Can I put moldy bread in compost? – compost starts with mold

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Can I put moldy bread in compost?

A question that comes up from time to time is: can I put moldy bread in compost? Yes, you can put moldy bread in compost. The first thing that happens to any organic material when it’s added to a compost bin is that it will turn moldy. You won’t necessarily notice this because the mold stage in compost comes and goes quite quickly, often occurring between visits to the bin.

A compost bin is the best place for moldy bread and anything else that’s gone moldy.

The mold will not adversely affect anything in a compost bin or tumbler. Adding anything that’s moldy to waste that’s destined to become compost will help with the process.

Can I put moldy bread in compost? Yes, compost starts with mold.

Mold spores are everywhere, including in the compost bin, and one of life’s major challenges is to stop foods of any kind from succumbing to a premature end through molding and then have to be discarded.

Mold appearing on kitchen waste in a compost bin will be the first stage in the breakdown process. You won’t need to actively add mold spores to compost, they will just turn up.

If you have worms in your compost then they will be delighted if anything moldy turns up. They actually eat the mold fungus that’s generated from the molding process. This maybe why you don’t see mold in a compost bin because the worms get at it before you get to see it. Fungal material is soft and therefore easy for worms to bite at and digest.

What else?

What will happen if you eat moldy bread?      Can you pick the mold off of bread and still eat it?

Is mold on bread the same as penicillin?      What do you do if you eat mold?

How do you keep bread from getting moldy?    Can you get sick from eating stale bread?

Is there white mold on bread?    How does a piece of bread become moldy?

How long does it take for a piece of bread to mold?    What is calcium propionate?

Can you put moldy food in worm compost?


Will bread in compost attract rats?

Yes it will if it doesn’t rot down quickly. The thing is with bread, especially if it’s moldy, the decomposition is under way before it’s placed in the bin. All you need to do is to make sure that the moldy bread is dampened and it will start to rot. Unless you have a family of rats that have taken up residence in your compost bin, it will take them a while to realize that there is any bread there. A fast rot will leave nothing to attract rats or mice.

If you leave it in the bin in a dry state they will sniff it out. They will be in there and make off with it and you won’t know that they’ve been in unless they’ve chewed a hole in the side of the bin. The main problem with this is that rats are creatures of habit, If they have found something tasty once then they will get in the habit of coming back again to look for more.

So, if you have moldy bread to dispose of, put it in the compost bin and splash some water over it. This will turn a food fail into useful compost, so it won’t be a complete loss.

 What will happen if you eat moldy bread?

This would be risky. If you take a chance and eat just slightly moldy bread then you run the risk of a reaction happening which will vary depending on your own sensitivity. You may experience breathing problems from a mild ingesting of the fungal spores. You may suffer from irritations in the nose, throat or mouth. You may go to into an episode of anaphylactic shock leading to very serious consequences. This is scary! Mold on bread can make you ill.

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We really need to rely on our common senses of sight, smell and taste. The sight of anything that looks like it’s gone ‘off’ is usually enough for most people to give it a miss and throw it out.  Some will tell you that moldy bread has no unusual taste or smell. I wouldn’t know about the taste of anything moldy but I do know that there is enough of a smell with anything moldy to raise the alarm.

It’s difficult to see how anyone can accidentally eat moldy bread or anything else that’s gone over. This could only happen to someone who is unfortunate enough to have very poor eyesight, no sense of smell or taste.

There is usually a definable smell with moldy foods which I, and others, would refer to as fousty. If you breath it in you can feel it in your lungs and you just want to move to fresh air. If you get this sensation with foods that have gone off then play it safe and put in the compost.

Can you pick the mold off of bread and still eat it?

This wouldn’t be wise. If there is any mould appearing at all on a loaf of bread, take this as an indication that it’s become established. What you can see, often as a blue patch, will be generating fungal spores. These will be spreading around and are sure to be on the bread that looks clear. Tempting though it may be, if you proceed to eat that bread then you risk ingesting these spores which surely won’t do you any good.

Is mold on bread the same as penicillin?

Some will say that a bit of mold on bread is just some naturally occurring penicillin and it won’t harm you. Unless you know the chemistry that goes on involving the range of toxins that fungi generate, it’s wise to view the subject with plenty of suspicion.

It’s true that the known antibiotic, penicillin is produced from mold fungi but it’s a specific type of mold that does this. A layman won’t necessarily know which mold fungus is present on any molded bread. If you have it in mind to use any of the raw mold material to treat yourself then don’t.

The mold fungus that you are looking at will be generating all manner of toxins which may have medically advantageous properties but unless you’re an expert in the field the only advice from anyone can be leave it alone. If you have a wound or infection of any kind, for goodness sake go and get professional medical advice.

What do you do if you eat mold?

If you have swallowed some moldy bread, don’t panic. Most of the fungi that grow on bread, apparently, don’t produce toxins that cause an immediate threat to health. That having been said there is a risk for some who suffer from allergies or have any problems with the immune system.

If you have eaten anything that has turned out to be something that should have gone in the bin, you will probably start to suffer the consequences soon after. If you have any concerns after having ingested bread or any food that’s clearly ‘off’ then seek medical advice.

How do you keep bread from getting moldy?

In a word it’s ‘management’.The first thing you need to know is how much bread will you need available to you in the next day or two?l Most people have their regular number of slices of bread that they consume over a specific period of time. So it shouldn’t be too difficult to figure out how much to have out and available. The best way that I have found to preserve bread for long periods of time is to freeze it. It will freeze very easily and won’t deteriorate unless you leave it in a freezer for a long time, in which case it will become dried out.

If you only need a half loaf in a day then why not cut a number of loaves in half? Freeze them all and only take out what you need for the next day. Bread should last for a couple of days. It may dry out in that time but it shouldn’t go moldy.

