Loading…
Food · Grains & Legumes · Grains
food source · 2
Quinoa is one of the very few plant foods with enough of all nine essential amino acids, lysine especially, which is exactly what grains lack most. But it does not have much protein: cooked quinoa has about 4.4 g per 100 g.
Mechanism · It has what grains lack
Grains such as rice and wheat mostly fall short on lysine. Quinoa has enough of all nine essential amino acids, lysine especially, so it is complete on its own and does not need pairing the way rice and beans do. It is not a grass grain but the seed of a plant in the amaranth family, a close relative of spinach and beets, which is why its amino acid pattern is unlike that of wheat or rice.
Numbers · Strong on balance, not on amount
Complete protein means no weak spot, not more protein than meat: cooked quinoa has about 4.4 g of protein per 100 g against about 2.7 g in white rice, far less than the same weight of tofu or egg. For vegetarians, making quinoa a staple eases the amino acid balance, but the total still has to come from beans and soy foods. The bitter saponins coating the seed should be rinsed off before cooking; what washes away is the bitterness, not the protein.
Quinoa is high in magnesium for a staple food, clearly above white rice and above brown rice too. Magnesium has to bind ATP before the body's energy currency can be spent.
Mechanism · A staple unusually rich in magnesium
ATP has to bind magnesium before enzymes recognize it, so magnesium is the ion that lets the energy currency be spent. Polishing white rice grinds away the bran and the magnesium with it; quinoa is eaten as the whole seed without that kind of milling, so the magnesium stays in the seed you cook.
In practice · Phytate and rinsing
Quinoa has clearly more magnesium than white rice, and more than brown rice too. Its phytate still locks up part of its minerals; rinsing it well or soaking it before cooking removes some of the phytate and washes off the bitter saponins at the same time.