Does Refrigeration Really Ruin Bread?

sourbread.jpg
Photograph: J. Kenji Lopez-Alt

Does refrigeration really ruin bread?

"I can never decide how to store my bread. I've been told that refrigeration is not a good idea. Is that true? What's the best way to make bread last?"

Ah bread, ye short-lived staff of life. If it weren't for how quickly bread goes stale, I, for one, would eat a lot more of it. But purchasing a big, beautiful loaf, then watching it turn to stone before I'm even halfway through it, is more than my carbohydrate-loving eyes can bear. Not to get all biblical here, but if Moses was able to get water from a stone, surely we should be able to get a few extra days from our loaves before they require a similar level of divine intervention. And wouldn't the refrigerator—the magical modern box of prolonged freshness, with fancy models miraculously dispensing water from their rock-hard doors—be the logical place to do it?

Actually, no. The refrigerator really is bad for bread, though the full story is a little more complicated than just that. To get to the bottom of it, I decided to do a quick little experiment that, sadly, required harming quite a few squishy young loaves.

Staling Science

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Photograph: Max Falkowitz

Before I get to my tests, it helps to understand a little bit about what actually happens when bread goes stale.

To the casual observer, the staling of bread seems like a cut-and-dried case of a loaf that's cut and dried out. But moisture loss is only a part of what causes bread to go stale. The other part? The retrogradation and recrystallization of starch.

Say what?Yeah, I had to read it a few times too when I first consultedHarold McGeeon the subject. Here's what that basically means:

Wheat flour, the primary ingredient (along with water and yeast) of bread dough, is packed full of granules of starch. That starch, in its natural state, is largely in crystalline form, meaning the starch molecules are arranged in a defined geometric structure. Once mixed with water to form a dough and baked in the oven at high temperatures, the crystalline structure of the starch breaks down as the starch absorbs water and becomes increasingly amorphous (meaning the starch molecules have no clearly defined structure).

As the bread cools, however, those starches begin to slowly regroup into a more ordered, crystalline structure again, and it's this gradual return ("retrogradation") to the crystal state ("recrystallization") that causes bread to harden and grow stale. This process is so central to staling, in fact, that even bread that has been hermetically sealed to prevent all moisture loss will still harden and turn stale.

The reason a refrigerator is bad for bread: When bread is stored in a cold (but above freezing) environment, this recrystallization, and therefore staling, happens much faster than at warmer temperatures. Freezing, however, dramatically slows the process down.

So that's the science in a nutshell. What does it mean on a practical level? Let's proceed to my test.

The Test

sourbread.jpg
Photograph: J. Kenji Lopez-Alt

To test various ways of storing bread, I went to a local bakery and purchased four white baguette loaves, all from the same batch that had been freshly baked a few hours earlier. I then cut the baguettes into smaller sections, weighing each one to make sure they were all the same weight, and discarding the ends so that each section had exposed crumb on both sides.

我把面包分成三组:房间temperature, refrigerator, and freezer. For each group I tested several wrapping methods: unwrapped, enclosed in a paper bag, wrapped thoroughly in plastic, and wrapped thoroughly in foil.

As a bonus "breadbox" test, I placed two pieces of bread in my microwave, one unwrapped and one in paper. I don't actually own a breadbox and have no plans to buy one, but I figured a microwave might be a decent stand-in for a breadbox's small, enclosed storage space. (I skipped plastic- and foil-wrapped samples in the microwave since such tight wrapping supersedes any humidity-retaining benefits a breadbox might offer.)

I checked my samples a day later and found the following:

  • All unwrapped bread samples suffered, with the "breadbox", room temperature, and refrigerator samples completely stale; once defrosted, the unwrapped freezer sample showed very mild signs of hardening/drying. Clearly, allowing unchecked moisture loss is the quickest way to make bread go fully stale.
  • The paper bag did very little to prevent drying of the bread: room temperature, "breadbox", and refrigerator samples were all very hard, though surprisingly in this test the refrigerator sample was not quite as stale as the others (this was the one result that diverged from my expectations, but in any case none of the paper bag samples were good so I still wouldn't recommend it). The paper-bag freezer sample fared about as well as the unwrapped one.
  • The plastic- and foil-wrapped room-temperature samples were about the same, showing slight firming but still retaining a good degree of give and tenderness throughout.
  • The plastic- and foil-wrapped refrigerator samples, while still retaining some give and tenderness, were significantly more firm than the room temperature versions; this remained true even after they had warmed to room temperature.
  • The plastic- and foil-wrapped freezer samples, once defrosted to room temperature, had retained more of their original fresh-baked softness than any of the other samples.

Reheating

根据我上面的结果,我们清楚的是the refrigerator is just a plain-old bad idea for bread. But I wasn't done yet: What about reheating the bread?

I set my oven to 350°F and toasted all the samples simultaneously on a baking sheet. Hands-down, the best reheated bread came from the plastic- and foil-wrapped freezer samples, almost indistinguishable from its fresh self a day earlier.

But what's interesting is that the wrapped room-temperature and refrigerator samples, which had staled at remarkably different rates, were indistinguishable from each other once reheated. As it turns out, even after bread has been baked and cooled, after the starch has recrystallized to create a stale texture, you can actually reverse that crystallization process through reheating and return the stale bread to a state much closer to its original glory (assuming you didn't allow much moisture loss during storage). Not as good as frozen, but still much improved.

Conclusion

So here's my practical advice. In lieu of acts of god and any other kind of divine intervention, the best way to store bread is well wrapped in plastic and/or foil in the freezer, whether sliced or not, then reheated in the oven. If you don't want to deal with reheating the bread, wrap it well in plastic and/or foil and keep it at room temperature; it won't be as good the next day, and it will only get worse from there, but you should be able to eke some extra life out of your bread before it's no longer enjoyable. And if you do let it sit for too long (or if you make the mistake of refrigerating your bread), pop it in the oven and you should be able to reverse a fair amount of the staling, assuming you had it wrapped well enough to prevent drying. Now that reallyissqueezing water from a stone.