Is there anything I can add to homemade bread to preserve it?

Rather than adding a preservative, slice whatever bread you can't eat within one or two days (or whatever period it is before your bread goes 'off') and freeze it wrapped in heavy-duty aluminum foil. Whenever you'd like some of that bread, either thaw it in advance or warm in a toaster or toaster oven before eating.

Honey is considered a natural preservative. Try adding 2 Tbsp of honey, or replacing the sugar in your recipe with honey.

Do a google search for 'honey natural preservative' and you'll find lots of references.

One commercial bread company has switched preservatives... They use vinegar (I suspect ordinary white vinegar).

Maybe you could give a little bit of vinegar a go and see how that works? You can still smell it if you sniff and sandwiches do have a faint vinegar flavour, but it seems to work well enough for the company and it apparently hasn't sabotaged the product line...

Then again, it /is/ commercial bread...

Vitamin C (ascorbic acid) is a natural preservative. A little also helps the yeast grow (you will find it in many commercial dough enhancers). When I make bread I use Fruit Fresh, a powdered vitamin C with some sugar used to preserve fruit in canning and freezing. I use about 1/4 teaspoon per loaf. I don't know if that is enough to provide additional preservative power, but it is worth a try as it has no downside. Of course you can just get some vitamin c tablets and crush them but it will take some experimentation to figure out how much to add.

You can also use citric acid, I use about a 1/2 tsp of citric acid. It does not do anything for the taste it just perserves. Also, push your dough down and let it rise more than once, I push mine down after the first rise then after the second then on the third I put it in my bread pan and let it rise again but this time in the oven, then after it rises I turn on the oven. It also makes for a lighter bread, more wholes helps it breath better when stored.

Hope it helps.

Try a little fresh lemon juice, along with the suggested honey from this answer.

I have read bread labels that list preservatives; one was calcium propionate and sorbic acid found in Thomas English Muffins. You can look at your own bakery's labels and see if you can obtain the preservative from the baker, grocer, or drugstore.

I bake sourdough bread and if I put in clean sealed plastic bags it molds in 3-4 days. I finally gave up storing it in the bread box. I freeze the extra loaves when I bake. To keep the sourdough from going bad I now keep it in the fridge. I keep it in sealed plastic bags and add a couple of saltine crackers as a moisture absorbent. Keeps for days.

Although they will materially change the profile of the bread you are baking, dried fruits will do a lot to keep bread from molding, especially raisins. Cinnamon will also do this, but will reduce the activity of the yeast in the rising bread as well.

A dear friend of mine is from Greece, and he once told me a story that before WWII, no one in Greece really ate cinnamon raisin bread. But after the war, huge amounts of it was flown in from the USA to feed the hungry population, chosen because it was known to keep for long periods of time. Apparently, now it is a common thing to eat there.

First use 50% white Flour and 50% dark flour. This will help allready to make it last at least a couple of days longer then plain white flour. Also make sure you use Type 00 flour. This also is better to use and last longer. Now it can stay at least a week in very good eatable condition. Using olive oil in stead of butter, and changing sugar into honey, will make sure you can dry store this bread at for 1,5 week before it goed bad.

The big problem is touching the bread with your fingers after it is baked. Your finger will put mold spores on your bread.

I have made bread that will last 3 weeks in my tropical climate by the following procedure:

1. Add 1 gram of calcium propionate to one kilo of flour. Your bread might rise a little slower but you can not taste it.
2. When the bread is cooled down to room temperature after baking, heat the oven to 100-120 degrees C. Place the bread back in the oven for 5-6 min.
3. When removing from the oven, don't touch the bread with your hands. Use plastic gloves or an unused plastic bag.
4. Wrap the bread in cling foil so it is fully covered and untouched.
5. When you use the bread, cut it through the wrap and use additional foil to cover the cut.

The best way I've found to keep my homemade bread fresh is to refrigerate it. After it's cooled to room temp I put it in a plastic bread bag and refrigerate. I make 1/2 whole wheat, 1/2 white flour bread and this is the only thing that keeps it from going moldy on me before I can finish it. My recipe makes a 2 lb. loaf. I put honey in it instead of sugar, but without the refrigeration still turns moldy within 3-4 days. I've tried adding ascorbic acid powder and a couple other things mentioned and they don't work for me. Just refrigerate.

You should try to make is sourdough. Sourdough keeps a lot longer since it is naturally fermented.

When making the bread dough. What you should do is bake what you need and wrap the unbaked dough in plastic wrap and place in the fridge if your going to bake it within a week or two or freeze the dough this way you dont have so much bread going to waste

When making your sugar and yeast liquid, add a couple of tablespoons of white vinegar, this is enough acid to stop bread from growing mould before it is eaten, assuming you make delicious bread in the first place.

Modern 'fast' bread made with store-bought yeast goes stale quickly because the organisms that make it stale can find a home in your fresh bread. Making sourdough using a starter (even if it's not very sour!) means that you have a wide variety of organisms in your bread, so it doesn't go stale mouldy or stale nearly so easily.

I used to make bread with quick-action yeast, and it would go stale in a day or two. I now make it more slowly with my home-grown starter, and it's soft and tasty after a week. Old-fashioned preservative - and much better for you! See How To Make Sourdough Bread Last Longer, Katz explains how it works better in his book "The Art of Fermentation".

Bread pectin. About a teaspoon per cup of flour. You can buy it from Pacific Pectin - a wonderful company. They sell it in smaller quantities than what it says on the website but you have to call them. https://pacificpectin.com/product/pacific-bread-pectin/