Raspberry sales in the UK are reported to have grown by 62 per cent in the last two years compared to strawberries at 34 per cent, according to AC Nielsen.
In a new study, published in the journal BioFactors (Vol. 23, pp. 197-205), it is reported that raspberries contain almost 50 per cent more antioxidant activity that strawberries, three times that of kiwis, and ten times the antioxidant activity of tomatoes.
Vitamin C makes up about 20 per cent of the total antioxidant capacity, accounting for up to 30 milligrams per 100 grams of fruit. Anthocyanins, especially cyanidin and pelagonidin glycosides, account for a further 25 per cent.
Interestingly, the biggest contribution to antioxidant capacity is from ellagitannins, a family of compounds almost exclusive to the raspberry, and are reported to have anti-cancer activity.
"It is especially the presence of large amounts of ellagitannins in raspberry, in combination with the more usual anthocyanins and vitamin C, which makes this fruit an attractive subject of study," said lead author Jules Beekwilder, from Plant Research International, Wageningen, the Netherlands.
The researchers noted that freezing and storing of the raspberries did not significantly affect the antioxidant activity of the berries, although the concentration of vitamin C was halved by the freezing process.
"Raspberry represents a diverse source of potentially healthy antioxidants and as such can provide a useful component to our daily diet," concluded the scientists.
Only last year, sales of blueberries in the UK rocketed on the back of positive newspaper and magazine articles that heralded the humble blueberry as a SuperFood on the basis of compounds that could lower cholesterol levels.
Blueberry sales grew by £14.7m in the last year to reach £26.2m, according to information from retail analysts Taylor Nelson Sofres.