Reduced Cooking Time

• For many durable vegetables, a reduction in cooking time is one of the key benefits to blanching. This is one of the techniques used by restaurants to put food on the table efficiently, night after night. Vegetables that are blanched ahead of time can be kept in a refrigerator until they're needed, then cooked quickly to accompany the rest of the meal. French fries are made through a similar process, oil-blanched at low temperature until they're soft and then later cooked quickly at high temperature to crisp and brown the outside.

Reduced Spoilage

• Once they're picked, most vegetables and fruits begin to soften and decay almost immediately. This is largely due to natural enzymes in the foods, designed to help them break down and nourish the soil. That's a good thing in the compost pile, but it isn't as welcome in the freezer. Blanching your fruit or vegetables before freezing them deactivates those enzymes, extending their storage life and minimizing deterioration.

Reduced Volume

• In the case of leafy greens, blanching them before they go into the freezer brings another benefit. In their natural state, greens are bulky, and take up a lot of space. Blanching them causes the air trapped in their cells to escape, giving them a vivid green color. It also makes their cell walls collapse, shrinking the greens to a fraction of their original volume. That makes them much more space-efficient, and more practical to store in your freezer.

Reduced Impact

• Some foods are flavored so strongly that they're unpleasant to eat, usually because of bitterness. Others contain toxins, which must be removed through blanching or cooking and -- in extreme cases -- several changes of water. Blanching escarole, radicchio or dandelion greens moderates their distinctively bitter flavors and makes them suitable for soups or mixed-greens dishes. Nettles are used in a number of age-old recipes, but must first be blanched several times to remove their high levels of oxalic acid. Fiddleheads and bamboo shoots, wild greens from widely different parts of the world, are blanched to remove toxins and speed their final cooking.