, while plastic bins are budget-friendly and lightweight.

Recycled plastic is also an option. In my review of compost bins, you’ll find a couple of options made from recycled materials.

The best material for a kitchen compost bin would be one that lasts. In most cases, this means going for a plastic bin as most high-quality durable products are made from plastic. Stainless steel is also known to last a long time, although your size options with steel bins are limited.

And if you don’t like to compromise on your eco values, recycled plastic is an option, as mentioned. However, like steel, your options are limited.

For a full list of recommended bins and the materials they are made from, check out this blog post.

4. Effortless Cleanup 🧼

Cleaning your compost bin should be hassle-free. Opt for a bin with a smooth interior that is easy to wash off and wipe down.

Some bins also come with removable inner buckets, which you can easily take out and clean separately. This feature ensures that you can maintain a clean and hygienic bin without any fuss.

Some ways you can keep your kitchen compost bin clean is to use compostable bags or line the bin with paper, making it easier for you to clean out your bin once it is emptied. Cleaning is just a matter of washing the bin in the sink with mild detergent.

Some are dishwasher safe, so they can be cleaned in your dishwasher.

I have a fairly large bin, which I wash down with a hose after I have emptied it in my compost tumbler.

Each bin I considered in my list of recommended products are easy to clean. I cover bins in range of sizes and I have noted which ones are dishwasher safe, so check that out.

6. Tote-ally Convenient 🛍️

If you plan to compost outside, having a bin that’s easy to transport is a game-changer. Look for bins with built-in handles or other carrying features. This makes it easier to take your kitchen scraps from indoors to your outdoor compost pile or bin.

Remember convenience is key to maintaining your composting routine so little things like this can matter.

7. Style it Your Way 💃

Eco-friendly living doesn’t mean compromising on style. Your compost bin can be a reflection of your personal taste and kitchen decor. With options ranging from sleek stainless steel to charming ceramic and practical plastic, you can find a bin that seamlessly blends into your kitchen’s aesthetic.

8. Budget Bliss 💰

Composting doesn’t have to break the bank.

Compost bins come in a wide range of prices, so you’re bound to find one that fits your budget.

But remember that investing in quality can pay off in the long run, as a durable bin will stand the test of time and continue serving your composting journey for years to come.

On the flip side, kitchen compost bins don’t need to be an “investment” for the long term. You can keep things really simple and eco-friendly by reusing any old container as a kitchen compost bin.

As mentioned before, a kitchen compost bin is simply something used to collect food scraps. All you need is a container with a lid. So used ice containers or yogurt tubs could work.

But remember, airflow is key if you want to prevent odours.

Since these containers don’t have air holes, you will need to empty these containers before the food starts to rot.

9. Trust the Good Names 🏆

When it comes to sustainable products, reputable brands matter. Opt for compost bins from trusted manufacturers known for their commitment to quality

Ideally, you would want a brand with eco-consciousness at the heart of their operations. But I have to admit, it’s difficult to find a brand like that in this space.

The best you can do is to look out for well-established brands that prioritise durability, functionality and innovation in their designs. That way, you can be assured you are getting a quality product that will last.

Some brands that fit this criteria include Bokashi One, OXO and Joseph Joseph. They aren’t the cheapest brands out there but if you can afford them, they are the best options, for the reasons mentioned in this blog post.

10. Reviews Speak Volumes 📢

Before making a final decision, make sure you check out all available online reviews and ratings. Through these reviews you can get some invaluable insights into a bin’s real-world performance.

Reading about the experiences of others can help you understand any potential pros and cons, making your decision-making process more informed and confident.

And lucky for you I have done this hard work for you. Check out the results in the blog post linked here.

In conclusion, kitchen compost bins are an essential component in any composting journey – whether you are collect food waste for your council organics bin or using it for your own garden.

By selecting a bin with essential features and embracing effective composting practices, you can start composting with confidence and play your part to keep food waste out of landfill.

It is through these conscious actions, we can collectively work towards a more sustainable future