How does stale bread taste

Once gelatinization has occurred it is irreversible. Freshly gelatinized starch is delicious, think of a freshly baked bread, freshly cooked rice or a just baked potato. However, over time, the starch changes again, which causes your bread to turn stale, the potato to become chewy and dry and the rice to be firmer. During the staling of bread, starch again changes it configuration. Whereas it cannot go back into those original granules, the molecules can organize themselves in a slightly more structured way within the bread.

The amylose and amylopectin molecules can reorient themselves within the bread and form structures. The starch becomes more ordered and as such more crystalline. This is the main reason of bread turning dry and stale!

Amylose and amylopectin both retrograde slightly differently. The retrogradation of amylose sets in more quickly than that of amylopectin and is less reversible than than of amylopectin as well. Luckily, some of these structures can be reversed by heat, which opens up some ways to revamp your stale bread.

A quick note, as we mentioned above, bread turning stale is just a quality issue, it does not impact the safety of your bread. If you store bread outside of plastic in a non-humid room temperature environment, most breads turn stale, very stale, well before they ever spoil because of the growth of microorganisms. Just about every bread will stale over time, if you leave it enough time.

There are several ways to significantly slow down the process though. First of all, do not store a freshly baked bread in the fridge. Whereas storing bread in the fridge slows down growth of micro organisms, it actually speeds up the starch retrogradation process. In other words, it speeds up staling of bread. A commonly used method to prevent staling is by partially breaking down those complex starch molecules.

You can break up starch molecules using specialized enzymes : amylases. It is also well documented that sourdough breads can be kept several days longer without them turning stale and becoming inedible! It is thought that the bacteria in the sourdough have a similar mode of action as the enzymes discussed above.

They break up some of the starch and even protein molecules, decreasing the extent of staling. Since every type of bacteria is slightly different, different sourdoughs will have a different impact.

Fat can slow down retrogradation by sitting in between all those starch molecules, preventing them from forming that more crystalline structure. Despite all your efforts, your bread might still turn stale. But hope is not yet lost! Bread can go stale if left out at room temperature. Once the bread and the starch make contact with bacteria in the air, the process of the ingredients beginning to slowly decay have already begun to take place. Bread must be kept away from heat and moisture when it is out of the refrigerator.

The variations in temperature will quickly cause bread to begin to go stale, and mold will soon start to form on the bread. Proper storage is essential in making sure that bread does not go stale and is kept fresh tasting, easy to cook with and eat at all times. Keep bread in airtight containers such as a breadbox, unused stove or microwave oven. Whether store-bought or homemade, bread should always be wrapped securely in plastic or aluminum foil so that air is kept away.

Finding a dark location is also beneficial to keeping your bread fresh and reduces the risk of a temperature variation due to sunlight or warm halogen lights. Thanks for reading Scientific American. Create your free account or Sign in to continue. See Subscription Options. Go Paperless with Digital. Get smart. Sign up for our email newsletter. Sign Up. You can perhaps squeak another day of sandwiches out of such a loaf by wrapping it tightly and storing it at room temperature.

Well-wrapped bread freezes beautifully so be sure that you create an airtight seal for any pain destined for the ice box. Wrap it tightly in plastic wrap and then again in foil or freezer paper to protect your precious loaf from the bite of freezer burn.

To defrost, remove the bread from the freezer and allow it to come to room temperature in its wrapping if you unwrap the loaf while it is still cold, condensation will form on its exterior, compromising the texture. But fear — and pitch — not! You can revive bread by restoring its moisture. Bread that is rock hard needs to get a full bath.