Effect of sprouting on physicochemical, antioxidant and flavonoid profile of onion varieties

This study investigated the impact of sprouting in four Indian onion varieties (Punjab White, Punjab Naroya, PRO-6 and Commercial). Results showed significant (P < 0.05) increase in protein, crude fibre, ascorbic acid content, total phenol content, total flavonoid content, antioxidant activity, anthocyanin content and significant (P < 0.05) decrease in total carbohydrate, energy value and hardness due to sprouting in all the four varieties. HPLC analysis revealed irregular pattern of increase and decrease in flavonoid components. There was no particular trend observed within analysed flavonols due to sprouting in all the four varieties except with the maximum increase in quercetin (219.3-287.4 mg kg(-1)), kaempferol (13.8-17 mg kg(-1)), myricetin (34.6-40.9 mg kg(-1)), quercetin-3'-glucoside (2.9-4.1 mg kg(-1)) and quercetin-4'-glucoside (83-87.1 mg kg(-1)) in case of PRO-6 variety only. The present research work implied sprouting to be beneficial in onion as nutritional and functional potential of all the four onion varieties was improved by sprouting.