## 3 Results
### Results and Evaluation of FTIR Spectra
Thus, apart from the omega-6 LA, other essential omega-3 and omega-6 fatty acids were undetectable, the ratio between them incalculable and therefore cannot be analyzed. Of the saturated fatty acids, stearic acid or C18:0 was found in higher content in the FFA of the TAC extracts from both the juice and the by-products (70.4 \(\pm\) 0.8% and 66.2 \(\pm\) 5.4% respectively), followed by palmitic acid or C16:0 (22.4 \(\pm\) 0.5% and 25.5 \(\pm\) 5.05%). With respect to the composition of esterified fatty acids in polar lipids PL for the TAC extracts of both apple juice and its by-products, it is observed that saturated fatty acids, much higher amounts of unsaturated fatty acids, UFAs, were detected than the FFA for the same samples, with contents of 40.9 \(\pm\) 0.7% and 26.7 \(\pm\) 0.5% for the FA in the PL of juice and pomace, respectively. SFAs again were found to be slightly higher (59.1 \(\pm\) 0.7%) in the PLs of the apple juice than their UFAs, but also in the PLs of apple pomace (73.4 \(\pm\) 0.5%), respectively, with palmitic acid C16:0 (33.03 \(\pm\) 0.65% and 35.14 \(\pm\) 0.14%) and stearic acid C18:0 (23.3 \(\pm\) 0.9% and 35.95 \(\pm\) 0.36%) being again the most abundant SFAs in the PLs of both juice and pomace, respectively. The UFAs of apple juice PLs consist mainly of polyunsaturated fatty acids (PUFA), with a content of 33.1 \(\pm\) 0.5% compared to MUFA (7.9 \(\pm\) 0.2%). Oleic acid (C18:1 c9) is the main representative MUFA with a content of 6.9 \(\pm\) 0.26%, while lower amounts of palmitoleic acid (C16:1 c9) of 1 \(\pm\) 0.1% were also detected. Within the PUFA, higher content of the omega-6 PUFA were detected than the omega-3 ones, with linoleic acid (LA) (26.9 \(\pm\) 0.4%) and alpha linolenic acid (ALA) (5.7 \(\pm\) 0.09%) being the most abundant in these two categories of PUFA, respectively. Similarly, the UFA of apple pomace PL are composed mainly of PUFA with a content of 19.4 \(\pm\) 0.7% compared to MUFA, which are less than half (7.3 \(\pm\) 0.3%). MUFAs are mainly composed of oleic acid with a content of 6.3 \(\pm\) 0.3%, while small amounts of gadoleic acid (C20:1) were also detected. Again, higher content of the omega-6 PUFA were detected (17.5 \(\pm\) 0.6%) compared to that of the omega-3 ones (1.9 \(\pm\) 0.08%). Again LA (17.2 \(\pm\) 0.6%) and ALA (1.9 \(\pm\) 0.09%) being the most abundant in these two categories of PUFA, respectively. Nevertheless, the omega-6/omega-3 PUFA ratio was approximately 5:1 for the PL in the TAC of apple juice and 9:1 for the PL in the TAC of apple pomace, respectively, with both these values being lower than the limit (>15:1) observed mainly in unhealthy processed Western-style foods. It should also be stressed out that the lower the value of this ratio in a food source or extract the stronger the anti-inflammatory potency for this sample and thus the merrier the health-promoting effects against inflammation and associated chronic diseases [25]. These results are comparable to the relative previously reported outcomes for the PL in TAC extracts from either other apple varieties and/or when different extraction processes were used, with, however, slightly lower UFA and higher SFA contents, as well as higher levels of the omega-6/omega-3 PUFA ratios [9; 10; 16]. Such differences seem to be related to the apple variety processed or due to the different methodology applied and solvents used. The presence of omega-3 PUFA in the PL of apple juice and by-products has been shown to have positive health benefits. Among the components of a healthy diet, omega-3 fatty acid intake is associated with reduced inflammation, especially when these PUFA are bound in PLs.