Influence of microwave roasting on positional distribution of fatty acids of triacylglycerols and phospholipids in sunflower seeds (Helianthus annuus L.)

Abstract

Influence of microwave roasting on positional distribution of fatty acids of triacylglycerols and phospholipids in sunflower seeds (Helianthus annuus L.)Whole sunflower seeds were exposed to microwave roasting for 6, 12, 20 or 30 min at a frequency of 2450 MHz. The kernels were then separated from the sunflower seeds, and the lipid components and the positional distribution of fatty acids in triacylglycerols (TAGs) and phospholipids (PLs) were investigated. Major lipid components were TAGs and PLs, while steryl esters, free fatty acids and diacylglycerols were also present in minor proportions. The greatest PL losses (p < 0.05) were observed in phosphatidyl ethanolamine, followed by phosphatidyl choline or phosphatidyl inositol. Significant differences (p < 0.05) in fatty acid distributions occurred (with few exceptions) when sunflower seeds were microwaved for 20 min or more. Nevertheless, the principal characteristics for the positional distribution of fatty acids still remained after 20 min of microwave roasting; unsaturated fatty acids, especially linoleic, were predominantly concentrated in the sn-2-position and saturated fatty acids, especially stearic and palmitic acids, primarily occupied the sn-1-or sn-3-position. These results indicate that no significant changes in fatty acid distribution of TAGs and PLs would occur within 12 min of microwave roasting, ensuring that a good-quality product would be attained.

Microwave roasting effects on the physico‐chemical composition and oxidative stability of sunflower seed oil

“…The longer the roasting time, the greater was the loss in weight of the seeds. This trend agreed with the findings of Yoshida et al (2,4), who reported the loss in weight of sunflower seeds. This loss in weight may reflect total volatile substances, but it was considered to be mostly due to the loss of moisture.…”

“…This loss in weight may reflect total volatile substances, but it was considered to be mostly due to the loss of moisture. In the present analysis, the loss in weight of sunflower oilseeds was found to be greater as compared with those reported by Yoshida et al (2), which might be attributable to variations in the genetic makeup and the original moisture contents of the varieties of sunflower oil seeds investigated. Yoshida and Kojimoto (9) and Yoshida et al (3,5) reported that after roasting for different times, changes in the weight of peanut and sesame seeds may be due to the presence of moisture and volatile components.…”

“…However, Jung et al (32) reported that the iodine values of red pepper seed oils did not change with roasting time. In sunflower seed and peanut oils, Yoshida et al (2,33) found that roasting caused a significant decrease (P < 0.05) in molecular species containing more than four double bonds.…”

Microwave roasting effects on the physico‐chemical composition and oxidative stability of sunflower seed oil

“…The longer the roasting time, the greater was the loss in weight of the seeds. This trend agreed with the findings of Yoshida et al (2,4), who reported the loss in weight of sunflower seeds. This loss in weight may reflect total volatile substances, but it was considered to be mostly due to the loss of moisture.…”

“…This loss in weight may reflect total volatile substances, but it was considered to be mostly due to the loss of moisture. In the present analysis, the loss in weight of sunflower oilseeds was found to be greater as compared with those reported by Yoshida et al (2), which might be attributable to variations in the genetic makeup and the original moisture contents of the varieties of sunflower oil seeds investigated. Yoshida and Kojimoto (9) and Yoshida et al (3,5) reported that after roasting for different times, changes in the weight of peanut and sesame seeds may be due to the presence of moisture and volatile components.…”

“…However, Jung et al (32) reported that the iodine values of red pepper seed oils did not change with roasting time. In sunflower seed and peanut oils, Yoshida et al (2,33) found that roasting caused a significant decrease (P < 0.05) in molecular species containing more than four double bonds.…”

Effects of Seed Roasting Temperature on Sesame Oil Fatty Acid Composition, Lignan, Sterol and Tocopherol Contents, Oxidative Stability and Antioxidant Potential for Food Applications

“…As has been reported in the literature, 97% of the tocopherol in sesame oil was in the γ-form [ 3 ]. USSO contained 25.9 mg/100 g; this quantity was in close agreement with the values previously reported [ 29 , 32 ]. After heat treatment, it was reduced to 23.2 mg/100 g. The higher loss (10.6%) occurred when sesame seeds were roasted at 250 °C ( Table 4 ).…”

Fatty acid distributions of triacylglycerols and phospholipids in peanut seeds (Arachis hypogaea L.) following microwave treatment

