Whether you bake homemade bread to save money, because you like the taste or just to avoid the artificial preservatives in store-bought bread, you have probably found that despite its advantages, homemade bread has an annoying way of going moldy faster than store-bought bread, because of the lack of those preservatives. However, you can use some natural, homemade bread preservatives to make your bread keep longer.
A 2008 study by Spanish researchers found that cinnamon oil added to wax paper packaging inhibited mold growth on bread by several days. Cinnamon oil may also inhibit the growth of yeast, so if you want to use cinnamon as a bread preservative, be sure not to add it before letting the dough rise. Mix it into the dough in the last step, or add cinnamon powder or baste the bread with cinnamon oil just before baking.
Ascorbic acid, or vitamin C, is a great additive to bread for several reasons. Not only is it an essential vitamin, it also improves the rising action of yeast when added to the dough in the initial steps, and it functions as a preservative after bread is cooked. If you can't find ascorbic acid, which is sold in powdered form in many health food stores, you can substitute a crushed vitamin C tablet.
Garlic is another spice with preservative properties. A 2000 study in Denmark found garlic oil, along with clove and cinnamon oil, to be among the most effective bread preservatives. For a stronger preservative effect, use fresh garlic or garlic oil instead of powdered garlic.
If you don't like garlic or cinnamon, don't despair; those are not your only options. Many spices function as preservatives; in fact, that's one reason for their popularity in the history of cooking. Ginger, clove oil and mustard oil are among the other flavoring agents that will also work as homemade bread preservatives.
Pure honey will never mold, as its sugar concentration is too high to allow enough water for mold to grow. Sadly, the same is not true of bread made with honey, since it must be mixed with water in the dough. However, honey will still keep bread from going stale as fast, because it contains the simple sugars fructose and glucose instead of the sucrose that is used as common table sugar, and these simple sugars attract more water molecules.
In addition to preservatives that you add to your bread to keep it fresh, you can use storage techniques that help it last longer. Keep it in a cool place (but not the refrigerator, or it will dry out). Wash your hands well before touching the loaf, and try not to touch any part of the bread but the piece you are going to eat immediately. Avoid letting it touch your counter or other foods in your kitchen. Keep it in a sealed, airtight bag.