Another thing to consider is to make your own bread. I’ve noticed a difference between the bread that I make and, what I call ‘shop-bought’ bread. Bread that you buy at supermarkets tends to be more moist. The higher water content makes the bread more conducive to becoming moldy. They probably make it more moist to allow for drying out.

By making your own bread you have control over the ingredients. One important ingredient that will reduce the onset of molding is salt. There have been some health scares about having too much salt in our diets. We do need to have some salt. Bread doesn’t have much flavour if there isn’t enough salt and it will prolong the life of a loaf.

Can you get sick from eating stale bread?

I’ve never heard of anyone becoming sick from eating stale bread. There is a difference between stale bread and moldy bread. If there is mold then it will be evident without question. You will smell the mold if there is any. Stale bread will most likely be bread that has dried out. This won’t do you any harm if you eat it. Dry bread is unlikely to be moldy as mold fungi needs moisture to form a culture. All foods have a best before date in nature. It isn’t just what is printed on any packaging.

You have to use your own judgement when deciding if a food item has crossed the line and should be thrown out. Very often when a food item is nearing the point where it can be classed as stale, there will be a change in flavour which will become evident when in the mouth. In most cases the test to establish whether foods are stale beyond recovery is to use your nose before thinking about eating it.

Is there white mold on bread?

Watching the progress of molds forming on food is a display in itself. It can be quite colourful depending on the type of nutrients in the food that’s being colonised with mold.

In the case of bread it very often starts with a white fluffy mold. This then progresses into pale blue and then into black spots. This happens as the bread is broken down in stages. At the first sight of the white mold you should discard it because at this stage it will be generating a high volume of spores. When released into the air around, these spores will pitch on other foods and try to colonise here as well.

How does a piece of bread become moldy?

From the moment a loaf of bread finishes cooling down after baking, it’s vulnerable. There are fungal spores in the air which land on everything, this is why they are so successful at surviving. When they land on something that provides a base that has all the ingredients needed to form a colony they root themselves in and the next thing you’re likely to see are pale blue spots on your piece of bread. This is the ultimate indication that your piece of bread has been successfully invaded and taken over by mold.

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The conditions have to be just right for fungi to thrive. If you have ever tried growing mushrooms you will know that achieving the right conditions is almost impossible. Luckily for the type of mold fungus that turns up on bread, the conditions are ideal from the moment it’s cooled from the oven.

This type of mold needs moisture but not too much. The temperature has to be within a band range that includes room-temperature and there needs to be a combination of the required nutrients that molds need to feed from throughout it’s propagation. Bread provides all of this, it is the perfect medium for fungus to grow. The very structure of bread is ideal for mold fungi to grow into it because it is soft and made up of small bubble cavities and there is enough moisture inside a loaf to allow for a full progression throughout the whole loaf.

So, you may be wondering, how can you stop a piece of bread from becoming moldy? If you bake your own bread, as I do, the best way to keep on top of the problem is to freeze the loaf as soon as it has could from the oven. Put it or them, if you bake a batch, in plastic bags and put them in the deep freeze. This will preserve bread very successfully and when you take it out and thaw it, it will have a smell and taste as though it were fresh baked.

The same can be done with shop-bought bread but bare in mind that you may not be freezing bread that’s as fresh as having home baked. Shop-bought bread, these days, is often supplied in a plastic bag and largely protected from invading fungal spores so it shouldn’t be too much of a problem. Just make sure that when you receive or collect your food shopping that you put the bread in the freezer as quickly as you can.

How long does it take for a piece of bread to mold?

Expect mold to appear on a piece of bread from two to five days after being baked but this will depend on where the piece of bread is being stored. It will also depend on whether it’s  a piece of bread bought from a store or your own homemade variety. If it’s stored in a bread bin for any length of time it will start to mold much earlier than if you store it in a fridge. A lower temperature will definitely slow the molding process.

Homemade bread will respond differently compared to bread from a store.

Homemade bread tends to have a higher moisture content and, because you’ve made it yourself, it will contain higher quality ingredients. This will be more attractive to the ravenous mold fungi.

Mold fungus doesn’t need sunlight at all, unlike plants that need light to manage the process of taking carbon dioxide from the atmosphere and fixing it as a hydrocarbon molecule that builds the structure of the plant.

Mold fungus can grow in total darkness. This is why you will see it grow on foods that are hidden away in cupboards and fridges.

Bread from a store that has been commercially made may have added chemical preservatives that are included to inhibit mold growth. One of these preservatives is calcium propionate.

What is calcium propionate?

Calcium propionate is an additive that commercial bakers use to preserve baked food products including bread. There are other additives that are used with this, these being propionic acid and sodium propionate. Some people worry when food additives are mentioned. If you are concerned then baking your own bread may be an option.

Calcium propionate, apparently, occurs naturally in butter and some cheeses. So there shouldn’t be too much to worry about. There have been extensive laboratory trials where calcium propionate and similar compounds, have been fed to rats over a long period. There have been no signs of any adverse effects. The conclusion is that these compounds are non-toxic and are safe to use in commercial food production.

Can you put moldy food in worm compost?

Yes you can. Worms can’t eat fresh food waste because they don’t have the teeth to be able to bite into it. The food-waste needs to be rotten and soft before they can do anything with it. When mold appears on food this is the first stage of the rotting process and the worms are able to feed on the actual mold that grows out from the food. While they are feeding on this the mold is breaking down the main parts of the food so that worms can, later, move in and digest this. The worms rely on mold to eat and to start the decomposition of food waste, for them it’s an ideal arrangement.

You can also put yeast in with the compost , if the need arises.


Find out about composting tea bags.

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