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Lipid oxidation is a spontaneous process in fats and, consequently, in products with significant fat content. Many cosmetics fall into this category, presenting an intrinsic relationship between the productʼs quality, oxidation capacity, and market value. This study comprehensively investigated the aging of body lotions, accentuating the role of their chemical formulations. Sensory analysis clarified that controlled temperature-induced aging significantly altered the lotions' appearance, texture, color, and, to a lesser extent, odor, hinting at the onset of rancidity. As lipid peroxidation unfolds, the emergence of secondary oxidation products like aldehydes, ketones, and alcohols becomes prominent. These secondary products indicate a potential degradation in the lotion's quality and efficacy. Quantifying the primary oxidation products was possible using methods like the quantification of Conjugated Dienes (CD) expressed in percentage and the Peroxide Index (PI) method expressed in meqO 2 /kg of a dry sample. On the other hand, methods such as the p-Anidisine Index (pAi) and the thiobarbituric acid reactive substances (TBARS) with malonaldehyde (MDA) expressed as malonaldehyde concentration (mg/g of dry sample) provided the quantification of secondary oxidation products. Regarding lipid oxidation, lotions containing sunflower and soybean oils emerged as notably susceptible. Conversely, samples that demonstrated minimal oxidation, were attributed to protective elements such as Aloe barbadensis and Calendula officinalis extracts. Examining into secondary oxidation, four samples displayed the highest TOTOX values, indicating extensive oxidation. A discernible correlation was observed between TOTOX values and natural extracts' presence (or lack), underscoring their protective or exacerbating roles. Certain natural ingredients, including A. barbadensis leaf juice powder and C. officinalis flower extract, were recognized as supporters against oxidation. Yet, components like PEG-40 hydrogenated castor oil can, paradoxically, seem to intensify the oxidative cascade. This research provides crucial insights into the interplay between natural extracts and lipid oxidation in body lotions. The elucidated results accentuate the necessity for judicious ingredient selection, balancing the inclusion of natural extracts to ensure product quality, longevity, and safety. [Display omitted] • Aloe barbadensis and Calendula officinalis extracts show protection against oxidation. • PEG-40 hydrogenated castor oil accelerates lipid oxidation acting as a pro-oxidant. • Accelerated aging tests show changes in lotion appearance, texture, color, and odor. • Sunflower and soybean oils exhibited heightened vulnerability to lipid oxidation. • A correlation between TOTOX values and antioxidant-rich natural extracts emerged. [ABSTRACT FROM AUTHOR]

Lipid oxidation has an impact on the quality and properties of fat‐containing products that are commonly produced by cosmetics or coatings industries. In this study, a water‐in‐oil‐in‐water emulsion (48% w/w of pre‐polymerized linseed oil stabilized with alkylpolyglucoside) was subjected to oxidation under accelerated aging conditions at 50°C over 15 days. After fat extraction from emulsion, peroxide, and p‐anisidine values were measured using standardized methods. The application of near infrared spectroscopy (NIRS) in conjunction with chemometrics was investigated to assess the quality parameters of emulsions under accelerated aging within closed flasks. Significant variations were observed across the following spectral regions: 7541–5948, 5739–3657, and 3645–3637 cm−1. Partial least squares regression discriminant analysis, possibly combined with multiplicative scattering correction preprocessing, proved to be a powerful method to classify the emulsions according to two oxidation levels defined by periods A and B. The performances of the prediction model were characterized by a precision of 85%, a predictive value of period A of 98%, a sensitivity of 99%, a specificity of 81%, and an accuracy of 90%. Thus, we demonstrate that NIRS is a suitable analytical method to discriminate emulsions according to their aging behavior. Practical Applications: The PLS‐DA method coupled to near infrared spectroscopy analyses is adapted to assess the chemical degradations of vegetable oil–based emulsions due to lipid oxidation. This tool is interesting for at‐line or off‐line monitoring of emulsions during their storage. As it is a fast and nondestructive method, the quality control of a formulation stored in a closed glass container is facilitated. This method could also be used to determine the effectiveness of an antioxidant or a drier in emulsions, respectively, prepared for cosmetics and coatings. [ABSTRACT FROM AUTHOR]

Lipid oxidation deteriorates the sensory and nutritional quality of food emulsions containing polyunsaturated fatty acids. Classically, different extraction solvents are used as a first step to measure lipid oxidation in emulsions. However, it is unclear how the applied extraction method influences the measured lipid oxidation values. In this work, we systematically examined the performance of common solvent mixtures such as chloroform, methanol, and hexane (or isooctane)–isopropanol on lipid extraction from emulsions stabilized with different emulsifiers (Tween 20 (T20), whey proteins, and pea proteins) and oxidation levels, and how this, in turn, affected the measured hydroperoxide concentrations. Chloroform–methanol was the most effective solvent (lipid yield >93 wt.%). When using hexane–isopropanol, extraction yields were consistently high for T20‐ and pea protein‐based emulsions (>60 wt.%), but in whey protein‐based emulsions, values as low as 26 wt.% were measured. In case of incomplete extraction, hydroperoxide concentrations measured by colorimetric methods need to be corrected for this effect. When using 1H NMR to assess lipid oxidation, the actual amount of extracted lipids is intrinsically taken into account. This highlights not only the importance of the extraction method in determining lipid oxidation in emulsions but also that of the actual analysis method. Practical application: This study highlights that the lipid extraction yield can vary depending not only on the emulsion composition (e.g., type of emulsifier) but also on the oxidative state of the emulsion and the extraction solvent used. If this is overlooked, errors can be made in the hydroperoxide determination. Although these effects can be corrected for, this is not standard procedure, which implies that awareness on this matter should be increased. It is also important to point out that depending on the solvent used, the different lipid classes (including various lipid oxidation products) may be extracted at different levels. Chloroform–methanol should be preferred for extraction of all lipid and lipid oxidation‐derived molecules, including aldehydes. [ABSTRACT FROM AUTHOR]

Health concerns regarding fat consumption, as well as shifts in customer preference, have prompted substantial studies into low‐fat products. This study examined the nutritional, color, functional, and antioxidant properties of Bambara groundnut (BGN) flour varieties (cream, brown, and red‐coated) grains as well as their influence on the physicochemical properties, lipid oxidation, and sensory acceptability of low‐fat mutton patties. The patties were formulated with 2.5%, 5%, 7.5%, and 10% of BGN flour for each variety, and 100% mutton patties were used as a control. The BGN flours showed significant (p <.05) differences in their nutritional composition (except for ash content), color, functional (excluding emulsion stability), and antioxidant properties. The increase in the percentage of substitution of BGN flours significantly increased the fiber (0.00% to 0.79%), ash (1.16% to 1.99%), and carbohydrates (2.14% to 1.99%) contents of the formulated mutton patties. However, moisture and protein contents decreased. The cooking yield of the formulated patties significantly increased with the increase in the percentage substitution of BGN flours (2.5%–10%), with values ranging from 76.39% to 86.80%, but the diameter reduction was limited. The increase in the inclusion of BGN flours significantly increased the lightness, hue angle, color difference, and whiteness of patties. Nevertheless, the redness, yellowness, chroma, and yellowness index of the patties decreased. The hardness and resilience of formulated patties significantly increased, with values varying from 16.41 to 17.66 N, and from 0.35 to 0.48 J/J, respectively, whereas the springiness, cohesiveness, and chewiness decreased. The lipid oxidation of formulated mutton patties significantly increased from Days 7 to 21, but was still less than that of the control sample within storage days. The sensory properties of formulated patties were not significantly different from the control sample and were above the acceptable score of five. All BGN varieties had positive effects on the mutton patties, more especially red, followed by brown, and cream, respectively. The inclusion of a 10% red BGN flour variety is highly recommended due to its significant impact on mutton patties. Nevertheless, different types of BGN varieties can each be used as additives in mutton patties without having detrimental effects on the quality parameters of the patties. [ABSTRACT FROM AUTHOR]

