Therefore, the TAC measurements of crude berry extracts
do not reflect the entire picture, and the contribution of
individual compounds must be examined. Individual
compounds can be identified using mass spectrometry,
while their antioxidant capacity can be assessed using the
recently developed on-line high-performance liquid
chromatography (HPLC) antioxidant analysis, which
measures the antioxidant capacity of each individual
compound eluted from an HPLC separation. The results
obtained provide an overview of the phytochemical composition
and the contribution of each compound to the
antioxidant activity of the berry. For example, applying
the method to raspberries revealed that about half of
their antioxidant activity was due to the presence of
ellagitannins, a class of phenolic compounds predominantly
found in fruit from the Roseaceae family, while
more generally occurring antioxidants like vitamin C
(20%) and anthocyanins (25%) had lower contributions.2
In most other fruits, the contribution of vitamin C to TAC
is much higher, e.g. 30–35% in some strawberry varieties3
where other specific compounds like pelargonidin-3-
glucoside may also account for up to 25% of TAC.3 Consequently,
different berries may have a unique impact on
consumer health due to the different contributions of
specific compounds to their TAC. Understanding the link
between the antioxidant capacity of individual components
and the bioactivities of different berries may direct
the biotechnological improvement of new berry varieties.