Naslov
Microwave-assisted extraction of tannins from grape skin pomaces

Autori
Ćurko, Natka ; Kelšin, Karla ; Dragović-Uzelac, Verica ; Tomašević, Marina ; Kovačević Ganić, Karin

Vrsta, podvrsta i kategorija rada
Radovi u zbornicima skupova, cjeloviti rad (in extenso), znanstveni

Izvornik
Proceedings of 9th International Congress of Food Technologists, Biotechnologists and Nutritionists / - , 2018, 27-31

Skup
9th International Congress of Food Technologists, Biotechnologists and Nutritionist

Mjesto i datum
Zagreb, Hrvatska, 03.10.2018. - 06.10.2018

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
grape by-products ; grape skin pomaces ; microwave-assisted extraction (MAE) ; tannins

Sažetak
Microwave-assisted extraction (MAE) is valuable alternative to conventional extraction due to the possibility to reach comparable extraction yield with shorter extraction time. The wine by-products (grape skin and seed pomaces) are rich source of phenolic compounds, among others tannins, with diverse bioactive properties. The aim of this study was to evaluate a single and joint effects of different variables under microwave irradiation i.e. solvent concentration, time and temperature on the extraction of tannins from grape skin pomaces. Concentrations of tannins were determined by spectrophotometry using acid hydrolysis method. All tested variables showed significant impact on the extraction yields of total tannins from grape skin pomaces, but solvent concentration and temperature showed to be the most responsive ones. Highest concentrations were extracted with 60% (v/v) of methanol at 60 °C during 9 min. Application of consecutive MAE cycles on three cultivars (Cabernet Sauvignon, Merlot and Teran) revealed that 98.8-99.7% of total tannins were extracted within six cycles. Grape skin pomaces of Teran, compared to Cabernet Sauvignon and Merlot, showed significantly higher concentrations of total tannins.

Izvorni jezik
Engleski

Znanstvena područja
Prehrambena tehnologija

POVEZANOST RADA