beta-carotene and n-hexanal

Pumpkin seed and sunflower oil are rich in bioactive compounds, but are prone to oxidation during storage. Their fatty acids, carotenoid and volatile compounds and their Fourier-transform infrared (FTIR) profiles were studied during 8 months storage in order to assess the overall quality, but also to assess the impact of the oleogelation as conditioning process.. The fatty acids methyl esters were analyzed by gas chromatography-mass spectrometry (GC-MS). The linoleic acid was the most abundant in the oils (604.6 g kg. During 8 months storage, the decrease of polyunsaturated fatty acid total amount was 5.72% for the pumpkin seed oil and 3.55% for the oleogel, while in the sunflower oil samples of 2.93% and 3.28% for the oleogel. It was concluded that oleogelation might protect specific carotenoid compounds, since the oleogels displayed higher content of β-carotene at each storage time. Hexanal and heptanal were detected during storage, regardless of the oil or oleogel type. FTIR analysis depicts the differences in the constituent fatty acids resulting due to thermal oxidation or due to storage. © 2022 Society of Chemical Industry.

Topics: Aldehydes; beta Carotene; Carotenoids; Cucurbita; Fatty Acids; Plant Oils; Seeds; Sunflower Oil

Dee are a unique and rapidly growing part of the global snack food market and are recognised as having distinct sensory properties (taste and texture). In this study, the development of important volatile aroma compounds over storage was evaluated and their chemical origin explained. Sweet potatoes were batch fried in high oleic sunflower oil (HOSO) and subjected to accelerated shelf life testing. Headspace volatiles were analysed using SPME GC-MS and correlated with sensory perception. All the components (sweet potatoes, oil and β-carotene) showed significant degradation after 3 weeks of storage at accelerated conditions (equivalent to 12 weeks in real-time at 25 °C). Marker volatiles associated with lipid oxidation such as hexanal, octanal, pentanal were identified, in addition to norisoprenoids from β-carotene degradation such as β-ionon, 5,6-epoxy-β-ionone, dihydroactinidiolide (DHA) and β-cyclocitral. The most prominent marker of lipid oxidation (hexanal) rapidly increased at week 1, whereas the carotene degradation makers did not rapidly increase until week 3 suggesting a delayed response. The frying temperature during the batch frying process of SPC was also shown to play a significant role in the sensory perception of the product over the shelf life. Overall, the results suggest that tight control of process variables and raw material design may enable extended shelf life and potentially enhanced health credentials for the product. These findings are unique to SPC, but also of value to the wider food industry.

Topics: Aldehydes; Benzofurans; beta Carotene; Cooking; Diterpenes; Food Industry; Gas Chromatography-Mass Spectrometry; Hot Temperature; Ipomoea batatas; Lipid Metabolism; Lipids; Norisoprenoids; Odorants; Oxidation-Reduction; Sensation; Sunflower Oil; Taste; Volatile Organic Compounds

To evaluate the correlation between the commercial grade determined by organoleptic judgment panel and chemical substances in dried laver Porphyra spp., we analyzed the contents of free amino acids, 5'-nucleotides, total lipids, fatty acids, α-tocopherol, lipophilic pigments, and aldehydes in several grades of laver that had been classified by an organoleptic judgment panel. Compared with the lower-grade laver samples, the excellent-grade laver samples contained higher concentrations of free amino acids, 5'-nucleotides, total lipids, α-tocopherol, chlorophyll a, and β-carotene and lower concentrations of aldehydes such as 4-hydroxy-2-hexenal (HHE), propanal, butanal, and 1-hexanal, which are formed during lipid peroxidation of n-3 or n-6 polyunsaturated fatty acids. In addition, the HHE content was strongly correlated with the propanal content in the analyzed laver (r(2)=0.9123). These results showed that the commercial grade assigned by an organoleptic judgment panel was correlated with chemical substances associated with color, taste, and the prevention of lipid oxidation.

