Can I put moldy food in compost?

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Can I put moldy food in compost?

Also: Is moldy food harmful?

What happens if you eat food with mold on it?

Does toasting bread kill mold?

Will eating moldy cheese hurt you?

Can worms eat moldy food?

You can put moldy food in compost. The first stage of making compost from food-waste is the moldy stage. If you have moldy food, this means that composting has started before the food has reached the compost bin. When you put moldy food in compost, you need to handle it with care to avoid disturbing the spores.

We all come face to face with something that’s gone moldy from time to time. Unless you can appreciate the artistic value of the colours that nature displays when things go moldy, you probably look at it with disdain and just want to put it out of sight and out of mind. You may want to put it in the trash can to be collected but you should be asking: Can I put moldy food in compost?

The good news is that a compost bin, heap or pile is the best place to put moldy food. You may not be aware of what goes on in your compost bin. When you add, what appears to be, fresh kitchen waste or left over food, to the compost heap, it will go through a number of stages as it breaks down. 

Mold is the first stage of composting

In the first stage composting everything goes moldy. Mold spores are everywhere, they will find their way into your compost, you won’t need to put effort into adding it. They find their way onto every surface that you can see. If they land on something that isn’t a suitable source of nutrients, nothing will happen. They can only take root on food materials that have been left exposed to them. Most foods have an element of basic sugars; usually starch.

Put this together with a slight amount of moisture and we have what it takes for mold to start colonizing any surface area of food. It soon becomes clear when food has gone moldy. We are all familiar with the coloured patches that mold will generate. It’s the food waving a flag and saying that this item is way beyond its ‘use by’ date. It needs to be put in the compost.

A compost bin is where you want all the mold-spores that nature can provide. This is where they can be at their most useful. Putting moldy food in with the compost will only do good for the compost process as a whole. So don’t hesitate before putting any moldy food in the compost bin.

Is moldy food harmful?

Is moldy food harmful?

We must assume that moldy food is harmful. Some of the mold spores on moldy food contain harmful toxins that can trigger allergic reactions in some people. If you find moldy food, avoid shaking it because agitation will disturb the harmful spores. Make moldy food damp. Damp spores can’t become airborne.

If you do a good job of managing your refrigerator and larder, you shouldn’t be troubled by things going moldy. The quantity of mold that food will be exposed to will range from none at all to just a small amount. In a basic domestic situation the level of exposure is going to be so small that you are unlikely to ever be put at risk of health problems.

Can I put moldy food in compost? Yes. It’s the best place for it.

Most molds are labelled as harmless but none of them should be handled if you can possibly avoid it. There are some that are on the dangerous list and are, therefore, potentially harmful. It’s all about the toxins that molds contain. One of the most dangerous toxins that you may encounter, although in small quantities, is mycotoxin.

The fungi that carry this present themselves as a blue-green colour and it’s typically found on cereal grains and foods like nuts, that have been exposed to the spores and allowed to become moldy due to not being stored in a manner that prevents contamination. 

For example, if a heap of peanuts are left in the open-air and the air is slightly moist, the nuts will absorb enough moisture for the spores to germinate on the surface of the nuts. You will see quite clearly the blue-green hue that the fungi will display. 

The fungi that generate mycotoxins are the most common that you are likely to see. You can expect to see evidence of it on any grain or cereal foods. It will also show up on most fruit that have gone over. Think of the number of times that you’ve seen a blue patch on an orange.

Drawing up a list of all the foods that you can expect to see that may, at some stage, become moldy is a pointless exercise. It would be quicker to draw up a list of foods that didn’t get it, if there are any.

Any consignment of cereal-foods that show any signs of going moldy should be put out of circulation. If it’s a small manageable amount, it can be put in with the compost to rot down. When you do this, take extra care. When moldy food is moved, this is when the spores become airborne. It’s the spores that are harmful if inhaled. It takes surprisingly little agitation for fungi spores to start floating up into the air and try to head straight for your nose.

To avoid sending spores into the air around a piece of moldy food, the best thing you can do is to spray a fine mist of water over the molded item. Making it wet will contain the spores. Only dry spores can fly. When you’ve saturated it enough, wrap the item in newspaper and put it in your compost bin.

Some people may be allergic to the point of displaying adverse reactions or possibly develop respiratory difficulties. The quantities that you are likely to be exposed to in a domestic situation shouldn’t be too much to worry about. If you take the precaution of making any moldy food damp before handling, you will be reducing the risk to almost zero.

Having said this, it’s possible that you can cut away an area of mold from a piece of fruit and safely eat the remainder. You need to assess the piece. If it’s clearly gone too far, then it will have to be put in with the compost but if there is a chance of saving the good part and your nose tells you that it’s good, then go for it. Remember to wash your hands and the fruit before eating.

What happens if you eat food with mold on it?

What happens if you eat food with mold on it?

