Biochemical Characterization of Some Plum Cultivars Available on the Romanian Market

Four plum cultivars commonly grown in Romania, ‘Angeleno’, ‘Anna Späth’, ‘Silvia’ and ‘Stanley’, were analyzed with regard to several parameters, including water content, juice pH, phenolic compounds (total and some major classes), carotenoids, ascorbic acid and soluble sugars. Among the four studied cultivars, ‘Silvia’ ranked the highest in terms of total phenolic content (82,345 mg/kg DW), flavonoids (43,171 mg/kg) and anthocyanins (1991 mg/kg). Hydroxybenzoic acids were found to be an important phenolic component; up to 33,971 mg/kg was found in ‘Angeleno’. The hydroxycinnamic acid content was highest in ‘Stanley’, and stilbenes were most prevalent in ‘Anna Späth’. Tannins were found in significant amounts only in fruit peel and were only present in some of the cultivars. Carotenoids were mostly present in the epicarp, with the maximum amount identified in ‘Anna Späth’ (313 mg/kg). The main compounds were β-carotene (of which the highest amount was identified in ‘Silvia’), lutein (with the highest amount found in ‘Silvia’) and lycopene (with the highest amount detected in ‘Stanley’). ‘Silvia’ also contained the highest amounts of ascorbic acid (7895 mg/kg in pulp and 12,229 mg/kg in peel). The highest soluble sugar content was found in the pulp of ‘Stanley’ (142,120 mg/kg), while ‘Anna Späth’ contained the lowest amount of soluble sugar. ‘Stanley’ also had less acidic pulp juice. Among the four cultivars, ‘Silvia’ ranked the highest in most classes of bioactive compounds, including total phenolic compounds, flavonoids, anthocyanins, tannins (peel only), β-carotene, lutein and ascorbic acid.