Flowers, leaves and fruits of hawthorn plant are traditionally used for treating diseases like hypertension and atherosclerosis. The medicinal effects of the plant are generally attributed to its phenolic compounds. However, the fruits are perishable materials because of their high content of water, and generally dried and stored to be used outside its season. The main aim of this research was to investigate the effect of different drying methods on phenolic compounds of the hawthorn fruit. Fruits were collected from the wild growing trees in Turkey. De-seeded fruits were dried in freeze-, oven- (60 oC) and microwave pretreated oven drying (microwave application for 5 min at 360 W before drying at 60 oC) methods and analyzed for antioxidant activity, phenolic compounds, total phenolic content and color parameters. Total phenolic content of fresh hawthorn fruits was found as 13.36 mg g-1 DW. Oven- and microwave pretreated oven drying methods had a reductive effect on total phenolic content and antioxidant activity of fruits when compared to freeze drying method. (-)-Epicatechin (994.10 mg kg-1 DW), rutin (765.30 mg kg-1 DW), and procyanidin B2 (553.80 mg kg-1 DW) were the main phenolics of the fruit. Lowest values of these three compounds were observed in oven-dried fruits. Microwave pretreatment oven drying method resulted in browner product. Although the highest phenolic concentration and antioxidant activity were occurred in freeze-dried sample, microwave pretreatment before oven drying could be applied to reduce the time and cost of drying in terms of phenolic compounds and antioxidant activity.

Ekşikara (Vitis vinifera L.) is a poorly known native Turkish grape cultivar, which is being cultivated for thousands of years for table consumption, raisin, and grape molasses production. The aim of this study was to investigate the phenolic profile of whole berry, skin, and seeds of the cultivar and to determine the effect of harvesting year and altitude of the vineyard location. The grape samples were collected from two vineyards, located at 1000 and 1500 m of altitude in year 2014 while it was collected from 1500 m of altitude in year 2015. In addition to phenolic profile, antioxidant activity, total phenolic, anthocyanin, and tannin contents, and fatty acid profile of seed oil were also analyzed. In this study, anthocyanins, resveratrol, rutin, and isorhamnetin-3-glucoside were mainly found in skin while monomers and dimers of flavan-3-ols were present mainly in the seed. Altitude had a drastic effect on phenolic compounds as well as on the antioxidant activity of whole berry, skin, and seeds.

The aims of this research were to investigate the usability of black grape pomace in the production of shalgam juice, which is a traditional fermented Turkish beverage, to transform the pomace into the high value‐added product and to enrich the shalgam juice with phenolic compounds. Black grape pomace and black carrot were used as the sources of polyphenols and five different formulations were obtained according to the amounts of black carrot and black grape pomace. During the fermentation, the samples were taken at different periods and analyzed for anthocyanins, phenolic compounds, antioxidant activity, and tannin content. Gentisic, caffeic, ferulic, coumaric, and chlorogenic acids, catechin, glucosides of kaemferol and isorhamnetin, resveratrol, rutin, cyanidin‐3‐xylosylglucosylgalactoside, cyanidin‐3‐xylosylgalactoside, cyanidin‐3‐xylosylglucosylgalactoside acylated with sinapic acid, ferulic acid, or coumaric acid, and glucosides of cyanidin, petunidin, and malvidin were identified in the shalgam juices that contained both black grape pomace and black carrot in their formulation. Some of these polyphenols were not detected detect in the shalgam juices that were produced from only the black carrot or black grape pomace. During the fermentation, a decrease in the amount of anthocyanins originated from black carrots and an increase in the amount of anthocyanins orginated from black grape pomace were determined. Black grape pomace addition to the formulation before the fermentation caused an increase in the amount of tannin in the shalgam juice samples. Consequently, it is thought that black grape pomace can be fruitfully evaluated in shalgam juice production and can be enhanced by polyphenolic profile of shalgam juice.