Phenolic composition and antioxidant capacity of newly developed strawberry lines from British Columbia and Quebec

The total phenolic composition (TPC) and the total antioxidant capacity (TAC) of eleven strawberry genotypes selected from the AAFC breeding program (BC2-72-17, BC2-90-43, BC96-33-4 and BC98-49-34 from British Columbia; and APF937-1, APF939-71, LL981-24, LL9819-14, LL982-14, LL0220-10 and SJ9332-7 from Quebec) were evaluated using high-performance liquid chromatography (HPLC) and ferric reducing/antioxidant power (FRAP) assays. TPC and TAC values of these genotypes were compared to those of four commercially grown cultivars ('Chambly,' 'Kent,' 'Veestar' and 'Yamaska') and the effects on fruit quality and shelf life were studied. Several groups of phenolic compounds, including anthocyanins, flavonols, hydroxycinnamic, ellagic and benzoic acids, were identified and quantified by HPLC. Significant variation of TPC was observed between genotypes, and anthocyanins were found to be the predominant phenolic group, contributing to 79.2% of the TPC. A significant correlation (r = 0.96) was observed between TPC and anthocyanin content. BC2-72-17 had the highest anthocyanin content and differed significantly from the other genotypes. Although the highest TPC (2123.8 μg g-1) was found in BC2-72-17, this genotype did not have the highest antioxidant capacity. The highest TAC (2259.0 μg g-1) was found in BC2-90-43, indicating that other phenolics may have made a greater contribution than anthocyanins to the high TAC. At room temperature, LL0220-10, SJ9332-7 and 'Yamaska' had a three-day shelf life, while it was only two days for all other genotypes. There was a negative correlation between shelf life and ellagic acids, flavonol and anthocyanin levels but this relationship was not significant (p > 0.0.). The fruit soluble solids content (SSC) and titratable acidity (TA) varied between genotypes. 'Veestar' and LL981-24 had the highest SSC (7.5). These results point to the importance of identifying genotypes with high phenolic monomer activities in screening for lines with high TAC, to ensure their use in breeding programs aimed at improving the nutritional value of strawberry. Copyright © Taylor & Francis Group, LLC.