The two ellagitannins, lambertianin C and sanguiin H-6, were
detected in high quantities in the fruits, i.e., in average 38 and
55 mg/100 g FW, respectively. Sanguiin H-6 was the most
abundant ellagitannin in all genotypes. The highest contents of total
ellagitannins were found in ‘Malling Hestia’ (146.5 mg/100 g,
74% sanguiin H-6), and the lowest contents in ‘RU974 07002’
(59.8 mg/100 g, 64% sanguiin H-6). Considerably higher variation
in concentrations of lambertianin C was observed among genotypes
than between harvest seasons. Only low concentrations of
free ellagic acid and its sugar conjugates along with four quercetin
glycosides were found in the fruits. The total concentration of ellagic
acid conjugates (EAC) ranged from 0.6 mg/100 g FW in ‘RU004
03067’ and ‘RU97407002’ to 1.4 mg/100 g FW in ‘Malling Hestia’.
Comparable concentrations have previously been reported In the present study, the total
content of quercetin glycosides ranged from 0.7 mg/100 g FW in
‘Glen Magna’ to 2.4 mg/100 g FW in ‘RU004 04095’. These values
were also in accordance with a previous study In the present study, the most abundant quercetin
glycosides were quercetin-3-glucoside and quercetin-3-glucuronide
with average contents 0.8 and 1.3 mg/100 g FW, respectively
(data not presented). The lowest values of most individual phenolic
compounds were detected in 2010 and the highest in 2011. As in
the present study, seasonal variation in quercetin content among
red raspberry genotypes has also previously been showed