Cauliflower is an essential ingredient in cuisines from Africa to Asia, adding texture to stir fries and complementing savory dips. It is also a nutritional powerhouse, rich in potassium and high in vitamins A and C. But cauliflower can sometimes taste bitter, even to people who typically enjoy it. Taste cauliflower before combining it with other ingredients to avoid ruining an entire dish if its bitterness can't be remedied.
Cauliflower exposed to too much sun while it grows can develop a bitter flavor. Protect growing heads from direct rays using a process called "blanching." To blanch a cauliflower plant, wait until the head reaches 2 to 3 inches in diameter, then wrap the adjoining leaves gently around them. Tie the leaves to keep them in place, leaving enough room for the heads to grow. Cauliflower can also grow bitter if you wait too long to harvest it, so pick it soon once it reaches 6 inches in diameter.
Cauliflower that is overcooked can grow bitter, so err on the side of under-doneness. Unlike green vegetables such as broccoli, which grow more vibrant in color as they cook and then lose color as they overcook, cauliflower stays the same shade of white throughout the cooking process. To test for doneness, prick the cauliflower with a fork several minutes before your recipe's prescribed cooking time or, if you aren't using a recipe, after four or five minutes. If the florettes are fork tender but still somewhat firm, the cauliflower is fully cooked.
Some varieties of cauliflower, such as the brilliant purple heads, tend to have less bitterness than the white varieties found at most supermarkets. If you are especially sensitive to bitterness, choose purple over white cauliflower whenever you have the opportunity. Purple cauliflower is an heirloom variety not always widely available. However, you can often find it at farmers' markets and supermarkets that feature local and unusual fruits and vegetables.
Individual tastes vary, and there is an evolutionary component to a sensitivity to bitter flavors such as cauliflower. Supertasters are individuals whose taste receptors are characterized by elevated sensitivity to potentially bitter flavors in foods such as cauliflower and tea. If you are genetically predisposed to find cauliflower bitter, you can choose less bitter varieties such as purple heads and avoid overcooking them. Use a bit of salt to block cauliflower's bitterness, or a fat such as olive oil to mellow its flavor.