Naslov
Changes in oxidation stability of fish oil during thermic treatment and storage under poor conditions

Autori
Šimat, Vida ; Čagalj, Martina ; Vlahović, Jelena ; Skroza, Danijela ; Ljubenkov, Ivica ; Generalić Mekinić, Ivana

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

Izvornik
Proceedings of the 46th WEFTA CONFERENCE "From Local Fish to Global DISH“ / Vidaček, Sanja - Zagreb : Prehrambeno-biotehnološki fakultet Sveučilišta u Zagrebu, 2016, 28-32

ISBN
978-953-6893-10-2

Skup
46th WEFTA CONFERENCE "From Local Fish to Global DISH“

Mjesto i datum
Split, Hrvatska, 12.10.2016. - 14.10.2016

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Cod liver oil, Oxidation stability, Peroxide value, p-anisidine value, TBARS

Sažetak
Fish oil is highly susceptible to oxidation and spoilage, which makes its application in different foods or thermal processing quite limited. To investigate this, oxidation stability of cod liver oil was determined during five hours of cooking at 95 °C and in poor storage conditions (direct sunlight exposure and high summer room temperatures over three months). Deterioration of the oil and its oxidation stage were determined through analyses of peroxide value, p-anisidine value, thiobarbituric acid reactive substances (TBARS), free fatty acids (FFA) and composition of fatty acids. Additionally, precision of listed analytical methods was determined. The results showed increasing oxidation with cooking time resulting in high peroxide values (> 40 mmol O2/kg). In oil samples stored in poor conditions, an increase of p-anisidine value was observed. TBARS increased after 5 hours of cooking, while FFA and fatty acid composition did not vary much between the samples. The percentage of the most important n-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) was not significantly changed during thermic treatment nor poor storage conditions. The share of the total monounsaturated fatty acids in cooked oil samples decreased from the average 46% to 31% after 5 hours at 95 °C. Opposite to that, the total polyunsaturated fatty acid increased after 5 hours of cooking from an average of 32% to 46%. Relative standard deviation (RSD) of ten parallel analyses of oil samples was used to determine the uncertainty of methods. Analytical methods for peroxide value, p-anisidine value and thiobarbituric test showed more certainty at higher concentrations of analyte, while average RSD for FFA was 18.89%, indicating that >4 repetitions are needed to get accurate results.

Izvorni jezik
Engleski

Znanstvena područja
Prehrambena tehnologija

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