Why Your Frozen Brussels Sprouts Are Brown On The Inside

If you've cut into recently thawed frozen Brussels sprouts and noticed that they're brown on the inside, it's probably an indication of improper freezing procedures. The step that will prevent brown discoloration in the freezer is blanching. This involves boiling the Brussels sprouts for a quick stint before quickly draining them and throwing them into ice water to stop them from cooking further.

Blanching Brussels sprouts serves many preservative purposes. The first, and most important, is that the boiling water temperature will effectively kill any bacteria they might harbor on the surface. Boiling also acts to lock in the veggies' color, texture, and flavor because it halts the enzyme activity that leads to discoloration and the breakdown of texture and taste. It's this very enzyme activity that can cause brown hues on the inside of frozen Brussels sprouts that haven't been blanched. So, if you see brown inside your Brussels, you can also expect them to have a degraded soft or mushy texture and a bland, flavorless profile.

Brown coloring doesn't necessarily indicate that frozen Brussels aren't safe to eat, however. Browning or dulling of color in conjunction with shriveled leaves are more an indicator of freezer burn, not of rotting or bacterial growth. While freezer burn will not make you sick, freezer-burned Brussels will have lost many of the desired qualities of their former freshness, so they're probably not worth eating.

When freezing Brussels sprouts, you want to ensure that they are at their freshest to lock in the best flavor, color, and texture when blanching them. You can prep the Brussels the same way you would for steaming or roasting them, discarding stray and yellow leaves and cutting out the hard core at the bottom of the sprout. You can then blanch them whole, which is the most common way for store-bought frozen Brussels like these from Birds Eye to be sold. That said, you can also halve or quarter the Brussels sprouts before blanching them to make them easier to use when defrosted. Bring a pan of water to a boil before adding the Brussels sprouts, throwing them in for just 2 to 3 minutes before draining and shocking them in ice water.

Then, to freeze them quickly while minimizing water saturation, spread the blanched Brussels sprouts over a baking sheet before placing them into the freezer for a few hours. Once frozen, you can transfer them to a freezer-safe container like a sealable plastic bag or an airtight tub. You can use frozen and halved Brussels sprouts instead of fresh in many of our recipes without defrosting, like these easy balsamic roasted Brussels sprouts or these garlic butter Brussels sprouts. The only tweak you might want to make is increasing the cooking temperatures to impart a crispy char.