Effect of α-, γ-, and δ-tocopherol on the distribution of volatile secondary oxidation products in fish oil

Abstract

The relative ability of α‐, γ‐ and δ‐tocopherol (TOH) to influence the distribution of volatile secondary oxidation products in fish oil was studied, with particular emphasis on oxidation products expected to be important for adverse flavour formation. Purified fish oil samples with 100 ppm or 1000 ppm of the different tocopherols were analysed by dynamic headspace analysis of the volatiles formed after 2, 5 and 8 d of storage at 30 �C. The tocopherol type and concentration affected not only the overall formation of volatile secondary oxidation products, but also the composition of this group of oxidation products. Principal component analysis of the data obtained suggested that high tocopherol hydrogen‐donating power, i.e. a high tocopherol concentration or the use of αTOH as opposed to γTOH or δTOH, directs the formation of hydrocarbons, unsaturated carbonyl compounds of relatively high molecular weight, as well as the formation of cis, trans isomers of unsaturated aldehydes. Although an active inhibitor of overall volatile formation, αTOH at a high concentration thus appears to direct the formation of the more flavour‐potent aldehydes, such as those linking the carbonyl group with ethylenic conjugated unsaturation.

Fatty acid composition and tocopherol content of processed marine fish and contribution of omega-3 fatty acids

“…In contrast, the tocopherol content of fried Indian mackerel and rainbow sardine increased significantly, which could be because of the coconut oil and other ingredients added for marination particularly turmeric powder. Our results agreed with those obtained by Kulas et al (2002), which showed that the total tocopherol content varied in raw and cooked fish. In our results, tocopherol content was low in all curried and fried fish except Indian mackerel and rainbow sardine (Fig.…”

Fatty acid composition and tocopherol content of processed marine fish and contribution of omega-3 fatty acids

“…In contrast, the tocopherol content of fried Indian mackerel and rainbow sardine increased significantly, which could be because of the coconut oil and other ingredients added for marination particularly turmeric powder. Our results agreed with those obtained by Kulas et al (2002), which showed that the total tocopherol content varied in raw and cooked fish. In our results, tocopherol content was low in all curried and fried fish except Indian mackerel and rainbow sardine (Fig.…”

Scientific Opinion on Fish Oil for Human Consumption. Food Hygiene, including Rancidity

“…This compound can be formed during oxidation of oils and does not require high temperatures for its formation like the 4-hydroxyalkenals do. This compound was found in half of the studies (4 out of 8) on volatile oxidation compounds identified in oxidised fish oil reported in the literature ( ( Rørbaek 1994;MacFarlane et al, 2001;Kulås et al 2002;Karahadian and Lindsay 1989;Lee et al 2003;Hsieh et al, 1989;Olsen et al, 2005;Horuichi et al, 1998)). Only one of the four studies had quantified the concentration of the volatiles.…”

Application of natural antioxidants in the oxidative stabilization of fish oils: A mini‐review

“…A study (Zuta et al, 2007) assessing effects of different α‐tocopherol concentrations (50, 100, 250 to 500 ppm) in mackerel oil kept at different temperatures showed all the concentrations to produce antioxidative effects, the lower concentrations (50 and 100 ppm) being most effective and the effectiveness of higher concentrations (250 to 500 ppm) being much lower. Similar results were reported for fish oil kept at 30°C (Kul & Ackman, 2001; Kulås et al, 2002) and at 20°C in combination with other vitamin E isomers (Drusch et al, 2008).…”

Fatty acid composition and tocopherol content of processed marine fish and contribution of omega-3 fatty acids

“…In contrast, the tocopherol content of fried Indian mackerel and rainbow sardine increased significantly, which could be because of the coconut oil and other ingredients added for marination particularly turmeric powder. Our results agreed with those obtained by Kulas et al (2002), which showed that the total tocopherol content varied in raw and cooked fish. In our results, tocopherol content was low in all curried and fried fish except Indian mackerel and rainbow sardine (Fig.…”

Scientific Opinion on Fish Oil for Human Consumption. Food Hygiene, including Rancidity

“…This compound can be formed during oxidation of oils and does not require high temperatures for its formation like the 4-hydroxyalkenals do. This compound was found in half of the studies (4 out of 8) on volatile oxidation compounds identified in oxidised fish oil reported in the literature ( ( Rørbaek 1994;MacFarlane et al, 2001;Kulås et al 2002;Karahadian and Lindsay 1989;Lee et al 2003;Hsieh et al, 1989;Olsen et al, 2005;Horuichi et al, 1998)). Only one of the four studies had quantified the concentration of the volatiles.…”

Application of natural antioxidants in the oxidative stabilization of fish oils: A mini‐review

“…A study (Zuta et al, 2007) assessing effects of different α‐tocopherol concentrations (50, 100, 250 to 500 ppm) in mackerel oil kept at different temperatures showed all the concentrations to produce antioxidative effects, the lower concentrations (50 and 100 ppm) being most effective and the effectiveness of higher concentrations (250 to 500 ppm) being much lower. Similar results were reported for fish oil kept at 30°C (Kul & Ackman, 2001; Kulås et al, 2002) and at 20°C in combination with other vitamin E isomers (Drusch et al, 2008).…”

Fatty acid composition and tocopherol content of processed marine fish and contribution of omega-3 fatty acids

“…In contrast, the tocopherol content of fried Indian mackerel and rainbow sardine increased significantly, which could be because of the coconut oil and other ingredients added for marination particularly turmeric powder. Our results agreed with those obtained by Kulas et al (2002), which showed that the total tocopherol content varied in raw and cooked fish. In our results, tocopherol content was low in all curried and fried fish except Indian mackerel and rainbow sardine (Fig.…”

Scientific Opinion on Fish Oil for Human Consumption. Food Hygiene, including Rancidity

“…This compound can be formed during oxidation of oils and does not require high temperatures for its formation like the 4-hydroxyalkenals do. This compound was found in half of the studies (4 out of 8) on volatile oxidation compounds identified in oxidised fish oil reported in the literature ( ( Rørbaek 1994;MacFarlane et al, 2001;Kulås et al 2002;Karahadian and Lindsay 1989;Lee et al 2003;Hsieh et al, 1989;Olsen et al, 2005;Horuichi et al, 1998)). Only one of the four studies had quantified the concentration of the volatiles.…”

Application of natural antioxidants in the oxidative stabilization of fish oils: A mini‐review

“…A study (Zuta et al, 2007) assessing effects of different α‐tocopherol concentrations (50, 100, 250 to 500 ppm) in mackerel oil kept at different temperatures showed all the concentrations to produce antioxidative effects, the lower concentrations (50 and 100 ppm) being most effective and the effectiveness of higher concentrations (250 to 500 ppm) being much lower. Similar results were reported for fish oil kept at 30°C (Kul & Ackman, 2001; Kulås et al, 2002) and at 20°C in combination with other vitamin E isomers (Drusch et al, 2008).…”