The first thing that will probably happen if you eat food with mold on it will be that you will spit it out. If you have a good sense of smell, you probably want even start to eat food with mold on it. If you eat and swallow food with mold on it, the acids in your digestive system should be enough to deal with it.

If you are unfortunate enough to have no sense of smell or taste, then you’re going to have to be extra observant about what you’re eating.

Most of us will know if we are holding moldy food or food that’s starting to turn moldy. We have a sensitive sense of smell and taste. Moldy food has its own distinguished smell often described as musty.The first whiff of mold will tell you that there is something wrong here. But if it does get past the first line of defence and your nose lets you down, your taste buds will ring alarm bells as soon as you put moldy food in your mouth. The immediate reaction will be to spit it out. You won’t want to proceed to eating and swallowing, it will be a natural reaction to just get moldy food out of your mouth. 

It’s unlikely that you will actually swallow food that’s, clearly, moldy but there may be the odd occasion when you do ingest food that’s in the very early stages of going off but it’s not completely obvious. You may have eaten something that leaves a strange taste after you’ve put it in your mouth. You may wonder whether you should have eaten it at all. 

If you experience this sort of sensation, then you’ve probably eaten moldy food. Should you worry? No. Any mold material that may be on the food that you’ve swallowed will be subjected to the digestive enzymes and acids that are found in our digestive systems. 

The concentrations of mold in a mild case of moldy food, won’t be enough to challenge you. There may be a small amount of toxins released from the mold material which will have to be disposed of by the body’s own natural methods of removal.

Does toasting bread kill mold?

Does toasting bread kill mold?

Does cooking kill mold?

Toasting bread will kill mold but it may not kill all the mold in the bread. The toasting of moldy bread may release spores. Toasting bread that has mold on or in it, won’t disguise the fact that the bread is moldy. You will probably smell or taste the mold in moldy bread.

If you have bread that you know has some mold about it, it’s better not to be tempted to toast it. Have a cut-off point and put it in the compost. Your compost bin awaits anything that’s a bit ‘iffy’. It’s what your compost bin is for.

Will eating moldy cheese hurt you?


Will eating moldy cheese hurt you?

Eating moldy cheese won’t hurt you but it will depend on the mold and type of cheese. Some cheeses are cultured to contain molds e.g. Stilton. Some people are allergic to moldy food and need to avoid all moldy cheese. Eating moldy cheese, that shouldn’t be moldy, can be avoided by trimming off mold that’s in view.

The odd bit of mold that you find on hard cheese shouldn’t be a problem. You need to look closely at the type of cheese that you’re handling and how long it’s been in the refrigerator.

Cheese is made to go moldy

The thing about cheese is that if anything was designed to go moldy, cheese ticks all the boxes. Cheese has everything needed to culture the perfect mold. This is why some cheeses are so famous for their display of molds and they are put forward as being edible in their molded form.

There are blue veined cheeses which, if anyone didn’t know it, could be taken as cheese that’s gone off big-time. It’s a lucky thing for those of us who know it, that these are some of the tastiest cheeses out there. The mold on these cheeses won’t hurt anyone but there may be a few unfortunate cases where some are allergic in some way.

The molds found in blue cheeses will contain toxins but they have been found to be no serious challenge other than causing the occasional weird dream.

You need to be careful with soft cheeses

The cheeses that carry the biggest risk are all the soft cheeses. We tend to put all our cheeses in the refrigerator and forget about them. For most cheeses this isn’t too much of a problem. Cottage cheeses and cream cheeses are the type of cheese that you need to watch very closely. You need to check the dates very carefully and don’t be too ambitious about expectations of keeping soft cheeses around for very long.

Soft cheeses are famous for offering the risk of some really harmful bacteria. There’s a list to watch out for. The top of the list must be listeria followed by salmonella, E coli and others. You just need to know that eating soft cheeses that are past their use-by date can lead to big trouble and bad illness.

A soft cheese that looks and smells as though it’s starting to go moldy, must be disposed of. It can be put in the compost bin. Sprinkle some hydrated white lime over it to deter any interested rodents that may see you putting it in with the compost.

You can trim mold from hard cheese

It’s quite common for patches of blue mold to appear on hard cheeses. This can often happen when the plastic wrapping isn’t sealed properly and air has got in. This can happen even if you’ve put the cheese in the fridge. Mold spores are everywhere so we shouldn’t be surprised to see anything go moldy.

I’ve seen hard cheese with blue moldy patches, it looks awful but it can be recovered if you catch it in the early stages. I take a sharp knife and slice away the outside of the cheese, leaving the clean, internal part. Don’t scrape the mold from hard cheese, cut it. This type of mold won’t penetrate into the cheese it will stay on the surface, at least in the early stages.

Can worms eat moldy food?

Can worms eat moldy food?

Worms can’t eat moldy food but they can eat the mold that’s growing on the moldy food. When food is going through the moldy stage, it’s too hard for worms to eat. Mold that’s on moldy food is soft and can be grazed by worms. Food that’s passed the moldy stage will begin the rotting stage where worms can eat it.

