Evaluation of black grape pomace, a fruit juice by‐product, in shalgam juice production: Effect on phenolic compounds, anthocyanins, resveratrol, tannin, and in vitro antioxidant activity

Abstract

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.

Comparison of Aroma and Taste Profiles of Kiwi Wine Fermented with/without Peel by Combining Intelligent Sensory, Gas Chromatography-Mass Spectrometry, and Proton Nuclear Magnetic Resonance

“…KW was produced by adapting the method described by Zhang et al to the present experimental plan [ 7 ]. Uniformly sized and intact Pujiang (Chengdu, China) kiwifruits were selected and cleaned.…”

“…To optimize resource usage, researchers are increasingly experimenting the production of fruit wines by fermenting pomace from a variety of fruits. For instance, the substitution of 75% grape pomace with black carrots during the fermentation of shalgam juices enhances the final product’s concentrations of resveratrol, catechin, rutin, kaempferol-3-O-glucoside, isorhamnetin-3-O-glucoside, cyanidin-3-O-glucoside, petunidin-3-O-glucoside, and malvidin-3-O-glucoside [ 7 ]. Lindsay et al investigated the fermentation of the pomace of apple, orange, and carrot using Brettanomyces bruxellensis .…”

“…The pomace of kiwifruit contains phenols, organic acids such as quinine and caffeic acid and their derivatives, antioxidant components, and various aroma precursors [ 9 , 10 ]. The kiwifruit peel contains beneficial components, including chlorophyll, polyphenols, and flavonoids, which contribute to its antioxidant activity [ 7 ]. Furthermore, it is worth highlighting that the peel of the kiwifruit contains a higher concentration of phenols, flavonoids, and ascorbic acid compared to the pulp [ 8 ].…”