Effect of growing location on anthocyanin content and total antioxidant capacity of haskap (Lonicera caerulea L.) berry: A preliminary investigation

The haskap has been successfully cultivated in many geographical zones in Canada. We investigated whether the latitude has any impact on the anthocyanin accumulation and total antioxidant capacity in the haskap berry. The measured quality attributes were compared with that of the blueberry. Haskap ‘Aurora’ berries were collected from Yukon, British Columbia, Saskatchewan, and Nova Scotia in Canada, and blueberries were collected from Nova Scotia. Cyanidin-3-O-glucoside (C3G), the most abundant anthocyanin of haskap berry, the total anthocyanins, the total polyphenols, the soluble solids (°Brix), the pH value, the total antioxidant capacity, and the moisture content were determined. The results revealed that the total anthocyanin, total phenolic content, and antioxidant capacity of the haskap range between 88 to 273 mg C3GE/100 g fresh weight (FW), 256 to 442 mg GAE/100 g of FW, and 27 to 52 µmol TE/g FW, respectively. The liquid chromatography-mass spectrometry (UPLC/MS) analysis revealed that the C3G contained in the haskap berry is highly dependent on the harvest stage. Among the samples, the haskap berry harvested on July 19, 2019, from the Yukon had the highest C3G content. Interestingly, the total anthocyanin content of the haskap berry is comparable to that of the lowbush blueberry, but higher than the highbush blueberry. A systematic multi-year experiment employing many cultivars and growing locations is recommended to better understand the latitude effect.