Yield and content of selected nutrient components in some cultivars of onion and shallot bulbs

Abstract

The studies conducted in the years 2012–2013 included the assessment of the yield, dry matter, flavonoids, phenolic acid and L-ascorbic acid content in onion and shallot bulbs. Common onion (cultivars ‘Agostana’,’ Karmen’ and ‘Wolska’) and shallot (cultivars ‘Ambition F₁’, ‘Matador F₁’ and ‘Toto’) were cultivated from seedlings planting. The content of total and reducing sugars, flavonoids (converted into quercetin), as well as phenolic acids (converted into coffeic acid) was determined in fleshy scales, whereas in dry scales only the content of flavonoids and phenolic was determined. Antioxidant activity in the bulbs of the studied cultivars was evaluated by means of the method using DPPH. Among the studied cultivars of onion and shallot the highest yield was found in ‘Wolska’. The bulbs of onion cultivars were bigger as compared to shallot, which resulted in obtaining a decidedly higher yield. The studies presented in this work demonstrated that in onion and shallot the content of particular chemical compounds significantly depend upon the cultivar. Besides, the level of flavonoids and phenolic acid content in dry scales is many times higher than the content of these components in fleshy scales. It resulted on increasing the level of antioxidant activity measured as the percentage of DPPH inhibition.