Lipid oxidation in emulsions is hypothesised to increase with decreasing droplet size, as this increases the specific oil–water interfacial area, where lipid oxidation is expected to be initiated. In literature, however, contradictory results have been reported, which can be caused by confounding factors such as the oil droplet polydispersity and the distribution of components between the available phases. In this work, monodisperse surfactant-stabilised emulsions with highly controlled droplet sizes of 4.7, 9.1, and 26 µm were produced by microfluidic emulsification. We show that lipid oxidation increases with decreasing droplet size, which we ascribe to the increased contact area between lipids and continuous phase prooxidants. Besides, a significant amount of oxygen was consumed by oxidation of the surfactant itself (Tween 20), an effect that also increased with decreasing droplet size. These insights substantiate the importance of controlling droplet size for improving the oxidative stability of emulsions. [ABSTRACT FROM AUTHOR]

This research investigates the effects of using rosehip infusion as a marinade on the physicochemical, technological, textural properties, and oxidative stability of turkey breast meat. The chemical composition, technological properties, color and textural parameters, pH, and lipid oxidation of marinated turkey samples were determined. Marinades used in reformulated groups were prepared with rosehip at different concentrations (10 g (R1), 15 g (R2), and 20 g (R3)/150 mL). Rosehip-infused marinated samples exhibited lower pH, altered color parameters, enhanced water holding capacity and cooking yield, and increased marinade uptake (especially in R3). In texture analysis, it was observed that the hardness of the samples decreased, while the values of cohesiveness and springiness increased. Notably, rosehip infusion demonstrated antioxidative effects, lowering TBARS values compared to the control. In summary, marination with rosehip infusion presents a promising method to improve the technological and textural qualities of turkey breast meat while protecting against lipid oxidation. [ABSTRACT FROM AUTHOR]

Summary: This study aimed to determine differences in protein and lipid oxidation between bacon with KCl and calcium ascorbate (alternative) and with NaCl (traditional) during a two‐month storage process. At the beginning of storage, the carbonyl content and thiobarbituric acid reactive substances (TBARS) in alternative salt bacon were higher than those in traditional bacon, while the sulphhydryl content, fluorescence intensity and the α‐helix structure of alternative salt bacon protein were lower than those of traditional bacon. As the duration of storage progressed from 0 to 60 days, the degree of oxidation of proteins and fats in both groups of bacon increased, and the degree of oxidation of alternative salt bacon was stronger than that of traditional bacon. The results indicated that alternative salts can promote physicochemical changes in bacon to some extent. The changes in the protein and lipid oxidation of the two kinds of bacon during storage may led to the production of key volatile flavour substances and taste substances, which require further investigation. [ABSTRACT FROM AUTHOR]

Summary: Lipid oxidation is a major concern in preserving fish and its products, as it affects their quality, shelf life, and consumer acceptance. Cold plasma technology has emerged as a promising method for extending the shelf life of perishable products, including fish. However, the impact of cold plasma on lipid oxidation remains uncertain, as studies have reported conflicting findings. This review provides an up‐to‐date overview of the effects of cold plasma treatment on lipid oxidation in fish and fish‐based products, synthesising existing literature in the field. A comprehensive analysis of factors such as plasma generation techniques, treatment parameters, fish species, and lipid composition is conducted to elucidate the observed discrepancies in outcomes. In conclusion, current research suggests that moderate oxidation does not have adverse effects on overall sensory quality and may even enhance the flavour of fish. The degree of oxidation can be controlled through plasma parameters, thereby improving the quality of fish and fish products. [ABSTRACT FROM AUTHOR]

Infant follow‐on formulas (IFF) mimic human milk. This study aimed to identify the key structural levers that influence oxidative stability of IFF. Representative model IFF of marketed products in term of lipid composition were formulated with varying droplet size, lipid droplet core composition, and interfacial composition using different emulsifiers (soy lecithin or dairy phospholipids [DPL]). The oxidative stability of model IFF was assessed in accelerated storage conditions. No significant stabilization effect based on the lipid droplet core composition was observed. However, the nature of the interface, influenced by the emulsifier type, had an impact. Model IFF with DPL showed no loss of tocopherols and peroxide value was up to twice lower than those with soy lecithin after 20 days. This effect was particularly pronounced for the 0.4µm droplets. These results suggest that model IFF with DPL had a greater oxidative stability, likely due to the presence of sphingomyelin and the formation of a rigidified domain at the droplet surface. Model IFF with 0.4 µm droplets stabilized with soy lecithin, especially when added to the water phase, showed a tocopherols loss twice as high as that of IFF with DPL. These results indicate that oxidative stability of IFF is more influenced by the chemical environment rather than droplet size. Practical Application: Infant follow‐on formulas (IFF) aim to ensure an adequate nutritional intake to support the proper development and infant growth. Therefore, IFF must be stable against degradation phenomena such as lipid oxidation and have a composition and structure that are as biomimetic as possible to mature breast milk. This study provides key information for the development of IFF with a lipid composition and structure that are suitable for the infant nutritional needs and have an acceptable resistance to lipid oxidation. More generally, these results can be applied to all dispersed systems in the form of oil‐in‐water emulsions with a similar composition. [ABSTRACT FROM AUTHOR]

Lipid oxidation in food products is a crucial problem that causes undesirable changes in the food's flavor, texture, and nutritional value. It should be carefully monitored as it can lead to the formation of potentially toxic compounds and in that way reduce the shelf life of the product. Liquid chromatography coupled to mass spectrometry is a powerful tool to monitor the formation of oxidized lipids. However, the presence of lipid species in both their non-oxidized and oxidized forms at distinctly different concentrations can hinder the detection and identification of the less abundant oxidized species, due to coelution. In this study, a flow injection mass spectrometry approach was used to selectively ionize oxidized triacylglycerols versus their non-oxidized precursors. Three mobile phase additives were investigated (ammonium formate, sodium acetate, and sodium iodide) at three different concentrations, and ion source settings (i.e., sheath gas temperature, capillary voltage, and nozzle voltage) were optimized. A fractional factorial design was conducted to examine not only the direct effect of the operating parameters on the selectivity of ionization for the oxidized lipid species, but also to assess their combined effect. Overall, selective ionization of oxidized versus non-oxidized lipid species was favored by the use of sodium-containing solvent additives. The application of specific ion source settings resulted in an increased ionization selectivity, with sheath gas temperature and capillary voltage having the most significant influence. A selectivity factor as high as 120 could be reached by combining 0.1 mg/mL sodium-containing additives, with 250 °C sheath gas temperature and 5000 V capillary voltage. These findings will contribute to future studies on fast detection and relative quantification of low abundant oxidized triacylglycerols and their possible impact on human health. [ABSTRACT FROM AUTHOR]

