Effect of fermentation on chemical and bioactive properties and phenolic profiles of caper (Capparis ovata Desf. var. ovata) flower buds in three different sizes

Abstract

In this study, caper buds collected in Konya were separated according to their size three different sizes (x ≤ 8 mm, 8 < x ≤ 13 mm, x > 13 mm). Caper buds were fermented at 8% and 12% brine concentration. Antioxidant activity, total phenol, phenolic components, carotenoid, flavonoid, salt, titration acidity and pH analyzes were performed on the 0., 5., 10., 30. and 45. days of the fermentation applied of the caper buds. The pH values of 12% brine concentration medium size caper buds ranged from 4.56 (5th day) to 5.01 (0th day). The titration acidity of small size caper buds with 8% brine concentration ranged from 0.02% (0th day) to 0.21% (30th day). The salt values of small size caper buds with 12% brine concentration varied between 6.22% (30th day) and 12.09% (0th day). In terms of total phenol content, small size caper buds fermented for 10 days and 8% brine concentration had the highest value of 345.31 mg/100 g. The flavonoid content of caper buds was determined as 2633.75 mg/100 g in small sized samples subjected to fermentation for 5 days at the highest 8% brine concentration. The carotenoid values of small size caper buds with 8% brine concentration varied between 0.52 mg/g (30th day) and 2.40 mg/g (0th day) during the fermentation period. It has been determined that the antioxidant activity values increase as fermentation progresses. The phenolic compounds with the highest percentage were found to be gallic acid, 3,4-dihydroxybenzoic acid, (+)-catechin, 1,2-dihydroxybenzene and syringic acid. The gallic acid values of medium sized caper buds with 8% brine concentration vary between 21.07 mg/kg (0th day) and 70.27 mg/kg (45th day) during fermentation. The 3,4-dihydroxybenzoic acid values of small size caper buds with 8% brine concentration were determined between 4.08 mg/kg (0th day) and 37.50 mg/kg (30th day) during fermentation. Dill extract with 0.3% concentration and coriander extract with 0.1% concentration were the most preferred ones in terms of taste.