ABSTRACT: Edible oil is oxidized during processing and storage via autoxidation photosensitized oxidation, in which triplet oxygen ( 3 O 2 ) singlet 1 react with the oil, respectively. Autoxidation of oils requires radical forms acylglycerols, whereas oxidation does not require lipid radicals since reacts directly double bonds. Lipid hydroperoxides formed by are conjugated dienes, produces both nonconjugated dienes. The decomposed to produce off‐flavor compounds quality decreases....

ABSTRACT: Antioxidants delay or inhibit lipid oxidation at low concentration. Tocopherols, ascorbic acid, carotenoids, flavonoids, amino acids, phospholipids, and sterols are natural antioxidants in foods. the of foods by scavenging free radicals, chelating prooxidative metals, quenching singlet oxygen photosensitizers, inactivating lipoxygenase. show interactions, such as synergism (tocopherols acids), antagonism (α‐tocopherol caffeic acid), simple addition. Synergism occurs when one...

ABSTRACT: Reactive oxygen species (ROS) is formed enzymatically, chemically, photochemically, and by irradiation of food. It also the decomposition inter-reactions ROS. The hydroxy radical most reactive ROS then followed singlet oxygen. Reactions with food components produce undesirable volatile compounds carcinogens, destroy essential nutrients, change functionalities proteins, lipids, carbohydrates. Lipid oxidation produces low-molecular-weight aldehydes, alcohols, hydrocarbons. causes...

ABSTRACT: Riboflavin is relatively stable during thermal and nonthermal food processing storage but very sensitive to light. It can accept or donate a pair of hydrogen atoms. act as photosensitizer (through either Type I II mechanism) prooxidant for components under Photosensitization riboflavin causes production reactive oxygen species such superoxide anion, singlet oxygen, hydroxy radical, peroxide. Radicals accelerate the decomposition proteins, lipids, carbohydrates, vitamins, could...

ABSTRACT: The formation of singlet oxygen by riboflavin and the kinetics mechanisms degradation in aqueous solution under light were determined. rate was 2.31 μmole oxygen/mL headspace/h serum bottle. degradations 66% D 2 O 40% H O, respectively, after 24 h. results indicate that is involved destruction light. destructions 94.0% 15.7% with 0 mM or 160 ascorbic acid, 96 reaction between 1.01 × 10 /M/s, which a diffusion‐controlled rate. This explains extremely fast foods Ascorbic acid sodium...

ABSTRACT: Effects of roasted sesame seed oil on the oxidative stability soybean during frying flour dough at 160 °C were studied by determining fatty acid composition and conjugated dienoic (CDA), p ‐anisidine (PA), free (FFA) values. Concentration in was 0%, 10%, 20%, or 30% (v/v). Tocopherols lignan compounds also determined high‐performance liquid chromatography. As number fryings performed increased, linolenic content decreased, decreasing rate lower containing than no oil. CDA FFA...

ABSTRACT: The characterization and quantification of anthocyanins in grape cultivars Oll‐Meoru ( Vitis coignetiae × labrusca ), Neut‐Meoru Muscal Bailey A. labruscana Campbell Early V. vinifera ) cultivated Korea were carried out by partial purification through XAD‐7 column chromatography followed C‐18 HPLC/diode array detector (DAD), HPLC/MS, HPLC/MS/MS analyses. oven temperature during the reverse phase HPLC greatly affected separation individual anthocyanins. result showed that optimum...

Abstract Seed roasting is practiced in the mustard oil industry some areas of world, and can affect physicochemical properties for further applications. This research studied differences oxidative stability, tocopherols, carotenoids during heating at 160 °C between extracted from roasted seeds that unroasted seeds. The content free fatty acids, polar compounds (PC), lutein were not significantly different seed oils before heating. acid compositions both also similar, with high amounts...

ABSTRACT: Soymilks with or without added riboflavin in serum bottles were stored under light dark at 20 °C. The headspace oxygen and volatile compounds determined by gas chromatography. Riboflavin had significant effects on the depletion formation soymilk ( P < 0.05). did not have of > increased light, but as increased. Storage temperature 4 °C difference effect light. Hexanal, an important beany flavor compound, was identified major compound photosensitized soymilk. Singlet oxidation...

Temperature dependence of the autoxidation perilla oil and tocopherol degradation was studied with corn as a reference. The oils were oxidized in dark at 20, 40, 60, 80 degrees C. Oil oxidation determined by peroxide conjugated dienoic acid values. Tocopherols quantified HPLC. both increased time temperature. Induction periods for decreased temperature, longer than oil, indicating higher sensitivity to oxidation. However, lag stability tocopherols oil. Activation energies (23.9 24.2, 9.8...

The addition of spinach (Spinacia oleracea) powder in flour dough as a natural antioxidant was investigated, and oxidation frying oil the lipid fried products during also studied. Flour with rolled into sheets 0.1 cm thickness then cut squares to be fried. Each performed 160 °C soybean for 1 min, repeated every 20 min h. Fried samples were analyzed immediately or after being stored at 60 12 days under dark. content lower powder. Spinach decreased accumulation polar compounds but had little...

ABSTRACT: Lignan compounds were extracted from roasted sesame oil and their effects on the autoxidation of methyl linoleate (ML) studied. oil, sesamol, sesamin, sesamolin, added to ML, which was then oxidized at 60 o C for 18 h in dark. Alpha‐tocopherol separately ML a reference antioxidant. Degree oxidation monitored by conjugated dienoic acid (CDA) contents p ‐anisidine value (PAV) AOCS methods, retention gas chromatography. CDA PAV samples increased with time dark, decreased. Sesamol‐,...

Effects of chlorophyll b, phosphatidylcholine (PC), and phosphatidylethanolamine (PE) on the oxidation canola oil under 1700 lux light at 10 degrees C were studied by determining headspace oxygen depletion peroxide value. Chlorophyll b increased via production singlet oxygen. PC PE did not affect formation in absence C; however, they presence chlorophyll, with higher effect than PE. was degraded during photooxidation decreased its photodecomposition protection There no or photooxidation. The...

ABSTRACT The effects of 0, 1.0, 2.0 and 4.0 (x 10 −3 M) α‐, γ‐ or δ‐tocopherol on chlorophyll b photosensitized oxidation soybean oil in methylene chloride were studied by peroxide values headspace oxygen. As concentrations tocopherols increased, decreased oxygen increased (P < 0.05). At 1.0 × M, α‐tocopherol showed highest antioxidant effect, γ‐tocopherol second then δ‐tocopherol. α‐ ‐γ‐Tocopherols had similar lower effect at M However, the three not different > 0.05) M. α‐Tocopherol...

ABSTRACT: Effects of sesame oil addition to soybean during frying on the lipid oxidative stability and antioxidants contents fried products storage in dark were studied. Flour dough pieces (2 cm × 2 0.1 cm) at 160 °C for 1 min oil-added oil. Concentrations 0%, 10%, 20% by volume. Fried put into a glass bottle, bottles tightly sealed stored 60 18 d. Lipid oxidation was determined fatty acid composition changes conjugated dienoic (CDA) p -anisidine (PA) values. Tocopherols lignan compounds...