Lipid oxidation is a major cause of quality deterioration in salad dressings. This study evaluated the effect of incorporating microencapsulated polyphenol extracts via spray drying from pomegranate peels (MPP) to delay lipid oxidation in Italian‐style salad dressings (ISD) during accelerated (55°C) and ambient (25°C) storage conditions. ISDs, prepared at high (5000 rpm) and low (250 rpm) shear rates conditions, were formulated with unencapsulated polyphenol extracts from pomegranate peels (PPP), MPP, and/or grape seed extract (GSE). Lipid oxidation in ISDs was evaluated by measuring peroxide value (PV), iodine value (IV), and TBARS, stored in accelerated and ambient conditions for 21 days and 8 weeks, respectively. Tannis in extracts were measured via HPLC‐DAD and the total hydrolyzable tannin content of PPP and MPP was 283.09 and 427.74 (mg/g extract), respectively. Condensed tannins were not detected in PPP and MPP but were found in GSE (348.53 mg/g extract). Salad dressings prepared at high shear rates had significantly (p <.05) higher emulsion stability than those homogenized at low shear rates. Mixing conditions did not affect the lipid oxidative stability of IDSs. Salad dressing stored under accelerated storage had higher lipid oxidation (higher PV, lower IV, and higher TBARS) after 21 days than IDSs stored under ambient conditions for 8 weeks. ISDs prepared with MPPP showed significantly (p <.05) lower lipid oxidation than the other ISDs at the end of the shelf life studies. Results from the accelerated storage suggested that incorporating MPP could have extended the shelf life of IDSs by 20% compared to using unencapsulated polyphenol extracts. The study demonstrated that MPP delays lipid oxidation in ISDs during storage more effectively than unencapsulated extracts. MPP may serve as a natural and effective functional food ingredient for controlling lipid oxidation in high‐lipid and acidified foods. [ABSTRACT FROM AUTHOR]

[Display omitted] The shelf life of multiphase systems, e.g. oil-in-water (O/W) emulsions, is severely limited by physical and/or chemical instabilities, which degrade their texture, macroscopic appearance, sensory and (for edible systems) nutritional quality. One prominent chemical instability is lipid oxidation, which is notoriously complex. The complexity arises from the involvement of many physical structures present at several scales (1–10,000 nm), of which the smallest ones are often overlooked during characterization. We used cryogenic transmission electron microscopy (cryo-TEM) to characterize the coexisting colloidal structures at the nanoscale (10–200 nm) in rapeseed oil-based model emulsions stabilized by different concentrations of a nonionic surfactant. We assessed whether the oxidative and physical instabilities of the smallest colloidal structures in such emulsions may be different from those of larger colloidal structures. By deploying cryo-TEM, we analyzed the size of very small oil droplets and of surfactant micelles, which are typically overlooked by dynamic light scattering when larger structures are concomitantly present. Their size and oil content were shown to be stable over incubation, but lipid oxidation products were overrepresented in these very small droplets. These insights highlight the importance of the fraction of "tiny droplets" for the oxidative stability of O/W emulsions. [ABSTRACT FROM AUTHOR]

In this study, a linoleic and linolenic acid were incubated with petroleum ether extract, ethyl acetate extract, acetone extract (AE) and aqueous extract of Astragalus membranaceus. The phenolic content and total antioxidant capacity (T-AOC) were determined in the extracts of Astragalus membranaceus (EAms) above. Results showed that EAms decreased the levels of malonaldehyde, conjugated diene, and peroxide value levels in material above. Of all of EAms, AE showed the strongest T-AOC and inhibitory effect on the lipid oxidation. Next, fish feeds were incubated with graded levels of AE. The results showed that AE inhibited lipid oxidation in fish feed. The appropriate dosage for reducing lipid oxidation was 6.74 g AE kg−1 feeds. The effect of EAms on the lipid oxidation may be closely associated with their phenolic content. Then, juvenile Jian carp (Cyprinus carpio var. Jian, 10.2 ± 0.3 g) were fed with diets containing graded levels of AE (0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, and 7.0 g kg−1) for 60 days. Current data displayed that dietary AE increased the growth performance of fish. The optimum dosage for growth promotion was 5.15 g AE kg−1 diet. This result of AE may be ascribed to its enhancing effect on the activity of digestive and absorptive enzymes and antioxidant capacity in digestive organs of fish. Our present study indicated that EAm holds promise as a natural antioxidant for fish and their feed. [ABSTRACT FROM AUTHOR]

Summary: Aqueous extract rich in phenolic compounds and carbohydrates obtained as a co‐product during the trub‐debittering process can be used as a new sustainable ingredient to improve food quality properties. This water‐soluble extract (WE) was used for evaluating its own antioxidant capacity when added to processed cheese at up to 1.00% (w/w); and were also evaluated for total phenolic compounds, antioxidant activity, FTIR spectroscopy, lipid oxidation, oxidative stability, texture and rheological properties. WE addition increased the antioxidant activity of processed cheese by up to 88.40% and 81.90% for DPPH and ABTS, reduced the product lipid oxidation by up to 54.31% and showed greater oxidative stability (Rancimat) compared to the Control. Samples melting property was not changed, and samples with WE showed a more stable structure after melting. Use of WE showed that it can be used as natural antioxidant in processed cheese, improving its quality and texture properties. [ABSTRACT FROM AUTHOR]

Firstly, a linoleic and linolenic acid emulsion were incubated with petroleum ether extract, ethyl acetate extract (EAE), ethanol extract and aqueous extract of Ginkgo biloba leaves. The flavonoids content, total antioxidant capacity (T-AOC) and metal-chelating ability (MCA) were determined in EGbs above. Results showed that the extracts of Ginkgo biloba leaves (EGbs) inhibited the lipid oxidation in material above. Of all of EGbs, EAE showed the strongest T-AOC, MCA and protective effects against the lipid oxidation. Next, fish feeds were incubated with graded levels of EAE. The results showed that EAE inhibited lipid oxidation in fish feeds. The optimal inclusion levels of EAE for minimizing lipid oxidation were 4.26 g kg−1 feeds. The effect of EGbs on the lipid oxidation may be closely associated with their flavonoid content. Finally, juvenile carp (14.8 ± 0.4 g) were fed with EAE at concentrations ranging from 0.0 to 6.0 g kg−1 for 60 days. Current data displayed that dietary EAE increased the growth performance of fish. This result of EAE may be ascribed to its enhancing effect on the activity of digestive and absorptive enzymes and antioxidant capacity in digestive organs of fish. Furthermore, dietary EAE decreased the hot-drying-induced lipid oxidation in fish meat through inhibiting the induction effect of hemoglobin in erythrocytes. Our study suggests that EGb can be considered as a potential natural antioxidant for fish and fish feed. [ABSTRACT FROM AUTHOR]

Summary: This work investigated the antioxidant activity and inhibitory effect of barley green powder (BGP) on the surimi lipid oxidation during frozen storage under different additive amounts. BGP was abundant in antioxidant compounds‐phenolic (1.18 ± 0.04 mg g−1), flavonoid (4.07 ± 0.47 mg g−1) and superoxide dismutase (94.73 ± 21.06 U g−1), with a good ability to scavenge ABTS and DPPH radicals and delay lecithin liposome oxidation. Additionally, adding BGP to surimi decreased acid value, peroxide value, conjugated diene value and thiobarbituric acid reactive substances value (~30%) of surimi during frozen storage (P < 0.05), inhibiting surimi lipid oxidation at early phase and terminal phase. The inhibitory effect showed a concentration dependence, with an optimal addition amount of 3%. Pearson correlation analysis indicated that antioxidant activity and inhibitory effect of BGP on lipid oxidation were significantly correlated with antioxidant compounds content in BGP, suggesting that these activities may be derived from antioxidant compounds in BGP. Our results indicated the potential use of BGP as a natural antioxidant for frozen storage of surimi to delay lipid oxidation. [ABSTRACT FROM AUTHOR]

