Contents of dry matter, soluble sol­ids, vitamin C and phenolic compounds in the pulp and peel of different cultivars of pear fruits

Abstract

The aim of this work was to investigate and compare the amounts of biologically active compounds, dry matter and soluble solids in pulp and peels of four pear cultivars (‘Ksena’, ‘Beloruskaja pozdniaja’, ‘Alna’ and ‘Aleksandr Lucas’). The research was carried out at Vytautas Magnus University Agriculture Academy (Lithuania) in 2020. Four pear cultivars (‘Ksena’, ‘Beloruskaja pozdniaja’, ‘Alna’ and ‘Aleksandr Lucas’) were cultivated at a farm in the Joniškis District of Lithuania. Pears were grown following traditional pear production technology. The amounts of dry matter, soluble solids, vitamin C and fiber were determined using the standard method. The total content of phenolic compounds was determined using a Folin-Ciocalteu reagent with a UV/VIS spectrophotometer. The research results showed that significantly the highest amounts of soluble solids were found in the ‘Alna’ pear fruit pulp (14.25% f. w.). The ‘Alna’ peel sample had significantly the highest amount of total phenolic compounds (1290.99 mg 100 g^–1 d. w.). The highest content of dry matter was found in the ‘Aleksandr Lucas’ pear fruit peel (24.67%). The ‘Aleksandr Lucas’ and ‘Beloruskaja pozdniaja’ pear fruit peel contained significantly the highest amounts of vitamin C (2.70 and 2.63 mg 100 g^–1 f. w., respectively). The highest content of fiber was found in the ‘Ksena’ fruit peel (36.12% d. w.). The investigated pear peel sample had significantly higher amounts of dry matter, vitamin C, total phenolic compounds and fiber than the pulp. However, the pulp contains the highest contents of soluble solids.