Why You Should Never Thaw Frozen Green Beans Before Cooking Them

Green beans are an awesome veggie to stash in the freezer to make a quick green bean casserole or a roasted tray of verdant, garlicky goodness. And the best bit? You don't need to defrost them first. In fact, you should never thaw frozen green beans because it makes them lose their characteristic crunch and texture.

Why does this happen? When green beans (or any other variety of vegetable) are frozen, the water inside of them crystallizes, expands, and takes up more space. This puts pressure on the structure of the beans and ruptures their tender surface, creating little fissures. When the beans are left out to thaw, the natural water inside them melts and escapes through these ruptures and softens the surface, leaving them limp and mushy instead of firm and snappable.

As green beans can be cooked from frozen, there's really no need to thaw them first. Simply toss them straight into a bubbling stew, incorporate them in a baked casserole, or coat them in spices and roast them on a sheet pan. Baking your frozen green beans is one of the best techniques because the hot temperature causes all of the excess moisture in them to evaporate away, leaving your veggies full of welcome texture and roasted flavor. If you would still prefer to thaw your green beans, place them in the refrigerator rather than leaving them on the countertop. If you set them out on the worktop, there's a greater risk of bacteria multiplying inside.

The same expansion of water that occurs when green beans are frozen also happens with other types of frozen vegetables, like sliced bell peppers, as well as fruits, such as frozen raspberries and strawberries. You shouldn't thaw frozen berries before baking with them because it releases their juice, leaving the berries squishy and formless. This makes them more likely to bleed into cake batter or scone dough, producing pockets of unwanted moisture that can affect the final texture of the bake.

However, some leafy vegetables, like spinach, are better off thawed depending on how you're planning on using them. For instance, frozen spinach can be added straight into bubbling curries and stews, but if you want to use it as a pizza topping, it should be defrosted and squeezed of excess moisture first to make sure the crust doesn't get soggy. If you really must thaw spinach or green beans, you can do it in the microwave using the defrost function. A quick 30 second zap should be enough to take the chill off your veggies without them releasing all of their moisture. 

Fresh green beans are ideal when making something like a batch of tangy green bean pickles where optimum crunch is essential, but in most cases, the frozen stuff works perfectly well.