BACKGROUND: The gastrointestinal (GI) tract is a major site of lipid oxidation, and the lipid oxidation products are related to an increased risk of various chronic diseases. In this study, the inhibition capacity of bound‐polyphenol rich insoluble dietary fiber (BP‐IDF) from highland barley (HB) to lipid oxidation was evaluated during simulated GI digestion. RESULTS: We found that the level of lipid hydroperoxides (LOOH) and aldehydes were significantly inhibited when highland barley bound‐polyphenol rich insoluble dietary fiber (HBBP‐IDF) co‐digestion with cooked pork. The lipid oxidation products were more effectively scavenged during simulated gastric digestion, with inhibition of 77.4% for LOOH, 52.3% for malondialdehyde, 46.5% for 4‐hydroxy‐2‐hexenal and 48.7% for 4‐hydroxy‐2‐nonenel, respectively. The fiber‐bound polyphenols are the principal scavengers of lipid oxidation products. CONCLUSION: These findings suggest that HBBP‐IDF could be used as a functional ingredient able to scavenge lipid oxidation products across the GI tract. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Lipid oxidation is a major cause of quality deterioration in food products. In these foods, lipids are often present in a bulk or in emulsified forms. In both systems, the rate, extent and pathway of oxidation are highly dependent on the presence of colloidal structures and interfaces because these are the locations where oxidation normally occurs. In bulk oils, reverse micelles (association colloids) are present and are believed to play a crucial role on lipid oxidation. Conversely, in emulsions, surfactant micelles are present that also play a major role in lipid oxidation pathways. After a brief description of lipid oxidation and antioxidants mechanisms, this review discusses the current understanding of the influence of micellar structures on lipid oxidation. In particular, is discussed the major impact of the presence of micelles in emulsions, or reverse micelles (association colloids) in bulk oil on the oxidative stability of both systems. Indeed, both micelles in emulsions and associate colloids in bulk oils are discussed in this review as nanoscale structures that can serve as reservoirs of antioxidants and pro-oxidants and are involved in their transport within the concerned system. Their role as nanoreactors where lipid oxidation reactions occur is also commented. [ABSTRACT FROM AUTHOR]

In this study, the antioxidant effects of gallic acid (GA) and its alkyl esters including methyl gallate (MG), butyl gallate (BG), octyl gallate (OG), and lauryl gallate (LG) in whole oyster meats and oyster meat homogenates during cold storage are investigated. The oxidation degree of lipid is measured by peroxide value (POV), thiobarbituric acid active substances (TBARS), and polyunsaturated fatty acid (PUFA) percentage. The results show that the lipid oxidation in the two types of samples is inhibited by GA alkyl esters, and the antioxidant effects first increase and then decrease along with the extension of the chain length, among the esters, BG and OG are relatively more effective. Therefore, it is speculated that the antioxidant capacity of GA alkyl esters may be influenced by hydrophobicity and follows a "cut‐off effect" in whole oyster meats and oyster meat homogenates. Practical application: Seafood is easily oxidized even under cold storage because it contains more PUFA. Antioxidants are widely used to inhibit lipid oxidation. In this study, the antioxidant capacity of GA alkyl esters in whole oyster meats and oyster meat homogenates is investigated, which improves the selection of suitable antioxidants to strengthen the oxidation stability of oyster samples for cold storage. [ABSTRACT FROM AUTHOR]

The effectiveness of commercial oxygen scavengers was investigated in order to increase the shelf-life of sliced dry-cured Iberian shoulder in MAP (modified atmosphere packaging) for up to 150 days. Five dry-cured shoulders from Iberian pigs were used. Slices of these dry-cured shoulders were randomly packaged in MAP conditions. An active packaging (AP) with oxygen scavengers was evaluated to reduce the level of oxygen within the headspace as close to 0% as possible. AP was compared to a Control Treatment (C) (without scavenger). Sliced dry-cured Iberian shoulder in AP showed lower thiobarbituric acid reactive substances values (TBARS) than control packages after 150 days of storage, and in general, volatile compounds derived from lipid oxidation, increased in C packages, whereas these remained steady in AP. Therefore, AP was effective to decrease the development of lipid oxidation during storage. In contrast, AP was not effective in preserving color changes, although no sensory differences between treatments were appreciated by the panelists. [ABSTRACT FROM AUTHOR]

The stability characteristics of soluble nano-sized quinoa protein isolates prepared by different high-pressure homogenization in terms of droplet size and lipid oxidation were studied. Commercial quinoa protein isolates (QPI) were exposed to high-pressure homogenization (HPH) at various pressure (50, 100 and 200 MPa) and pressure cycles (one-cycle and two cycles). The quinoa isolate aggregates were utilized to produce oil-in-water nanoemulsions, which demonstrated the good stabile characteristics for 28 day of storage at 4 ℃. While quinoa protein/canola oil nanoemulsions (QPCON) produced with untreated QPI and QPI samples by other HPH treatments were shown a significant increase in terms of droplet size and lipid oxidation in 28 days of storage, QPI samples treated with HPH at 100 MPa for a cycle (100 MPa-1) was found as the most efficient treatment in the stability of protein aggregate sizes and less oxidation level. The sample showed a slight increase from 98 nm to 117 nm for droplet size and from 58 to 102 mmol/kg for lipid oxidation from day 0 to day 28. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigated a comparative analysis on changes in protein and lipid fractions and quality attributes of camel meat, cattle meat (beef) and sheep meat (mutton). The samples were studied over 9 days of refrigerated storage. Camel meat underwent higher lipid oxidation compared with beef and sheep meat. All meat types showed a decrease in the haem pigments and redness (a* values) indicating the oxidation of the haem pigment. Drip loss was high in camel meat and mutton compared with the beef samples. Camel meat was tougher, with higher hardness values, followed by beef and mutton samples, which decreased over 3 and 9 days of storage, indicating the degradation of structural proteins. In conclusion, the study provided valuable information on the properties of different red meats during storage and variations in their protein and lipid fractions and other quality attributes during storage. An in-depth characterisation of protein and lipid fractions and changes in the physicochemical and meat-quality attributes of camel meat, beef and mutton over 9 days of refrigerated storage was investigated. The lipids of all the meat samples, especially those in camel meat, underwent significant oxidation in the first 3 days of storage. A decrease in pigment and redness (a* value) with an increase in the storage time was noticed in all the meat samples, suggesting the oxidation of the haem protein. The mutton samples displayed greater protein extractability, while the protein solubility values in all the meat samples were similar, and these varied as storage progressed. The drip loss percentage in camel meat and mutton were two times higher than in beef, and it increased during storage period. The textural properties of fresh camel meat were higher than mutton and beef, and these decreased during day 3 and 9, respectively, indicating the proteolysis and the degradation of the structural proteins, which were also evident from the SDS-PAGE pattern. [ABSTRACT FROM AUTHOR]

Kefalotyri cheese made in December and April using milk from sheep grazing on pastures was aerobically kept, in the dark or under fluorescent light, for 40 days at 4°C. Unsaturated fatty acids, which were higher in April than in December cheese, were significantly (P < 0.05) decreased in all cheese samples under both storage conditions. According to lipid hydroperoxides, malondialdehyde and carbonyls changes, grated cheese samples stored under fluorescent light showed a higher protein and lipid oxidation as compared to samples stored in the dark. Sensory and colour characteristics were better for cheeses stored in the dark than those under fluorescent light. [ABSTRACT FROM AUTHOR]

