Naslov
Effect of conditioning temperature on nutritional properties and quality of nonrefined rapeseed oil

Autori
Kraljić, Klara ; Škevin, Dubravka ; Pospišil, Milan ; Obranović, Marko ; Neđeral, Sandra ; Balać, Tanja, Stjepanović, Tatjana

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

Skup
8th International Congress of Food Technologists, Biotechnologists and Nutritionists

Mjesto i datum
Opatija, Hrvatska, 21.10.2014. - 24.10.2014

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
conditioning; nutritional value; rapeseed oil; sensory quality; volatile components

Sažetak
Conditioning of the seed prior the oil extraction is conducted to improve oil yield but it can also significantly increase amount of bioactive compounds. Despite these findings, consumers still prefer cold pressed oils over nonrefined ones. The aim of this study was to determine how different temperatures of conditioning influence nutritional properties and quality of rapeseed oil. Oil was produced from rapeseed cultivar PR 46 W20 (Pioneer) by cold pressing (CP) and by pressing seeds conditioned at 60, 80 and 100ºC for 30 min (HP60, HP80, HP100). The quality parameters of all produced oils were within limits of national regulations. Production process significantly affected unsaturated fatty acids of nonrefined oils but changes did not correlate with temperature increase. Conditioning of the rapeseed increased nutritional value of the oils because it did not change composition and content of tocopherols and at the same time it increased levels of plastochromanol-8 and polyphenols. Amount of canolol, polyphenol that was in cold pressed oils detected only in traces, linearly increased with temperature used. Conditioning also significantly affected profile of volatile components. The dominant volatile components of cold pressed rapeseed oil were isothiocyanates and sulfur components, together making 70% of total volatile components. Conditioning at 60°C furthermore increased their content (80% of total) probably because of higher myrosinase activity. Conditioning at 80 and 100°C significantly decreased levels of isothiocyanates and sulfur components at the same time increasing amount of nitrile components that are formed during the heating process. In addition, conditioning at 100 °C caused the formation of pyrazines, components responsible for nutty and roasted flavor of the oil. Despite significant difference in volatile components profile, all produced oils were given high scores on sensory evaluation by panel, and no significant difference between the sensory scores was found.

Izvorni jezik
Engleski

Znanstvena područja
Prehrambena tehnologija

POVEZANOST RADA