Utilization of irradiated onion scales as a potential source of bioactive natural food colour

In the food industry there has been an increasing trend towards the replacement of synthetic food colours by natural colours because of safety and health benefits. Increasing market for natural colours has led to a search for new and economical sources. Onion scales are rich source of anthocyanins which could be tapped as a potential food colorant. India is the second largest onion (Allium cepa L.) growing country in the world and Maharashtra ranks first amongst the states in onion production. Large quantities of dry onion scales are generated and they are usually discarded before onions are processed for consumption. Onion scales (OS) are prone to fungal contamination. The objective of this study was to evaluate the potential of using irradiated onion scales as a potential source of natural food colour. The extraction time, temperature and solvent were standardized for obtaining OS extract having maximum bioactivity and highest anthocyanin content. OS can be used as a source of natural food colour due to its high anthocyanin content and excellent bioactive properties