In this study, five different types of fish burgers were produced using 80% ground fish meat, 10% lipid, 6% spices mixture and 4% water. Burgers (5 mm thickness and 90 g weight) were produced using 100% fish oil (control), 75% fish oil and 25% mango kernel oil (MKO) (T1), 50% fish oil and 50% MKO (T2), 25% fish oil and 75% MKO (T3), 0% fish oil and 100% MKO (T4). Burgers were packaged in polyethylene bags and stored at −16 to −18°C for 90 days. The mangiferin, quercetin, catechin, chlorogenic and caffeic acid in MKO were 1381, 87, 512, and 973 mg/100 g. Total antioxidant capacity of control, T1, T2, T3, and T4 were 18.97, 31.47, 47.69, 65.37, and 78.82%. GC-MS analysis showed that ALA, EPA, and DHA) in T2 were 0.85, 3.62, and 4.19%. In controlled storage, loss of ALA, EPA, and DHA was 55, 14, and 11%. At T2 concentration, antioxidant compounds of MKO significantly altered the lipid oxidation in burgers. After storage in T2, loss of ALA, EPA, and DHA was 3.6, 1.98, and 1.71%. POV of 90 days stored control, T1, T2, T3, and T4 was 3.42, 1.55, 0.63, 0.41, and 0.31 (MeqO2/kg). Induction period of fish oil, MKO, in all levels was 2.45, 64.28, 7.33, 13.42, 18.39, and 62.84 hrs. Color flavor and texture score of 90 days stored T2 was 91, 90, and 86% of total score. MKO and fish oil can be used at 50:50 concentrations to formulate fish burgers of acceptable sensory properties. [ABSTRACT FROM AUTHOR]

In this study, dry‐cured Spanish mackerel (Scomberomorus niphonius, DCSM) was prepared via three different methods (hot‐air drying, cold‐air drying, and sun drying). The content of 4‐hydroxy‐2‐hexenal (HHE) and 4‐hydroxy‐2‐nonenal (HNE) derived from lipid oxidation in whole processes was investigated by HPLC‐MS/MS. The changes in fatty acid composition were detected by GC‐MS, and the degree of lipid oxidation was evaluated by the levels of acid values (AV), peroxide values (POV), and thiobarbituric acid‐reactive substances (TBARS). The results showed that the drying process significantly accelerated lipid oxidation in DCSM. The contents of HHE and HNE were significantly increased after processing. The content of HHE was higher by 18.44‐, 13.45‐, and 16.32‐folds compared with that of HNE after three different processes, respectively. The HHE and HNE contents fluctuated upward during the hot‐air and cold‐air drying process. However, the contents of HHE and HNE increased time‐dependent during the sun drying process, with the highest values of 86.33 ± 10.54 and 5.29 ± 0.54 mg/kg fish among the three different processes. Besides, there was a significant positive correlation between HHE contents and n‐3 fatty acids content in hot‐air drying and sun drying processes (Pearson's r =.991/.996), and HNE occurrence was closely related to n‐6 fatty acid content in sun drying process (Pearson's r =.989). Regression analysis indicated that the content of HHE and TOTOXTBA values in DCSM showed good linear relationships (R2 value =.907), which suggested that the content of HHE could be used to estimate the oxidative deterioration of dry‐cured fish products. [ABSTRACT FROM AUTHOR]

The effects of blue light on human body have attracted attention. The human skin in contact with the outside environment is often exposed to blue light, and the effects of this exposure remain to be fully determined. Therefore, in this study, we investigated the effect of blue light, at the intensity typically found in sunlight, on lipids in the skin from an oxidation perspective. Peroxide value (POV) and ultraweak photon emission (UPE) measurements were conducted to evaluate lipid oxidation. Our results confirmed that blue light irradiation induced lipid oxidation, similar to ultraviolet A (UVA) irradiation. Also, the effects of various reagents on the blue light-induced UPE were evaluated; however, the results differed from those of the DPPH radical-scavenging ability. We speculated that this is due to the difference in the evaluation principle; nevertheless, among reagents, hypotaurine not only showed a high antioxidant effect but was also more effective against blue light-induced oxidation than UVA. Based on the difference in the antioxidant effect of the lipid sample in this study, the oxidation reaction induced by blue light may be different from the UVA-induced reaction. Our study provides new insights into the effects of blue light on lipids in the human skin, thereby promoting research regarding photooxidation. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the ability of two freeze-dried extracts from blackberry processing by-products resulted after juice extraction, compared to butylhydroxytoluene (BHT) in preventing the lipid oxidation of sunflower oil (SFO) subjected to high-temperature heating at 180ºC up to 12 hours. The blackberries were collected from spontaneous flora of two regions of Romania, Zugau (Arad County) and Paltinis (Sibiu County) and the blackberry byproducts extracts (BBE) were noted according to the place of origin as ZBBP, respectively PBBE. The evolution of lipid oxidation was tracked by means of specific indices as: peroxide value (PV), p-anisidine value (p-AV), total oxidation (TOTOX) value and the response of TBA-malondialdehyde (MDA) interactions evaluated by thiobarbituric acid (TBA) method. The results revealed that BBE displayed a high inhibitory effect on SFO thermo-oxidation. This response was dose-dependent, thus, the rate of lipid oxidation was inversely related to BBE concentration. The recorded data highlighted that BBE constitutes efficient natural antioxidants that can contribute to the development of sunflower oil with extended thermo-oxidative stability. [ABSTRACT FROM AUTHOR]

This study investigated the effect of NaNO2 on inhibiting myoglobin-mediated lipid oxidation in muscle using a washed bovine mince model. We measured various parameters, including TBARS and PV to determine lipid oxidation, non-heme iron release, protoporphyrin destruction, and nitrosylmyoglobin production. The results of the study showed that the addition of NaNO2 during myoglobin-mediated lipid oxidation significantly reduced the fading and lipid oxidation of washed muscle (p < 0.05). Additionally, the addition of NaNO2 reduced the release of non-heme iron and the degradation of protoporphyrin in myoglobin. Nitrosylmyoglobin was formed in the washed mince supplemented with NaNO2 and myoglobin. These findings suggest that NaNO2 can effectively inhibit the lipid oxidation process induced by myoglobin, which could be a crucial aspect of nitrite inhibition of lipid oxidation in cured meat products. Overall, the study provides evidence for the potential use of NaNO2 as a food preservative to prevent lipid oxidation in meat products. [ABSTRACT FROM AUTHOR]

The deeply oxidized pork fat (PF) is the key in the production of Chi‐aroma Baijiu, a Chinese distilled spirit. Previous studies have not proposed an integrated method to promote lipid oxidation of PF, and the formation of volatiles has not been studied. In this work, an efficient method was established to promote lipid oxidation and release of volatiles of pork fat pulp (PFP) in an integrated treatment for the production of Chi‐aroma Baijiu. The results showed that the acid value of PFP by lipase pretreatment (T1) was significantly elevated (p < 0.05), compared to the control (T0). Lipase‐blue light‐riboflavin‐25°C (T2), lipase‐open vial‐dark‐25°C (T3), and lipase‐dark‐40°C (T4) further promoted lipid oxidation and reached the oxidation level of PFP by F0, while T2 show the best results. The peroxide value of PFP by T2, T3, and T4 was 41.96‐, 16.70‐ and 14.20‐fold higher, and the para‐anisidine value was 27.13‐, 6.94‐ and 6.70 fold higher than that in T1. The flavor and volatile analyses showed that PFP by T2 had higher response values than T0 at six electronic nose sensors. T2–T4 promoted the release of volatiles and T2 showed the best result. T2 potentially facilitated lipid oxidation, esterification, and substance exchange of PFP, resulting in a higher type (78.57%) and content (114.50%) of volatiles than T0. The integrated treatment with lipase hydrolysis, blue light with riboflavin could promote lipid oxidation and volatiles release to improve production efficiency of deeply oxidized PF. The results would be viably applied to the production of Chi‐aroma Baijiu. Practical Application: Deeply oxidized pork fat was the key to the production of Chi‐aroma Baijiu, while it took a long time (at least 4 months) to prepare. The integrated treatment with lipase hydrolysis, blue light with riboflavin could promote lipid oxidation and volatiles release to improve the production efficiency of deeply oxidized pork fat. The results would be viably applied to the production of Chi‐aroma Baijiu. [ABSTRACT FROM AUTHOR]

