Characteristics of Oil from Domestic Pumpkin

Abstract

Ulje semena tikve karakteriše se visokim udelom nezasićenih masnih kiselina, tokoferola, karotenoida (posebno β-karotena) i fitosterola. Dodatnu vrednost ulju daje proizvodnja tikve bez upotrebe agrohemikalija, što je slučaj sa domaćom tikvom uzgajanom kao sporedna biljna kultura u gazdinstvima pojedinih sela Zapadne i Centralne Srbije. Cilj rada bio je ispitati osnovne karakteristike ulja semena domaće tikve. Ispitana su ulja semena 19 različitih genotipova domaće tikve prikupljenih na širem području Centralne i Zapadne Srbije. Pre analize, seme je osušeno na sobnoj temperaturi. Ulje je izolovano na dva načina: hladnim presovanjem (pužna presa, OPW 650, Gorenje, Slovenija) i ekstrakcijom (Solvent extractor, Velp Scientifica 148, Italija). Nakon presovanja, ulje je ostavljeno da se istalože balastne materije na 4 °C. U bistrim uljima meren je sadržaj vlage i isparljivih materija gravimetrijskim sušenjem na 105 °C do konstantne mase, a zatim je izmeren indeks refrakcije na 23 °C pomoću Abbe-ovog refraktometra. Sadržaj sirovog ulja određen je pomoću petroletra. Rezultati su pokazali da se sadržaj ulja u semenu kretao od 2,68% do 42%, sa srednjom vrednošću od 25,73%. Boja hladno presovanih ulja značajno je varirala od žutozelene do tamnosmeđe, što ukazuje na razlike u sadržaju pigmenata. Sadržaj vlage i isparljivih materija varirao je od 0,08% do 0,2%, sa prosekom od 0,14%. Indeks refrakcije varirao je od 1,4700 do 1,4730, sa prosečnom vrednošću od 1,4712. Minimalne razlike mogu ukazati na neznatne varijacije u masnokiselinskom sastavu. Na osnovu rezultata može se zaključiti da postoje značajne razlike u sadržaju ulja semena 19 genotipova domaće tikve, dok su boja, vlaga i indeks refrakcije pokazali homogeni kvalitet svih uzoraka.Pumpkin seed oil contains a high level of unsaturated fatty acids, tocopherols, carotenoids (particularly β-carotene), and phytosterols. Cultivation of pumpkins without agrochemical use enhances the oil’s value, as exemplified by domestic pumpkins grown as secondary crops on small farms in Western and Central Serbia. The objective of this study was to investigate the characteristics of domestic pumpkin seed oil. Seed oils from 19 genotypes collected from Central and Western Serbia were analyzed. The seeds were air-dried at room temperature, and oil was extracted using two methods: cold pressing (screw press, OPW 650, Gorenje, Slovenia) and solvent extraction (Velp Scientifica 148, Italy). Moisture and volatile matter were determined by gravimetric drying at 105 °C, and the refractive index was measured at 23 °C using an Abbe refractometer. The oil content ranged from 2.68% to 42.00%, with an average of 25.73%. The color of cold-pressed oils varied from yellow-green to dark brown, reflecting differences in pigment composition. Moisture and volatile matter content ranged between 0.08% and 0.20% (average 0.14%), while the refractive index ranged from 1.4700 to 1.4730, with an average of 1.4712. The narrow range of refractive index values indicates a high degree of homogeneity among genotypes. The results indicate significant variability in oil content among genotypes, while oil color, moisture, and refractive index remained within quality standards, confirming good quality of all analyzed samples