Oxidative stabilities of olive and camellia oils: Possible mechanism of aldehydes formation in oleic acid triglyceride at high temperature

Effects of different preheat treatments on volatile compounds of camellia ( Camellia oleifera Abel .) seed oil and formation mechanism of key aroma compounds

“…Subsequently, four kinds of free radicals reacted with O2 to form the corresponding peroxy radical (ROO▪) and further formed four kinds of oleic acid hydroperoxides. Among them, 10‐OOH can be pyrolyzed to nonanal, 11‐OOH can be pyrolyzed to octanal, and 9‐OOH can be pyrolyzed to nonanal and (E)‐2‐decenal (Cao et al., 2020).…”

“…As such, the proportion of oxidation products of oleic acid at different temperatures was different, consistent with the research of Cao et al that oleic acid in tea oil mainly formed 10‐OOH and pyrolyzed to nonanal, followed by 11‐OOH pyrolysis to form octanal, and finally formed 9‐OOH and pyrolysis to form trans‐2‐decenal. However, at 150℃ and 180℃, the relative content of nonanal and octanal was decreased, whereas the content of (E)‐2‐decenal changed little (Cao et al., 2020).…”

Fingerprinting triacylglycerols and aldehydes as identity and thermal stability indicators of camellia oil through chemometric comparison with olive oil

“…A prominent feature of aldehyde heatmap (Figure 5m) is that the clustering of aldehydes is largely based on their fatty acid precursors. Among the aldehydes that increased continuously at 185°C (cluster B in Figure 5m), 2‐undecenal (X), 2‐decenal (IX), and octanal (V) mainly originate from the hemolytic β ‐scission of 8‐, 9‐, and 11‐hydroperoxides of oleic acid, respectively (Cao et al., 2020; Ho & Chen, 1994), while 2‐nonenal (VI) might from further decomposition of 2‐undecenal (Warner et al., 2001). Among the aldehydes that peaked within 2 hr of 185°C heating in VOO (cluster A in Figure 5m), 2,4‐decadienal (VIII) and 2‐octenal (IV) are the known breakdown products of linoleic acid and trilinolein (Choe & Min, 2006; Warner et al., 2001) while 2,4‐heptadienal (II) is the oxidation products of α‐linolenic acid (Guillén & Uriarte, 2012; Ho & Chen, 1994).…”

“…This feature of fatty acid composition is expected to affect the thermal stability of camellia oil. (Cao et al, 2020;Karakaya & Şimşek, 2011).…”

“…Among the aldehydes that peaked within 2 hr of 185°C heating in VOO (cluster A in Figure 5m), 2,4-decadienal (VIII) and 2-octenal (IV) are the known breakdown products of linoleic acid and trilinolein (Choe & Min, 2006;Warner et al, 2001) while 2,4-heptadienal (II) is the oxidation products of α-linolenic acid (Guillén & Uriarte, 2012;Ho & Chen, 1994). Interestingly, nonanal (VII) has been shown as a degradation product from oleic acid (Cao et al, 2020;Guillén & Uriarte, 2012), but its formation pattern was more comparable to the aldehydes degraded from linoleic acid, such as 2,4-decadienal (VIII) and 2-octenal (IV), than the ones from oleic acid. The association between aldehyde formation and fatty acid composition is also supported by our study on the aldehyde formation in soybean oil (Wang, Csallany, et al, 2016 (Wang, Csallany, et al, 2016).…”