Concerns have been raised about the safety and tolerability of phytosterol esters due to their vulnerability to oxidation. Herein, oxidation of the unsaturated fatty acid-phytosterol ester, namely β-sitosteryl oleate, was observed in comparison to native β-sitosterol after accelerated storage at 65 °C for 35 days in a bulk oil model system. Depending on the sterol structure, various chemical indices of lipid oxidation, including hydroperoxide value (HPV), thiobarbituric acid reactive substances (TBARS), p-anisidine value (AnV), and 7-keto derivatives, changed at varying rates in both samples. Such indicators for β-sitosteryl oleate appeared to be obtained at higher concentrations than those for β-sitosterol. The first order kinetic was used to describe the losses of β-sitosteryl oleate and β-sitosterol in bulk oil. It was discovered that the β-sitosteryl oleate (k = 0.0202 day−1) underwent oxidative alteration more rapidly than β-sitosterol (k = 0.0099 day−1). Results indicated that physical structure was the principal factor in the determination of storage stability of phytosterol and its ester. Research on antioxidants and storage techniques can be expanded in order to reduce the oxidative loss of phytosterol esters during storage and improve the safety and tolerability of phytosterol esters. [ABSTRACT FROM AUTHOR]

Wheat germ is an agricultural but low-economic by-product for animal feed or waste due to its susceptibility of hydrolytic/oxidative rancidities. Here, we use controllable extrusion to treat wheat germ, and with assistance of exogenous starch as lipid protective factor at different ratios (0:10 2:8, 3:7, 4:6). Oxidation of optimized germ extrudate was slowed down during storage, with total lipid retention rate reach up to ∼88.3%. Extrusion dynamic analysis showed that relatively high screw speed (100–150 rpm) significantly shortened mean residence time, increased axial diffusion velocity and reduced the loss of free and bound lipid. Type Ⅱ starch-lipid complex was changed to type Ⅰ during extrusion, with thermal transition peak declined. Wheat germ lipid was most evenly distributed under 100 rpm extrusion. The hydrogen bonding interaction between exogenous starch and lipids in wheat germ was strengthened, with significant modification in water absorption, water solubility, expansion and textual indexes. • The controllable lipid retention of wheat germ was achieved by extrusion. • Lipid oxidation index of extruded wheat germ was greatly reduced during storage. • Lipid content was changed and clarified by chemical and RTD analyses. • Wheat germ-based complex was prepared with exogenous starch at 0–40%. • Lipid loss rate was decreased to 11.71% in wheat germ-starch extrudate. [ABSTRACT FROM AUTHOR]

The study investigated the lipid oxidation of pumpkin seed kernels (PSK) under different storage conditions (room temperature, vacuum-room temperature, refrigeration, and vacuum-refrigeration) using HPLC-MS and GC–MS. Experimental results found the vacuum-refrigeration group showed the lowest PV (0.24 g/100 g), diene (8.68), hexanal (356.64 ± 16.06 ng/g), and nonanal (132.05 ± 8.38 ng/g) after a 9-month storage. A total of 586 lipids, including 6 classes and 27 subclasses, were detected, 46 of which showed significant differences. Refrigeration samples had the highest diacylglycerol content, while room temperature samples demonstrated the highest triacylglycerol and phosphatidylcholine content. Differential lipid metabolite analyses indicated that storage conditions mainly affected glycerolipid metabolism, glycerophospholipid metabolism, and sphingolipid metabolism pathways in PSK, while glycerolipid and glycerophospholipid metabolism were still dominant. It revealed that refrigeration was more effective than vacuum in inhibiting the oxidation of PSK. These findings could offer valuable references for the storage, transportation, preservation, and the development and utilization of PSK. [Display omitted] • Aldehydes and alcohols were main differential flavor compounds in PSK. • Storage conditions significantly impacted the lipid oxidation degree of PSK. • 589 lipid metabolites, including 6 classes and 27 subclasses, were identified. • Lipid metabolism pathways in PSK under different storage conditions were revealed. [ABSTRACT FROM AUTHOR]

• Extended food use of oats calls for knowledge on compositions and storage behavior. • Lipids, volatiles and tocopherols varied between 20 pure oat cultivar batches. • Nine-month storage of flour revealed differences in oxidative stability. • Minor correlations between lipids, tocols and volatile oxidation compounds detected. Recent data showing the compositional variation and storage behavior among different oat batches for the purpose of food remains limited. Lipids of twenty oat flour samples of pure cultivars grown in Finland during 2019 were extracted and fractionated into neutral and polar-rich lipids. Flour was stored for nine months, and profiles of volatiles and tocols were analyzed to reveal oxidative stability. The lipid content was 5.9–8.9 g per 100 g of flour [DW] and consisted of 78.7 ± 2.5 % neutral and 21.3 ± 2.5 % polar lipids. Palmitic (16 %), oleic (36 %), and linoleic (39 %) acids were the most abundant fatty acids. Neutral lipids had more oleic and less linoleic and palmitic acids than polar lipids. The fresh samples correlated with tocols, pentanal, 2-pentylfuran, 2-heptanone, nonanal, 2-butanone, and heptanal, while stored samples were associated with 3-octen-2-one, 2-octenal, hexanal, and octanal. Lipid composition and oxidative stability are essential factors for selecting oat batches for food applications. [ABSTRACT FROM AUTHOR]

Models predicting lipid oxidation in oil-in-water (O/W) emulsions are a requirement for developing effective antioxidant solutions. Existing models do, however, not include explicit equations that account for composition and structural features of O/W emulsions. To bridge this gap, a mechanistic kinetic model for lipid oxidation in emulsions is presented, describing the emulsion as a one-dimensional three phase (headspace, water, and oil) system. Variation in oil droplet sizes, overall surface area of oil/water interface, oxidation of emulsifiers, and the presence of catalytic transition metals were accounted for. For adequate predictions, the overall surface area of oil/water interface needs to be determined from the droplet size distribution obtained by dynamic and static light scattering (DLS, SLS). The kinetic model predicted well the formation of oxidation products in both mono- and polydisperse emulsions, with and without presence of catalytic transition metals. • Mechanistic kinetic model describes lipid oxidation in oil-in-water (O/W) emulsions. • Compositional and structural features of O/W emulsions are included in the model. • Droplets with sizes <300 nm need to be accounted for in the model. • Kinetic rates of lipid oxidation vary with the droplet size. • Model provides good predictions for mono-and polydisperse emulsions. [ABSTRACT FROM AUTHOR]

