Now showing 1 - 7 of 7
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Influence of seeds’ age and clarification of cold-pressed raspberry (Rubus idaeus L.) oil on the DSC oxidative stability and phase transition profiles

2023, Rajagukguk, Yolanda Victoria, Islam, Mahbuba, Tomaszewska-Gras, Jolanta

After cold-pressing, small particles of seed residue remain in raspberry seed oil (RSO), even after passing it through cold filtration. The removal of the remaining seed residue is rather an alternative option to improve the visual properties of RSO. This study investigated the influence that the seeds’ age (0, 10, 20 months) and clarification process after pressing has on the oxidative stability and phase transition of RSO by means of differential scanning calorimetry (DSC). The results proved that the oil centrifugation process reduces the DPPH radical scavenging activity and oxidative stability measured by p-anisidine value (p-AnV) and DSC oxidation induction time (OIT) at 120 °C of all RSO samples, regardless of the age of the seeds (p ≤ 0.05). No significant differences were observed on the DSC melting and crystallization properties at 1 °C/min after the oil clarification by centrifugation (p > 0.05). The storage time of raspberry seeds, i.e., 10 and 20 months after expiry date, influenced the quality deterioration of RSO, as measured by higher p-AnV, lower DPPH, and OIT values (p ≤ 0.05). The results presented provide new information about oil production processing, suggesting that producers should reconsider giving up the clarification process of oil, since it lowers all quality parameters.

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Oxidative stability assessment of industrial and laboratory-pressed fresh raspberry seed oil (Rubus idaeus L.) by differential scanning calorimetry

2023, Rajagukguk, Yolanda Victoria, Islam, Mahbuba, Siger, Aleksander, Fornal, Emilia, Tomaszewska-Gras, Jolanta

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Advanced authenticity screening of commercial berry seed oils using full FTIR spectra and DSC curves coupled with chemometrics

2025, Rajagukguk, Yolanda Victoria, Tomaszewska-Gras, Jolanta

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Fusion of DSC and FTIR data with physicochemical profiling to distinguish berry seed oils by extraction methods

2025, Rajagukguk, Yolanda Victoria, Grygier, Anna, Siger, Aleksander, Waśkiewicz, Agnieszka, Ryszczyńska, Sylwia, Tomaszewska-Gras, Jolanta

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Physicochemical characteristics of cold-pressed blackcurrant-, strawberry-, and raspberry seed oils during storage and its influence on thermo-oxidative stability

2024, Rajagukguk, Yolanda Victoria, Islam, Mahbuba, Grygier, Anna, Siger, Aleksander, Rudzińska, Magdalena, Tomaszewska-Gras, Jolanta

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Thermal and spectroscopic profiles variation of cold-pressed raspberry seed oil studied by DSC, UV/VIS, and FTIR techniques

2023, Rajagukguk, Yolanda Victoria, Islam, Mahbuba, Grygier, Anna, Tomaszewska-Gras, Jolanta

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Assessment of Hemp Seed Oil Quality Pressed from Fresh and Stored Seeds of Henola Cultivar Using Differential Scanning Calorimetry

2023, Islam, Mahbuba, Rajagukguk, Yolanda Victoria, Siger, Aleksander, Tomaszewska-Gras, Jolanta

Cold-pressed hemp (Cannabis Sativa L.) seed oil has become very popular amongst consumers and researchers, due to its manifold application in food and medicine industry. In this study, oils pressed from stored and fresh hemp seeds of the Henola cultivar were analyzed. Determination of the acid value (AV) and color of oil (a* parameter) revealed significant differences between the two groups of oils (fresh and stored seeds) in contrast to the peroxide value (PV), p-anisidine value (p-AV), and fatty acid composition. On the other hand, isothermal and non-isothermal assessments of the thermo-oxidative stability by differential scanning calorimetry (DSC) showed no significant differences in oxidation induction time (OIT) as well as in onset temperature (Ton) between two groups of oils (p > 0.05). The DSC isothermal test (OIT 160) showed significant correlations with mono- and polyunsaturated fatty acids as well as with values of AV and a* (p ≤ 0.05), in contrast to the non-isothermal test, for which correlations were not significant (p > 0.05). However, the best distinction of both groups of oils was obtained analyzing all results together (DSC, fatty acid and tocochromanols composition, color, and oxidative stability results) by principal component analysis (PCA).