| Abstract | Antioksidansi koji se nalaze u voću i povrću imaju izuzetnu vrijednost u prevenciji kroničnih
bolesti, poput kardiovaskularnih bolesti, različitih vrsta karcinoma, dijabetesa i nekih neuroloških
bolesti. Jabuka je jedna od najpoznatijih i najviše korištenih sirovina danas, bilo da se radi o preradi u
određene proizvode ili o potrošnji u svježem stanju. Kožica jabuka je izuzetno bogata bioaktivnim
spojevima (npr. polifenolima) i predstavlja visokovrijedni otpadni produkt prerade jabuka koji se može
koristiti u obogaćivanju različitih proizvoda u pogledu nutritivne vrijednosti, odnosno u kreiranju
funkcionalne hrane. Cilj ovog rada bio je istražiti antioksidativnu aktivnost i udio polifenolnih tvari u
kožici jabuka. U radu su korištene četiri vrlo cijenjene sorte jabuka: Top red delicious, Jonagold, Fuji i
Gala. Vrijednosti ovih parametara dobivenih u kožici uspoređeni su sa vrijednostima dobivenim u pulpi
sa/bez kožice. Unutar svake ispitivane sorte, antioksidativna aktivnost i ukupni fenoli bili su najviši u
kožici, zatim u pulpi s kožicom i na kraju, pulpi bez kožice. Najviše vrijednosti polifenolnih tvari u kožici
imala je sorta Fuji (6,42 gL-1), a najniže sorta Jonagold (4,61 gL-1). Najveću antioksidativnu aktivnost
imala je sorta Top red delicious (7,54 mmoltrolox100mL-1), dok su sorte Jonagold i Gala imale najniže
vrijednosti (3,56 i 3,53 mmoltrolox100mL-1). U radu je ispitana i topljiva suha tvar, pH, udio ukupnih
kiselina, udio antocijana u svim sortama, kao i čvrstoća plodova. Najviše vrijednosti topljive suhe tvari i
ukupnih kiselina zabilježene su u sorti Fuji a najniže u sorti Gala. Udio antocijana bio je najniži u sorti
Jonagold, što je i razumljivo zbog manje obojenosti plodova u odnosu na ostale sorte. Sorta Fuji imala
je najviše vrijednosti čvrstoće plodova a sorta Jonagold najniže izmjerene vrijednosti čvrstoće. |
| Abstract (english) | Antioxidants found in fruits and vegetables are extremely valuable in the prevention of chronic diseases such as cardiovascular disease, different types of cancer, diabetes and certain neurological diseases. Apple is one of the best known and most widely used raw materials today whether the processing of certain products or consumption of fresh state. Apple foreskin is extremely rich in bioactive compounds (eg, polyphenols), and a high-quality waste product processing apples that can be used in the enrichment of different products in terms of nutritional value, or the creation of
functional foods. The aim of this study was to investigate the antioxidant activity and the proportion of polyphenolic substances in the skins of apples. In this work used four highly prized varieties of apples: Top Red Delicious, Jonagold, Fuji and Gala. The values of these parameters obtained in the foreskin were compared with values obtained in the pulp with / without a foreskin. Within the all examined varieties, antioxidant activity and total phenols were the highest in the skin, then the pulp with the skin and in the end, the pulp without foreskin. The highest values of polyphenolic substances in the skins had a variety Fuji (6.42 gL-1), and lowest cultivar Jonagold (4.61 gL-1). The greatest antioxidant activity
had a variety Top Red Delicious (7.54 mmoltrolox100mL-1), while the varieties Jonagold and Gala had the lowest values (3.56 and 3.53 mmoltrolox100mL-1). Furthermore, in this work has been tested
soluble solid content, pH, total acid, the proportion of anthocyanins in all varieties and firmness of the fruit. Soluble solid and total acid had the highest values of the varieties Fuji and Gala varieties in the lowest. Amount of anthocyanin was the lowest in cultivars Jonagold, which is understandable because less coloring than other varieties. Fuji variety had the highest values of fruit firmness and variety Jonagold the lowest measured values. |
