In a 4 qt. pot combine water, white wine vinegar, olive oil, salt, black pepper, and lemon juice.
Clean artichokes by peeling off petals until interior tender green pedals are exposed. Trim down the sides and the stem peeling away a thin layer. Trim the top of the petal end and stem end, split in two lengthy wise. With a small spoon, scoop out the furry choke from each of the artichoke halves. Place trimmed artichoke hearts in pot.
Cover the pot and bring to a simmer over medium-high heat; reduce the heat to medium low to maintain a gentle simmer. Poach the artichokes for 8-10 minutes, or until the tip of a paring knife slides in easily at the thickest point.
Remove the artichoke hearts and cool on a sheet pan.
Reserve cooking liquid for blanching broccoli.