Which types of frozen vegetables are an acceptable substitute for fresh?
We use a lot of frozen vegetables in the test kitchen, but not all frozen vegetables are created equal. Vegetables with a lower moisture content generally freeze well, while their high-moisture counterparts turn mushy when frozen. And not all brands of frozen vegetables are created equal. We've had the best luck with the 365 Everyday Value brand from Whole Foods supermarkets, which consistently taste fresh and don't exhibit freezer burn. Here are the frozen vegetables we like best.
We prefer frozen peas to fresh—they are more convenient (you don't have to shell them) and reliably sweeter. This is because the sugars in peas convert to starch very quickly after they're picked; peas that are to be frozen are blanched almost immediately after picking, which halts the conversion of sugar into starch, keeping frozen peas sweet.
Corn (Out of Season)
During the summer months, freshly picked corn is clearly superior to frozen. But for the rest of the year, we prefer frozen corn kernels (not frozen corn on the cob, which generally has a poor texture) because they are consistently sweet.
Because pearl onions are generally used in long-cooked recipes, such as beef stew, the compromised texture of the frozen variety doesn't much matter. Frozen pearl onions come peeled and therefore require none of the laborious preparation of fresh.
In the test kitchen, we rarely use fresh lima beans, which are hard to find, and we never use the canned variety, which are too mushy. Frozen lima beans have good texture and flavor, and they hold up well in salads, soups, and side dishes.
While frozen spinach is clearly not suitable for a salad, it is a good option for cooked dishes. Make sure to thaw and thoroughly dry frozen spinach before cooking.
Frozen broccoli, cauliflower, carrots, and green beans are acceptable options for soups, stews, and long-cooked dishes, where their less-than-crisp texture isn't a factor. But we always prefer the crunchy texture of fresh when these vegetables are the main component of the dish.
High-moisture vegetables like bell peppers, snow peas, snap peas, asparagus, and mushrooms do not freeze well, and you should avoid them both on their own and in frozen vegetable medleys.