“…PC was detected as the dominant component, followed by PI or PE. The proportion of the three PLs differed from that typically reported in those of sesame seeds (Yen et al, 1986) or sunflower kernels (Yoshida et al, 2001), possibly because of varietal tissue. The greatest rate of PL losses (Po0:05) was observed for PE, followed by PC or PI.…”

Microwave roasting effects on the physico‐chemical composition and oxidative stability of sunflower seed oil

“…The longer the roasting time, the greater was the loss in weight of the seeds. This trend agreed with the findings of Yoshida et al (2,4), who reported the loss in weight of sunflower seeds. This loss in weight may reflect total volatile substances, but it was considered to be mostly due to the loss of moisture.…”

“…This loss in weight may reflect total volatile substances, but it was considered to be mostly due to the loss of moisture. In the present analysis, the loss in weight of sunflower oilseeds was found to be greater as compared with those reported by Yoshida et al (2), which might be attributable to variations in the genetic makeup and the original moisture contents of the varieties of sunflower oil seeds investigated. Yoshida and Kojimoto (9) and Yoshida et al (3,5) reported that after roasting for different times, changes in the weight of peanut and sesame seeds may be due to the presence of moisture and volatile components.…”

“…However, Jung et al (32) reported that the iodine values of red pepper seed oils did not change with roasting time. In sunflower seed and peanut oils, Yoshida et al (2,33) found that roasting caused a significant decrease (P < 0.05) in molecular species containing more than four double bonds.…”

Effects of Seed Roasting Temperature on Sesame Oil Fatty Acid Composition, Lignan, Sterol and Tocopherol Contents, Oxidative Stability and Antioxidant Potential for Food Applications

“…As has been reported in the literature, 97% of the tocopherol in sesame oil was in the γ-form [ 3 ]. USSO contained 25.9 mg/100 g; this quantity was in close agreement with the values previously reported [ 29 , 32 ]. After heat treatment, it was reduced to 23.2 mg/100 g. The higher loss (10.6%) occurred when sesame seeds were roasted at 250 °C ( Table 4 ).…”

Fatty acid distributions of triacylglycerols and phospholipids in peanut seeds (Arachis hypogaea L.) following microwave treatment

“…PC was detected as the dominant component, followed by PI or PE. The proportion of the three PLs differed from that typically reported in those of sesame seeds (Yen et al, 1986) or sunflower kernels (Yoshida et al, 2001), possibly because of varietal tissue. The greatest rate of PL losses (Po0:05) was observed for PE, followed by PC or PI.…”

Microwave roasting effects on the physico‐chemical composition and oxidative stability of sunflower seed oil

“…The longer the roasting time, the greater was the loss in weight of the seeds. This trend agreed with the findings of Yoshida et al (2,4), who reported the loss in weight of sunflower seeds. This loss in weight may reflect total volatile substances, but it was considered to be mostly due to the loss of moisture.…”

“…This loss in weight may reflect total volatile substances, but it was considered to be mostly due to the loss of moisture. In the present analysis, the loss in weight of sunflower oilseeds was found to be greater as compared with those reported by Yoshida et al (2), which might be attributable to variations in the genetic makeup and the original moisture contents of the varieties of sunflower oil seeds investigated. Yoshida and Kojimoto (9) and Yoshida et al (3,5) reported that after roasting for different times, changes in the weight of peanut and sesame seeds may be due to the presence of moisture and volatile components.…”

“…However, Jung et al (32) reported that the iodine values of red pepper seed oils did not change with roasting time. In sunflower seed and peanut oils, Yoshida et al (2,33) found that roasting caused a significant decrease (P < 0.05) in molecular species containing more than four double bonds.…”

Effects of Seed Roasting Temperature on Sesame Oil Fatty Acid Composition, Lignan, Sterol and Tocopherol Contents, Oxidative Stability and Antioxidant Potential for Food Applications

“…As has been reported in the literature, 97% of the tocopherol in sesame oil was in the γ-form [ 3 ]. USSO contained 25.9 mg/100 g; this quantity was in close agreement with the values previously reported [ 29 , 32 ]. After heat treatment, it was reduced to 23.2 mg/100 g. The higher loss (10.6%) occurred when sesame seeds were roasted at 250 °C ( Table 4 ).…”

Fatty acid distributions of triacylglycerols and phospholipids in peanut seeds (Arachis hypogaea L.) following microwave treatment

“…PC was detected as the dominant component, followed by PI or PE. The proportion of the three PLs differed from that typically reported in those of sesame seeds (Yen et al, 1986) or sunflower kernels (Yoshida et al, 2001), possibly because of varietal tissue. The greatest rate of PL losses (Po0:05) was observed for PE, followed by PC or PI.…”