When buying barley grass powder, look for these six things:
1) Organic
2) Juiced (some companies just chop up the grass, you want the grass to be juiced so it's easier to digest)
3) Freeze-Dried: Heat kills the enyzmes. Make sure the barley juice is cold dried under 107 F.
4) 100% Pure Barley Grass - Some companies add fillers like brown rice which dilutes the product, meaning more profit for them, less good green barley for you.
5) Cold Grown - Barley grass grown in the cold has deeper roots which equal more nutrient up take.
6) Harvest young. Young barley plants have more nutrient density.