8. Rhubarb Leaves
Rhubarb serves many purposes in the food and beverage industry. Its stalks, usually from a variety of the plant known as garden rhubarb, are widely used in food preparations and also to flavour syrups, spirits and cocktails. Rhubarb roots, usually from the Chinese rhubarb variety, are used mainly as a flavouring agent in bitter liqueurs such as Zucca and Aperol.
However, its leaves are not suitable for consumption as they contain high levels of oxalic acid, a compound which in our body binds with calcium and increases the chances of kidney stones and also cause nausea. In most places where you can buy rhubarb, they will not sell rhubarb leaves – mainly just the stems – but knowing about their toxicity might come in handy if you decide to grow your own plant at home or at the bar.