Naslov
Stabilnost polifenola, inaktivacija enzima i fizikalno-kemijski parametri tijekom proizvodnje koncentriranog soka od bobica bazge
(The Polyphenols Stability, Enzyme Activity and Physico-Chemical Parameters during Producing Wild Elderberry Concentrated Juice)

Autori
Galić, Ante ; Dragović-Uzelac, Verica ; Levaj, Branka ; Bursać Kovačević, Danijela ; Pliestić, Stjepan ; Arnautović, Sabina

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
20. Hrvatski i 3. Međunarodni kongres tehnologa za posliježetvenu tehnologiju, ZRNKO 08 / Pliestic S. - Zagreb : Agronomski fakultet Sveučilišta u Zagrebu, 2008, 116-117

ISBN
978-953-6135-76-9

Skup
20. Hrvatski i 3. Međunarodni kongres tehnologa za posliježetvenu tehnologiju, ZRNKO 08

Mjesto i datum
Stubičke Toplice, Hrvatska, 18.11.2008. - 20.11.2008

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
bazga; polifenoli; antocijani; enzimi; fizikalno-kemijski parametri
(elderberry; polyphenols; anthocyanins; enzymes; physico-chemical parameters)

Sažetak
The influence of processing wild elderberry into concentrated juice on polyphenols (total phenols, flavonoids, non-flavonoids, anthocyanins, flavan-3-ols, hydrolysed tannins) stability, activity of polyphenol oxidase (PPO) and peroxidase (POD), and changes of physico-chemical parameters (total and soluble dry matter, total acidity, pH, sugars) were investigated. The amounts of total phenols, flavonoids, non-flavonoids, falvan-3-ols and hydrolysed tannins were analyzed using Folin-Ciocalteu colorimetric method, while the total anthocyanins were determined by bisulphite bleaching method. Total phenols ranged from 25.87 mg/g DM to 38.87 mg/g DM. Total anthocyanins were the most abundant polyphenols in all investigated samples (raw elderberries, elderberries after blanching, elderberry juice after disintegration and pressing, concentrated elderberry juice) and their concentration ranged from 13.12 mg/g DM to 25.67 mg/g DM. Other polyphenols determined in high concentration were hydrolysed tannins, followed flavan-3-ols, flavonoids and nonfavonoids. After blanching, the concentration of all polyphenols did not decreased significantly. After disintegration of elderberries the concentration of all polyphenols increased, probably due to inactivation of PPO and POD, and better isolation of polyphenols from homogenized purée. During processing of elderberry juice into concentrated juice most polyphenols were stable. Total acidity and pH value were not changed during processing, whereas the amounts of total and reducing sugar increased after pressing and additionally after concentration. The obtained results suggest that raw elderberries as well as elderberry concentrated juice are high potential source of polyphenols especially anthocyanins.

Izvorni jezik
Hrvatski

Znanstvena područja
Kemija, Biologija, Poljoprivreda (agronomija)

POVEZANOST RADA