One of the few vegetables I always blanch is broccoli. For years I skipped blanching before freezing altogether. As I mention elsewhere on this blog, blanching affects food quality rather than food safety, and I wasn’t really tasting the difference with most vegetables. Besides, I grill corn, onions, eggplant, and most other veg before freezing, which makes a blanch step redundant.
Broccoli, I’ve learned, is a big exception. Frozen raw, it ends up tasting bitter and woody, even when you add cheese and stock to make a soup. I opt to place the chopped stems and florets in a steamer basket instead of plunging them into the boiling water. Hervé This explains in Kitchen Mysteries that hydrogen ions ultimately are responsible for cooked vegetables appearing brown instead of green. Putting vegetables directly into water only increases their contact with hydrogen. Learn to steam-blanch broccoli and make Broccoli Cheese Soup