## 2 Results and Discussion  
In this study, the peroxide number, which determines the amount of primary oxidation products, of the analyzed oils ranged from 7.39 to 8.78 med O\({}_{2}\)/kg. The permissible amount of peroxides in cold-pressed oils is much higher than that in refined oils (<5 meq O\({}_{2}\)/kg) [10]. The peroxide value of the cold-pressed oils analyzed in the study did not exceed 10 meq O\({}_{2}\)/kg, which is the value specified in the standards [10]. This suggests that the chemical composition of lipids (fatty acid composition, content of natural antioxidants and pro-oxidants) and therefore the susceptibility to environmental factors determine the oxidative changes occurring in natural, unrefined oils [11]. All the tested oils were characterized by low acid values (Table 1), which proves the low degree of hydrolysis and the small amount of free fatty acids. The acid values of oils reported in other studies were significantly higher. For instance, a study by [PERSON] et al. [11] showed that blackberry and raspberry oils had an acid value of 6.85-7.05 and 17.18-17.86 mg KOH/g, respectively. Another study [12] presented acid values of 2.71-3.02, 2.60-3.45, and 2.72-3.73 mg KOH/g for cold-pressed strawberry seed oil, raspberry oil, and blackberry oil, which are similar to the values obtained in this study. The tested oils were products of good quality, not exceeding the prescribed norms, with the exception of acid value of raspberry oil, where the values were slightly above normal. The chemical characteristics of cold-extracted blueberry, cranberry, raspberry, and cuckooflower native seed oils were evaluated to determine their fatty acid composition, positional distribution of fatty acids, and TAG profile. In addition, the effect of minor components, including tocopherols and pigments, on the oxidative stability of the studied oils was investigated. The results of a previous study by [PERSON] et al. [9] indicated that all the tested berry seed oils contained significant levels of palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1), LA (C18:2u-6), and ALA (C18:3u-3), along with a favorable ratio of \(\omega\)-6/\(\omega\)-3 fatty acids (0.2-1.69). Moreover, palmitic acid, stearic acid, oleic acid, and ALA were predominantly distributed on the terminal positions [9]. In the present study, fatty acid analysis (Table 2) revealed a high content of 18:3 \(n\)-3 acid in the analyzed oils as follows: cress--35.03%, raspberry--31.1%, blueberry--28.99%, and cranberry--34.91%. C 18:1 was detected as the predominant species in the tested berry seed oils: cress--28.24%, raspberry--10.99%, blueberry--21.02%, and cranberry--20.23%. Vegetable oils with a low n--6/n--3 acid ratio are especially beneficial to human nutrition. Blueberry, cranberry, raspberry, and cuckooflower oils have an n-3/n-6 ratio of 1-2. These oils can be included in the diets of people who are recalcitrant following heart attacks or cardiac surgeries. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Characteristics**} & **Blueberry** & **Cranberry** & **Raspberry** & **Cuckooflower** \\  & **Seed Oil** & **Seed Oil** & **Seed Oil** & **Seed Oil** \\ \hline Content of oil (\% dry matter) & 18.06 \(\pm\) 0.32 & 14.52 \(\pm\) 0.31 & 16.20 \(\pm\) 0.29 & 20.32 \(\pm\) 0.28 \\ Moisture content of seeds (\%) & 8.46 \(\pm\) 0.11 & 7.76 \(\pm\) 0.10 & 7.82 \(\pm\) 0.11 & 9.04 \(\pm\) 0.13 \\ Acid value (mg KOH/g) & 2.14 \(\pm\) 0.00 & 1.78 \(\pm\) 0.00 & 4.14 \(\pm\) 0.01 & 1.38 \(\pm\) 0.00 \\ Peroxide value (meq O\({}_{2}\)/kg) & 8.78 \(\pm\) 0.02 & 7.39 \(\pm\) 0.01 & 8.45 \(\pm\) 0.03 & 8.59 \(\pm\) 0.04 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Physicochemical properties of blueberry, cranberry, raspberry, cuckooflower seed oils obtained by sonification. Seed oils from berries such as blueberries, raspberries, and cranberries are a rich source of PUFA.