Juices Enriched with Phenolic Extracts from Grapes

0491278 - ÚVGZ 2019 RIV CZ eng J - Journal Article
Kulichová, J. - Buaong, M. - Balík, J. - Híc, P. - Tříska, Jan - Vrchotová, Naděžda
Juices Enriched with Phenolic Extracts from Grapes.
Czech Journal of Food Sciences. Roč. 36, č. 3 (2018), s. 261-267. ISSN 1212-1800. E-ISSN 1805-9317
R&D Projects: GA MŠMT(CZ) LO1415
Institutional support: RVO:86652079
Keywords : antioxidant capacity * catechin * epicatechin * grape pomace * grape seeds * press oil cak
OECD category: Food and beverages
Impact factor: 0.846, year: 2018

The paper describes the preparation and evaluation of phenolic extracts from waste materials - pomace (grape marc), seeds and press oil cake of the white grape variety Irsai Oliver (Vitis vinifera L.) and their addition to apple and grape juices to increase the nutritional properties. The waste samples were extracted using 50 or 80% ethanol (v/v). Some of the samples were extracted for 60 min at boiling temperature under reflux, the remainder were processed for 24 h on a shaker at room temperature. The highest antioxidant capacity (as measured using DPPH (758 ± 28 mM Trolox/kg of extracted matter)) and content of total polyphenols (74 ± 0.7 g gallic acid/kg of extracted matter) were found in the extract of the seeds obtained through extraction using 50% ethanol (v/v) at boiling temperature for 60 minutes. The press oil cake extract obtained by means of 80% ethanol (v/v) at boiling temperature for 60 min was evaluated as the best for enriching the sensory quality of apple and grape juices. The addition of 1 g of freeze-dried press oil cake extract to 1 l of juice increased the antioxidant capacity and total polyphenol content two-fold. © 2018 Czech Academy of Agricultural Sciences. All Rights Reserved
Permanent Link: http://hdl.handle.net/11104/0285288