Rhubarb is a colourful and flavourful, yet under-appreciated, vegetable that is at its peak this time of year. Though not common in most people’s diets, this tart plant may offer cancer-preventive properties.
The edible part of the rhubarb plant — the stalk — contains anthocyanins, which yield its bright red colour. Anthocyanins are a type of flavonoid found in foods such as berries, red onions, black beans, red grapes and black plums. They act as antioxidants in test tube studies, but in the human body, their protection seems more likely to come from their role in cancer-preventive cell signalling. Anthocyanins have demonstrated protective effects on blood vessels and blood pressure, and recent research suggests that anthocyanins may offer anti-cancer benefits, too.
Rhubarb is also a great source of vitamin K1, which is important for blood clotting and bone health. A half cup of cooked rhubarb provides more than one-third of the recommended dietary intake of vitamin K1, along with two grams of fibre (which helps prevent colorectal cancer), some calcium and vitamin C.
Rhubarb originated in China, where its roots were first harvested and dried for medicinal use. It is now grown either outdoors or in greenhouses in temperate climates throughout northeast Asia, North America and northern Europe. Stalks may be harvested starting in their second growing season. The stalks range in colour from green to red and have large, green leaves.
If you grow your own rhubarb, be careful to avoid the leaves, as their high levels of oxalic acid make them poisonous. At lower concentrations, this compound isn’t harmful for most people. But the amount in rhubarb leaves can cause severe vomiting and at very high levels, it could be fatal.
Rhubarb is commonly eaten in sweet desserts — most famously known for combining with strawberries in pie — to counterbalance its strong tartness, but don’t be afraid to get creative. Try cooking down chopped rhubarb with a little lemon juice and sugar into a compote to top plain yoghurt, oatmeal or goat cheese. Or, bake it into whole-grain muffins in place of another fruit and add a little ginger or cinnamon. For a savoury option, chop and add rhubarb to diced red onion, a splash of balsamic vinegar and a little mustard to create a zesty sauce for your favourite fish.
For a refreshing drink without added sugar, try this Rhubarb Orange Refresher
Ingredients:
3 cups fresh rhubarb, cut crosswise in 1/2-inch slices, about 3/4 lb.
4 cups cold water
1 cup strawberries, sliced
1 cup orange juice
4 mint sprigs, for garnish
Directions
In a large, stainless steel or other non-reactive saucepan, combine rhubarb and water. Cover and bring to boil over medium-high heat. Reduce heat and simmer 15 minutes. Set covered pot aside to steep for 10 minutes.
Set large strainer over bowl. Pour contents of pot into strainer and drain liquid into bowl. Using back of wooden spoon, press very lightly on rhubarb, just to extract liquid that drains easily. Pressing too firmly will make infusion cloudy. Discard pulp. Pour liquid, about 4 cups, into jar or other container, preferably glass, and let sit until room temperature, then cover and refrigerate for up to 2 days.
To serve, measure 3 cups rhubarb infusion. Pour 1/2 cup into pitcher, add strawberries, and muddle until combined. Pour in remaining rhubarb infusion and orange juice. Divide among 4 ice-filled, tall glasses. Garnish each glass with mint sprig, if using. For single serving, in a glass, combine 1/4 cup rhubarb infusion with 2 strawberries, and then add remaining 1/2 cup infusion, 1/4 cup orange juice and ice.
Makes 8 servings
Per Serving:
30 calories, 0 g total fat, 0 g saturated fat, 7 g carbohydrate, 1 g dietary fibre, 1 g protein, 0 mg sodium