Drying of blueberry (Vaccinium spp.) and cornelian cherry (Cornus mas L.) using different methods and determination of bactericidal effect of the dried product on e.coli (Escherichia coli) under in vitro conditions

In this study, different drying methods were applied to two types of fruit, that is, cornelian cherry CC (Cornus mas L.) and blueberry BB (Vaccinium spp.). During the research work, both CC and BB were exposed to natural drying, convective drying, microwave drying, and the combined microwave-convective drying. The initial moisture content of cornelian cherry (CC) at 72.56 ±0.18% was reduced down to 10.27 ± 0.13%; whereas the moisture content of blueberries (BB) initially at 84.76 ± 0.20% was reduced to 10.03 ± 0.09%. During the study, it has been found that apart from natural drying, convective drying has the longest drying time and the highest values for the specific energy consumption. The study concludes that both CC and BB show high antioxidant capacity and comprises of various amounts of polyphenolic compounds. Moreover, as per the total antioxidant capacity, CUPRAC is the most suitable method. The anthocyanin and vitamin C content for both the fruits showed high values, which concludes that CC and BB can be an essential source of daily vitamin C consumption. Even though both CC and BB contains high values of anthocyanin, no antimicrobial activity was found for both the fruit samples. Keywords: Blueberry, cornelian cherry, drying, antioxidant capacity, anthocyanin content, antimicrobial activity