Parblanching is a cooking technique that partially cooks food. It is similar to parboiling, but there are some differences. The major difference between the two techniques is that parblanching often involves placing food in cold water, bringing it to a boil, and then simmering it for a few minutes. In contrast, most foods that are parboiled are placed in already boiling water and tend to be cooked for a slightly longer time period.
Most parblanched foods are cooked for their specified time, then immediately immersed in a cold water bath, or sometimes an ice water bath. The purpose of this last step is to arrest the cooking process. Foods that remain hot will continue to cook slightly, which can result in overcooking. You do have to carefully watch time when you’re parblanching and not ignore this final step. Don’t let veggies or meat sit in hot water, and have the cold water bath ready before you start cooking.
You’ll find there are many applications for parblanching foods in simple recipes. If you want to pan fry potatoes on the stovetop for instance, and would like to cut down on your cooking time, parblanching them for a few minutes first will mean the frying process will take less time, and you won’t end up with potatoes that are burned on the outside but still have uncooked interiors. Many recipes for canning vegetables recommend a parblanching process, or you can use simple blanching, usually an even shorter cooking process to slightly cook vegetables you’d like to serve as crudités. Blanching tends to preserve color and crunch but also makes veggies like asparagus or broccoli a little easier to digest.
Another application of parblanching is to remove excess salt from certain meats, or to remove blood from meats. If you parblanch a ham steak or anchovies for a few minutes, you’ll remove some of the salt, which can create a more mild taste and remove excess saltiness. Meats may be parblanched if you’re planning to stir-fry meats and veggies together, and certain types of meat benefit from slight cooking and the “shocking” process of water and ice baths. This is especially true with soft meats like brain and sweetbread, which can become a little firmer through this process.
There are a number of recipes that require pre-cooking of fruits or vegetables so that all foods get done at the same time. Strawberry rhubarb pie recipes may recommend parblanching rhubarb. This helps soften the rhubarb so that you don’t have to overcook the strawberries in order to get fully cooked rhubarb.