Topics: Aldehydes; alpha-Tocopherol; beta Carotene; Chlorophyll; Chlorophyll A; Fatty Acids; Lipid Metabolism; Lipid Peroxidation; Oxidation-Reduction; Porphyra

Oxidation in 3 types of bovine milk with different fatty acid profiles obtained through manipulation of feed was evaluated by analytical methods quantifying the content of potential antioxidants, the tendency of formation of free radicals, and the accumulation of primary and secondary oxidation products. The milk samples were evaluated in parallel by descriptive sensory analysis by a trained panel, and the correlation between the chemical analysis and the descriptive sensory analysis was evaluated. The fatty acid composition of the 3 types of milk was found to influence the oxidative and lipolytic changes occurring in the milk during chill storage for 4 d. Sensory analysis and chemical analysis showed high correlation between the typical descriptors for oxidation such as cardboard, metallic taste, and boiled milk and specific chemical markers for oxidation such as hexanal. Notably, primary oxidation products (i.e., lipid hydroperoxides) and even the tendency of formation of radicals as measured by electron spin resonance spectroscopy were also highly correlated to the sensory descriptors for oxidation. Electron spin resonance spectroscopy should accordingly be further explored as a routine method for detection of early events in lipid oxidation in milk to predict shelf-life.

Topics: Aldehydes; alpha-Tocopherol; Animal Feed; Animals; beta Carotene; Cattle; Cold Temperature; Electron Spin Resonance Spectroscopy; Fatty Acids; Fatty Acids, Nonesterified; Food Preservation; Humans; Lipid Peroxidation; Lipid Peroxides; Lipolysis; Milk; Oxidation-Reduction; Sensation; Thiobarbituric Acid Reactive Substances; Time Factors

Differences in the oxidative stability of milk from cows fed grass-clover silage or hay were examined in relation to fatty acid composition and contents of antioxidants and copper in the milk. The oxidation processes were induced by exposing the milk to fluorescent light. Protein oxidation was measured as an accumulation of dityrosine, whereas lipid oxidation was measured as an accumulation of lipid hydroperoxides as the primary oxidation product, and as the secondary oxidation products, pentanal, hexanal, and heptanal. No differences were found in the protein oxidation of the 2 types of milk measured as accumulation of dityrosine, but there was an increased accumulation of lipid hydroperoxides and hexanal in milk from cows fed grass-clover silage, compared with milk from cows fed hay. The higher degree of lipid oxidation in milk from cows fed grass-clover silage could not be explained from the concentration of alpha-tocopherol, carotenoids, uric acid, and copper in the milk. However, it was thought to be highly influenced by the significantly higher concentration of linolenic acid present in milk from cows fed grass-clover silage. A larger part of alpha-tocopherol and beta-carotene was transferred from the feed to the milk when cows were fed grass-clover silage than when cows were fed hay as roughage. The significantly higher concentration of polyunsaturated fatty acids in milk from cows fed grass-clover silage may be important for the better transfer of alpha-tocopherol from the feed to the milk. Other circumstances, as the different conditions in the rumen may also play a role, due to the different types of roughages and their digestibility, or be related to the mechanisms during milk production for the higher yielding cows fed grass-clover silage.

Topics: Aldehydes; alpha-Tocopherol; Animal Feed; Animals; Antioxidants; beta Carotene; Cattle; Copper; Fatty Acids; Female; Food Preservation; Gas Chromatography-Mass Spectrometry; Light; Lipid Peroxidation; Lipid Peroxides; Milk; Oxidation-Reduction; Riboflavin; Time Factors; Tyrosine; Volatilization

In patients with end-stage renal failure (ESRF), the incidence of atherosclerosis and cancer is increased. The importance of lipid peroxidation (LPO) products in the pathogenesis of these complications has recently been emphasized. The LPO products malondialdehyde (MDA) and hexanal, lipophilic antioxidants and erythrocyte glutathione (GSH) were estimated in 10 pediatric hemodialysis (HD) patients before and after HD and in 11 peritoneal dialysis (CPD) patients. Before HD, MDA was elevated [median (interquartile range): 384.5 (110 to 501) nM; normal < 150 nM], whereas plasma hexanal levels were normal in all patients [130.5 (88 to 222) nM; < 320 nM]. HD decreased MDA concentrations on average by 88% but did not change hexanal levels. CPD patients exhibited high plasma MDA concentrations [371 (287 to 468) nM], whereas hexanal was in the low normal range [56 (51 to 81) nM]. Antioxidants were normal in both groups and unchanged during HD. GSH decreased slightly during HD. We hypothesize that MDA may accumulate in ESRF due to reduced plasma clearance. Our results argue against a general increase of LPO in uremia.

Topics: Adolescent; Adult; Aldehydes; beta Carotene; Carotenoids; Child; Cryptoxanthins; Erythrocytes; Female; Glutathione; Humans; Lipid Metabolism; Lipid Peroxidation; Lipids; Lycopene; Male; Malondialdehyde; Peritoneal Dialysis; Renal Dialysis; Vitamin E; Xanthophylls