To worms, mold is like grass to a cow. The mold extracts nutrients from moldy food which is then made available to the worms. The mold on moldy food will often display a variety of fine hair-strands that we see when anything goes moldy. These fine hairs on moldy food are soft enough for worms to eat.

Worms eat the mold on moldy food

When we make compost from any organic material, one of the first things that will happen is it will turn moldy. It will be the surface area that will become moldy. The inner parts of anything destined for compost, won’t become moldy until the outer material has broken down enough. This will allow air to move in and open a way for mold-spores to move in. Eventually, everything in a compost bin, heap or pile will become moldy. 

Worms will turn any moldy food into compost

While moldy food is being broken down by mold the worms will be living in the compost that’s already gone through the moldy stage. In most compost bins, the latest addition of moldy food or organic waste from the kitchen, will be on the surface of the compost.

This is the ideal place for it. There will be enough air and moisture for mold to culture. Mold grows very quickly. In a domestic compost bin there will be enough time for a consignment of food waste to go moldy and become food for worms before the next delivery to the compost comes along.

Multi-tray wormeries are designed to allow for food to go moldy on the top tray, while the worms are busy in the lower trays of compost. Each tray will be at different stages of becoming compost. The most complete compost will be the tray that’s at the bottom of the stack. The freshest material will be in the top tray and there will be compost forming from the top down. Each tray will have compost that will be at varying stages.

Making compost the Rolypig way

The Rolypig composter also works as a wormery. Initially designed as a compost tumbler, the Rolypig is fed at the mouth end and finished compost can be removed from the back end. This is an in one end and out the other composting system.

Unlike most compost tumblers, the Rolypig composter sits directly on the ground rather than being on a stand. This allows worms to have easy access into the barrel. The barrel is made from two halves that are held together by stainless steel bolts.

The join between the two halves of the barrel is not a complete seal. This allows worms to get through and take up residence in the compost. The Rolypig composter never needs to be emptied. You only need to remove compost when it becomes so full that you need to remove some to make more room for fresh kitchen waste.

The Rolypig composting system works best when the barrel is full. This allows for the worm population to be at its maximum at all times. This will ensure that any fresh kitchen waste that’s added, will have plenty of worms waiting to get at it at the moldy food stage and there after.

When we say that the Rolypig needs to be full, it should be noted that in practice, the barrel can only ever reach a state of being half full of compost. This is due to the nature of the input point for fresh kitchen waste, being where it is. 

The barrel of the Rolypig is relatively easy to roll over even when the compost level is at maximum capacity.

If you aren’t impressed by the multilayer system wormery or the Rolypig composter, you can easily make compost in a standard compost bin. These don’t cost as much but there is a bit more work and you may need to have more of them because the compost tends to stay in them for longer.

Compost bins can work as wormeries

Compost bins that have an open base, most of them do, can also work as a wormery. They have easy access that takes them from the ground, straight into the compost. In the right conditions they will occupy the entire mass of developing compost in the bin. When kitchen waste is put in on top of the compost that’s building up, the worms will move into it when the mold appears and so the story goes on.

When food in compost has finished going through the moldy food stage, the remaining material will be soft enough for worms to digest. They will burrow through it and after a while, what started as moldy food waste being put in the compost, will become completely unrecognisable.

Some people make the mistake of believing that moldy food will generate toxins that will be detrimental to worms. There may be a period during the early stages where moldy food will be unattractive to worms. The freedom of a composting mass will allow worms to avoid any areas where there may be toxins produced from moldy food. 

There is also a belief that any moldy food needs to be broken up for the mold to work its way into the general composting mass. This isn’t necessary. Compost will form from moldy food without any interaction from anyone.

Food to us is food to most other living organisms and life forms. Mold spores are everywhere. The process has been going on for as long as you can imagine. When moldy food is placed in compost, everything will happen by itself. 

Moldy food will attract the interest of worms but it doesn’t matter if there are no worms in the compost. It’s not a requirement that there are worms in attendance to deal with moldy food. If there’s nothing there to eat the moldy part of moldy food, the mold itself will break down and become part of the compost.

Compost will form without worms

With no worms present, moldy food will continue on with the process of turning into compost due to the actions of a variety of microorganisms that are always found in soils and the environment generally.

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What else would you like to know?

Can you put meat in compost?

Can you put coffee filters in a compost bin?

Is rice compostable?

Can you put Citrus in compost?

Can all food waste be composted?

Can I put cooked potatoes in the compost?

 What can you put in your compost bin? What is a compost accelerator? Can you put grass clippings in compost?

 Can I put urine in my compost bin? Smelly Compost How do leaves decompose faster?

 Do worms help compost? What does lime do to compost?What do I add to compost to help break it down?

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Molded fruitMoldy foodMoldy orangeMoldy breadMoldy cheeseMoldy nectarinesWorms


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