This is a bit complicated! Sú on its own means juice. It is also an old-fashioned word for red berries in general, and it is still used today in combination with other words to give the names for two varieties of berry: sú talún (strawberry, literally "ground berry"), sú craobh (raspberry, literally "branch berry"). Strawberry juice is sú sútha talún ("juice of strawberries").
Yes,if you translate it exactly. Its kind of like how the French word for "potato" is literally translated to "apple of the earth" ("pomme de terre"). The French don't actually believe a potato is an apple that grows in the ground (to my knowledge) and the same I'm sure goes for the Irish :)