Scientists say that onions skin is beneficial for human health.
According to the researchers, the brown skin and external layers are rich in fibre and flavonoids, while the discarded bulbs contain sulphurousBenitezs research group worked with scientists from Cranfield University ( United Kingdom) to carry out laboratory experiments to identify the substances and possible uses of each part of the onion.According to the study, the brown skin could be used as a functional ingredient high in dietary fibre (principally the non-soluble type) and phenolic compounds, such as quercetin and other flavonoids (plant metabolites with medicinal properties). The two outer fleshy layers of the onion also contain fibre and flavonoids.Phenolic compounds, meanwhile, help to prevent coronary disease and have anti-carcinogenic properties. The high levels of these compounds in the dry skin and the outer layers of the bulbs also give them high antioxidant capacity.The study is detailed in the journal Plant Foods for Human Nutrition.