# Antioxidants
## 4 Discussion
In addition, the content of ALA in HO on day 7 was higher than in CO, demonstrating that the hemp extract reduced ALA oxidation. Unlike ALA, LA remained stable in both HO and CO. The most probable reason is that linolenate, having a higher degree of unsaturation, is more prone to oxidation than linoleate with 2.4-fold higher reactivity. Thus, linolenate is the first substrate hit by free radicals [9]. In contrast, EO exhibited completely different kinetics compared to CO and HO, starting from lipolysis. A strong hydrolysis of TAGs was followed by an increase in DAG and FFA content. Since the free PUFAs are much more prone to oxidation than their esterified counterparts [48], a severe worsening of the fatty acid composition took place in EO. Almost all FAMEs were affected by oxidation, with a drastic and significant reduction in ALA and even LA, underlining the more marked progress in oxidation. This pro-oxidant activity has been already described by the other researchers [33; 49; 50]. In fact, it was stated that many factors control the antioxidant or pro-oxidant effect of \(\alpha\)-tocopherol, namely, the nature of the substrate and its mobility within it, its concentration, and the applied conditions, such as the temperature and the potential interactions with other substances in the matrix [51]. Moreover, it has been suggested that, in oils, the most effective antioxidants are polar antioxidants and not nonpolar ones, which are more effective in protecting emulsions (the so-called \"polar paradox\") [52]. As expected, the protective effects of hemp infloresences against oxidation, as well as the pro-oxidant effect of \(\alpha\)-tocopherol, were established by primary and secondary oxidation products and the protection factor (Pf). According to [PERSON] [46], peroxide degradation takes place at very high temperatures, and this could be an explanation for the observed linear trend, since a moderate heating was applied in the experiment (40 \({}^{\circ}\)C). CO and HO were characterized, as expected, by a progress in hexanal formation that reflected the peroxide content. Thus, an increasing (CO) or constant (HO) trend in peroxide development led to an increasing (CO) or constant (HO) trend in hexanal formation. The trend of hexanal is also a reflection of ALA oxidation, since it is widely reported as a precursor [53]. Consequently, the progressive oxidation of ALA in CO resulted in a progressive increase in hexanal, while the stability of ALA in HO resulted in an unchanged hexanal content. On the other hand, a completely different process was observed in EO. In fact, despite reaching rancidity after only 2 days (50 meq O\({}_{2}\)/kg oil as the maximum value indicates that complete rancidity has been reached), the hexanal content remained unusually low. Other authors documented the same situation, stating that a higher concentration of \(\alpha\)-tocopherol led to a higher inhibition of hexanal formation [53; 54]. The authors suggested that this suppression is due to the action of \(\alpha\)-tocopherol on both peroxyl and alkoxyl radicals. On one hand, \(\alpha\)-tocopherol, competing with the lipid substrate, might donate its hydrogen atom to the alkoxyl radical, forming a more stable tocopheroxyl radical, which is then also able to trap the alkoxyl radical [54]. On the other hand, \(\alpha\)-tocopherol could act on peroxyl radicals by intercepting them and reducing the decomposition of peroxides and, consequently, the formation of hexanal [53]. The conjugated fatty acids were examined through GC-FID and not by measuring the absorbance because, as reported by [PERSON] et al. [16], the cannabinoids can interfere, leading to an overestimation of data. However, the sum of conjugated linoleic acids (CLAs) and conjugated linoleic acids (CLnAs) did not play an important role in the study, as their concentration was scarce and remained unchanged over time in all samples.