This study aimed to determine the ability of black rice bran oil (RBO) to extend the shelf life and quality of fresh ground beef patties. The beef samples were treated with four different concentrations of RBO (0%, 0.2%, 0.4%, and 0.8% [v/w]). The ground beef patties were packaged in polyvinyl chloride (PVC) and cold storage at 2 - 4°C. pH, color appearance, lipid oxidation, antioxidant activity, and aerobic plate count were determined on 0, 3, and 6 days of storage. The result found that adding RBO did not affect pH (P>0.05). The microbial population and lipid oxidation value in all groups increased in all samples following the storage time of up to 6 days. However, the beef sample addition with 0.4% RBO decreased lipid oxidation compared with the control group and reduced the microbial population counts after six days (P<0.01). According to the results, RBO could be used as a natural bio-preservative in ground beef to prolong its shelf life. [ABSTRACT FROM AUTHOR]

Supplementation of omega-3 fatty acids is considered a valuable strategy to supply the low intake of these fatty acids. Thus, the safety of the supplements is an important milestone. Because of that, we analyzed 20 unflavored supplements sold in the French market for fatty acid and triglyceride composition, for EPA and DHA, and for tocol content, as well as for oxidative status. This study found that only 2.5% of the supplements did not meet their label claims for omega-3 content. TAG analysis showed high variability among the triglyceride distribution, and the same trend was also noticed for the tocol content; in fact, a high variability of the distribution of the six tocols (four tocopherols and two tocotrienols) was found among the samples. Of the tested products, all of them complied with peroxide value, p-anisidine value, and Totox values established by the Global Organization for EPA and DHA Omega-3s (GOED) and were not oxidized. [ABSTRACT FROM AUTHOR]

Equivocal findings regarding the influence of overweight/obesity on exercise lipid-oxidizing capacity (EX-LIPOX) might reflect inadequate control of 1) acute energy balance/macronutrient composition of diet; 2) intensity/duration of exercise; and/or 3) insulin sensitivity (IS) of participant. To assess independent/combined influences of IS and overweight/obesity with other factors controlled, we recruited sedentary adults with normal weight (NW; n = 15) or overweight/obesity (O; n = 15) subdivided into metabolically healthy (MH; n = 8) and unhealthy (MU; n = 7) groups (IS; MH > MU). Participants completed a 9-day, weight-stabilizing, controlled-feeding protocol comprising measurements of resting metabolism, body composition, oral glucose tolerance, and maximal exercise capacity. We measured EX-LIPOX during the initial 45 min of “steady state” during constant-work-rate cycling at 70% and 100% of participant gas-exchange threshold (GET). At 70%, average EX-LIPOX in absolute (0.11 ± 0.02 g·min-1 ) and relative (2.4 ± 0.3 mg·kgFFM-1 ·min-1 ) terms was lower for NW-MU than MH regardless of body composition (NW-MH, 0.19 ± 0.02 g·min-1 /3.9 ± 0.3 mg·kgFFM-1 ·min-1 ; O-MH, 0.19 ± 0.02 g·min-1 / 3.7 ± 0.3 mg·kgFFM-1 ·min-1 ), whereas no difference was present for NW-MU and O-MU (0.15 ± 0.02 g·min-1 /2.8 ± 0.3 mg·kgFFM-1 ·min-1 ). Multiple regression confirmed that with IS-controlled, overweight/obesity was not associated with decreased EX-LIPOX, whereas decreased EX-LIPOX was associated with decreased IS independent of overweight/obesity. Overweight/obesity also did not influence EX-LIPOX across MH groups or with cohort divided by body-composition classification alone (P > 0.05). Exercise lipid-oxidizing capacity is impaired with poor IS regardless of body composition, but not with overweight/obesity per se. NEW & NOTEWORTHY In this study, we have shown that the capacity to oxidize lipid during exercise is influenced by metabolic health of the exerciser regardless of body composition, but not by body composition per se. This observation refutes the belief that a reduced capacity to oxidize lipid is an obligatory characteristic of the overweight/obese condition while supporting the contention that exercise should be prescribed with specificity based on both absence/presence of overweight/obesity and compromise/lack thereof in metabolic health. [ABSTRACT FROM AUTHOR]

The current work was conducted to explore the influence of two non-thermal technologies (high pressure homogenization (HPH) and high-intensity ultrasound (HIU)) on emulsifying properties, droplet size, turbidity and lipid oxidation of pea protein-stabilized nanoemulsions (PPNs) during seven days of storage. The smallest droplet size (198.3 nm) was obtained for the samples exposed to 10 min HIU at 100% amplitude among all treatments. The same sample also showed the least lipid oxidation (98 mmol/kg) during storage. There was a positive relationship between droplet size and turbidity values. All HIU-treated PPNs exhibited less turbidity and smaller droplet size where the control PPN samples demonstrated the most turbid structure (4.05) with the biggest droplet size (413.9 nm). Similar positive relationship was also found between the variables of droplet size and lipid oxidation. All HIU-treated PPNs exhibited less lipid oxidation and smaller droplet size where the control PPNs demonstrated the most lipid oxidation with the biggest droplet size. Last but not least, among the treatments, the PPNs exposed to 10 min HIU at 100% amplitude showed the highest emulsifying activity index (EAI, 212 m²g -1 ) and emulsifying stability index (ESI, 59 min), whereas the PPNs with no treatment showed the lowest EAI (69 m²g -1 ) and ESI (21 min). [ABSTRACT FROM AUTHOR]

Summary: This study investigated the antioxidant properties of pepper (Zanthoxylum bungeanum Maxim.) leaf (ZL) extract as a natural oxidative agent against lipid and protein oxidation during larou processing. The phenolic profile of the ZL extract was assessed by HPLC and the ZL extract exhibited high 2,2 diphenyl‐1‐picryl‐hydrazyl (DPPH) (0.46 ± 0.07 mg mL−1) and 2,‐2′‐azino‐di‐(3‐ethylbenzothiazoline sulfonic acid (ABTS) (0.38 ± 0.04 mg mL−1) radical scavenging activity. The lipid and protein oxidation of larou was evaluated during the whole process with 0.02%, 0.04%, and 0.06% ZL extracts. Results showed that larou incorporation with ZL extracts significantly delayed the formation of thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD) and peroxide values (POV), and carbonyls (P < 0.05). In contrast, the surface hydrophobicity and intrinsic tryptophan fluorescence intensity were decreased (P < 0.05). Meanwhile, we found that the deceleration of sulfhydryl and protein solubility loss was observed in a concentration‐dependent manner (P < 0.05). Moreover, owing to the inhibitory effect of ZL extracts on lipid and protein oxidation, the sensory qualities of larou were improved during processing with increasing concentrations of ZL extract. These results suggested that ZL extract has huge prospects for application in dry‐cured meat processing. [ABSTRACT FROM AUTHOR]

