Keep the bread out of the fridge

Until about a month ago, I included this in my notes to my customers:

But here's how you should be storing your bread and the science behind why refrigeration is bad.

It turns out that refrigerating bread makes it stale. Although I had the right mindset in the sense that refrigeration slows down the development of mold, cold temperatures recrystallize the bread's starches, making the bread lose moisture. 

How does starch recrystallization cause this loss of moisture? Two blog posts ago, I wrote about the science behind tangzhong. This roux is the product of gelatinization, a process that also breaks the bonds of the starches and destabilizes the original crystalline structures of flour, making the starch gooey fluffy bread. Crystalline structures are organized, but since the starches swell to absorb water, water gets in the way of having an organized crystalline structure.

Cold temperatures make the starches want to revert themselves to the ordered, crystalline structure - hence why recrystallization is also called retrogradation. To reorganize themselves, they must kick out the water, and so the bread becomes stale.

If you want to preserve your bread for longer, slice it up and then put it in the freezer. Yes, on the extreme side of cold temperatures, freezing temperatures stop retrogradation, so the moisture that the bread was frozen with stays until it is thawed.