# Enhancing Brioche Bread with Emulsified Seed and Nut Oils: Nutritional and Sustainable Benefits
## 3 Results and Discussion  
### Oil Quality  
Table 1 shows the results obtained for the oil parameters analyzed. Chia seeds, well known for their fiber content, also have a significant oil percentage (25-38%) [30]. In this study, the oil yield from chia seeds was 20.07 \(\pm\) 0.81%, slightly lower than previously reported yields of 28% using a screw press [30] and 23.86% using other methods [31]. These differences can be attributed to the type of press used, since crew presses generate heat that increases yield but can compromise oil quality. For pumpkin seeds, oil yield depends heavily on the variety, typically ranging from 28 to 50%. In this study, the yield was significantly lower than those previously reported in the literature, where yields around 30.7% (screw press) and up to 42% (solvent extraction) [31; 32] can be found. Melon seeds are another oil source, with lipid levels between 25% and 30.5% [33]. The oil yield obtained in this study was 16.07 \(\pm\) 0.92%, which is lower than the 26.23% yield obtained when the screw press was used [34], but higher than the 6.80% obtained using a hydraulic press. This higher yield may be attributed to the use of unpeeled seeds. Nut oils generally have higher extraction yields compared to seed oils. Yields of 31.2% for almond oil, 56% for walnut oil, and 28.6% for pistachio oil have previously been reported using a hydraulic press [34]. The extraction yield obtained in this study closely matched these values since similar extraction parameters and nut varieties were used. Hydraulic press extraction produced sufficiently high oil yields to justify its use in oil production, except for pumpkin seed oil, where alternative methods like screw press, supercritical fluid, or solvent extraction may be used to optimize extraction. Regarding oxidative stability, significant differences were found across the oils, with pumpkin seed oil showing the highest stability and chia seed oil the lowest. Chia seed oil's low oxidative stability is attributed to its high content of polyunsaturated fatty acids, which, despite the presence of antioxidant compounds, make it particularly susceptible to oxidation [30]. Among nuts, almond and pistachio oils exhibited similar stability values and were more stable than the seed oils. On the other hand, walnut oil's stability was like that of poppy oil, consistent with other studies reporting that walnut oil's stability ranges from 3.9 to 7.8 h depending on the crop type [35]. These differences arise from lipid composition since almonds and pistachios contain higher proportions of oleic acid (ranges of 57.5-78.7% and 54.2-81.17%, respectively) [36; 37]. The presence of a single cis-double bond in oleic acid makes this fatty acid less reactive in the presence of oxygen compared to polyunsaturated fatty acids that contain multiple double bonds [38]. Thus, oils with a higher oleic acid content tend to have longer shelf lives under storage and cooking conditions and would be more suitable for use in heat-exposed products like bricoche bread. Additionally, walnut oil is a source of polyunsaturated fatty acids [39], specifically linoleic acid (53.70-63.19%), thus presenting similar stability values to poppy oil. The oxidative stability of oils may impact the stability of the products to be developed, especially those that may be subjected to heat treatment. Viscosity is related to the processing and quality of oils, the level of saturation, and the triglyceride composition of the vegetable oil [34]. Chia seed and nut oils showed lower values with no significant differences, while pumpkin seed oil was the most viscous. In summary, the oil yields from pumpkin, chia, and melon seeds were lower than the reported values found in the literature primarily due to the type of press used. In this sense, to obtain higher yields, the use of screw presses or other alternative methods