Do blueberries still provide strong antioxidant support after they have been frozen?

Yes, even after blueberries have been frozen, they can provide you with excellent antioxidant support. It's important, of course, for your blueberries to be high quality before they are frozen, and for this reason, I recommend organically grown blueberries that are firm and lively colored when purchased. Avoid blueberries that are dull in color or appear soft and watery. If purchased in a container, I recommend that you gently shake it to make sure that the blueberries are firm enough to move freely and independently.

I encourage you to pay special attention to the color of your blueberries because a large part of that color comes from the anthocyanins (antioxidant phytonutrients) in the berries. There's good research showing very little loss of anthocyanins after freezing of healthy, ripe berries so you'll hardly be losing any of these unique antioxidants if you properly freeze high-quality fresh berries.

For other antioxidant nutrients, the loss due to freezing varies from about 10-40%. You'll
lose less than 20% of your berries' vitamin E, lutein, zeaxanthin, and beta-carotene from freezing, and that's plenty of reason to take advantage of freezing as a convenient way to enjoy blueberries even when they are out-of-season. The amount of vitamin C lost during freezing can vary widely and can be substantial, but I still recommend that you treat freezing as a very acceptable step when it comes to blueberries. While fresh blueberries still rank highest on my recommendation list, all of the trade-offs involved with frozen blueberries seem worthwhile to me. I would consider that you'd still be following the Healthiest Way of Eating if you go the frozen route when fresh berries are not available.

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