BACKGROUND: The INFOGEST model is a standardized general in vitro digestion study, but it cannot accurately simulate the fatty acid release process of lipids in the stomach and small intestine. In this study, the internationally universal INFOGEST 2019 was used as the basic model and flaxseed oil emulsion was used as the research object. In various improvement models, the effect of fatty acid release rate on the oxidation stability of flaxseed oil was assessed by adding rabbit stomach extract and changing the order of bile salts addition. RESULTS: With the presence of rabbit gastric extract, flaxseed oil emulsion flocculation and coalescence in stomach were reduced, and the absolute value of ζ‐potential increased. Moreover, the release rate of fatty acids in the small intestine increased by 12.14%. The amount of lipid oxidation product (i.e. hexanal) in the gastric and intestinal phases increased by 0.08 ppb. In addition, the fatty acid release rate in the small intestine phase increased by 5.85% and the hexanal content increased by 0.011 ppb in the digestion model of adding bile salts before adjusting the pH in the small intestine phase compared with the model of adjusting the pH first and then adding bile salts. CONCLUSION: The results obtained from this study will contribute to finding the most suitable static digestion model for simulating digestion and oxidation of lipid during lipid gastrointestinal digestion. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Lipids in food are a source of essential fatty acids and also play a crucial role in flavor and off-flavor development. Lipids contribute to food flavor generation due to their degradation to volatile compounds during food processing, heating/cooking, and storage and/or interactions with other constituents developed from the Maillard reaction and Strecker degradation, among others. The degradation of lipids mainly occurs via autoxidation, photooxidation, and enzymatic oxidation, which produce a myriad of volatile compounds. The oxidation of unsaturated fatty acids generates hydroperoxides that then further break down to odor-active volatile secondary lipid oxidation products including aldehydes, alcohols, and ketones. In this contribution, a summary of the most relevant and recent findings on the production of volatile compounds from lipid degradation and Maillard reactions and their interaction has been compiled and discussed. In particular, the effects of processing such as cooking, drying, and fermentation as well as the storage of lipid-based foods on flavor generation are briefly discussed. [ABSTRACT FROM AUTHOR]

BACKGROUND Because many common foods are emulsions (mayonnaise, margarine, salad dressing, etc.), a better understanding of lipid oxidation is crucial for the formulation, production, and storage of the relevant consumer products. We prepared oil‐in‐water (O/W) and water‐in‐oil (W/O) emulgels, and their architecture was characterized before monitoring lipid oxidation under thermally accelerated conditions to systematically compare the effect of emulsion type, oil composition, and oil fraction on the structure and lipid oxidation in thee biphasic emulgel systems. RESULTS: Higher susceptibility of lipids to oxidation (>2.5 times) was observed in the biphasic O/W and W/O emulgels than in soybean oil owing to an interfacial region. In the heterogeneous emulsion systems, W/O emulgels had oxidation resistance than O/W emulgels did. Compared with the oil‐phase composition of high oleic sunflower, soybean, and flaxseed oils, oxidation sensitivity of emulsified lipids was significantly raised as the degree of unsaturation increased from 100.72 to 203.07. Moreover, increasing oil fraction from 75% to 85% led to an obvious increase in total oxidation in O/W emulgels but a decrease in W/O emulgels. In addition to emulsion size and oil unsaturation, viscoelasticity had a remarkable effect on the low‐unsaturated oil oxidation (e.g. high oleic sunflower oil). CONCLUSION: Physical and structural phenomena played important roles in lipid oxidation based on a mass transport principle. These findings provide novel information for designing the structures of emulsion gels for controlling lipid oxidation through the cooperation of both formulation and architecture principles. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The formation of small droplets in emulsion systems promotes lipid oxidation, affecting their shelf life. In this study, ferulic acid was covalently grafted onto coconut protein (CPI) through alkaline treatment method. The structural characteristics, interfacial properties, emulsifying properties, and oxidative stability of emulsions prepared by coconut protein-ferulic acid covalent complexes (CPF) were investigated. The results showed that covalent grafting of ferulic acid could change the physicochemical properties of coconut protein, including altering protein secondary and tertiary structures, enhancing the absolute value of zeta potential and antioxidant activity [2, 2-diphenyl-1-picrylhydrazyl (DPPH•) and 2, 2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+)]. Meanwhile, the interfacial behavior of CPI and CPF was characterized by dissipative quartz crystal microbalance and dilatational rheology analysis. Compared to CPI, CPF could diffuse to the oil-water interface quickly (from 0.084 ± 0.002 to 0.154 ± 0.003 mN/m/s1/2), and formed a thick interfacial layer dominated by elasticity, which enhanced the centrifugal stability of CPF-stabilized emulsions and effectively inhibited lipid oxidation within a 15-day storage period. Our results clearly demonstrated that coconut protein-ferulic acid conjugated complexes could improve emulsion stability and mitigate lipid oxidation, owing to the strong electrostatic repulsion interaction and high diffusion rate at interface. These findings may provide comprehensive insights for the further design and development of protein-polyphenol covalent complexes in the food industry. [Display omitted] • The structure of coconut protein was modified after the conjugation of ferulic acid. • CPF covalent complexes could formed thicker interfacial layer than CPI. • Lipid oxidation was mitigated via ferulic acid conjugated to coconut protein. • The high K diff value of emulsifier to O/W interface enhanced emulsion stability. [ABSTRACT FROM AUTHOR]

• Application of ultrasound technology to freeze storage. • UIF-175 W can effectively minimized the changes in MP structure. • UIF-175 W can protect the lipid during the freeze process. • A schematic illustration of protein and lipid oxidations was proposed. In this study, large yellow croaker (Larimichthys crocea) was frozen using multi-frequency ultrasound-assisted freezing (MUIF) with different powers (160 W, 175 W, and 190 W, respectively) and stored at −18 °C for ten months. The effect of different ultrasound powers on the myofibrillar protein (MP) structures and lipid oxidation of large yellow croaker was investigated. The results showed that MUIF significantly slowed down the oxidation of MP by inhibiting carbonyl formation and maintaining high sulfhydryl contents. These treatments also held a high activity of Ca2+-ATPase in the MP. MUIF maintained a higher ratio of α-helix to β-sheet during frozen storage, thereby protecting the secondary structure of the tissue and stabilizing the tertiary structure. In addition, MUIF inhibited the production of thiobarbituric acid reactive substances value and the loss of unsaturated fatty acid content, indicating that MUIF could better inhibit lipid oxidation of large yellow croaker during long-time frozen storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pea protein isolate is a promising emulsifier to produce oxidatively stable DMOs. • Phytic acid did not provide the high oxidative stability of pea protein isolate. • Verification of the fat fractionation efficacy is of paramount importance. • Raman microscopy is useful for fat fraction visualisation in DMOs. Lipid oxidation limits the shelf-life of dried microencapsulated oils (DMOs), such as infant formula. However, it is poorly understood how lipid oxidation is affected by different types of emulsifiers. To improve our understanding, we prepared DMOs with different emulsifiers (whey protein isolate (WPI), pea protein isolate (PPI), and non-proteinaceous CITREM) and studied lipid oxidation in both the free and encapsulated fat. Only a small difference in oxidation rate was observed between these fat fractions for all formulations. We ascribed this to a non-discrete distribution of the fractions and the subsequent low fractionation selectivity as shown by Raman microscopy. The DMO with PPI showed hardly any oxidation during a 7-week incubation at 40 °C, whereas the DMOs with WPI and CITREM both reached significantly higher contents of oxidation products (lipid hydroperoxides, aldehydes, and epoxides). The enhanced stability of DMO-PPI could not be ascribed to the presence of phytic acid. In conclusion, we demonstrate the potential of using PPI to produce oxidatively stable DMOs. [ABSTRACT FROM AUTHOR]

Lipid oxidation is the principal driver of meat and meat product deterioration during shelf life, causing the loss of fresh meat color, flavor, and aroma. Currently, synthetic antioxidants are used to prevent oxidation, but increasing consumer demand for natural ones leaves the industry with few alternatives. In this study, protocatechuic acid (PCA), known to have high antioxidant activity, was evaluated as a potential inhibitor of meat lipid oxidation. For this purpose, the antioxidant capacity and lipoxygenase (LOX) inhibitory activity of PCA were evaluated in vitro , and a set of four experiments was conducted, treating minced meat with water (control), lactic acid (LA), rosmarinic acid (RA) and PCA, at different concentrations (1–12 mg mL−1), depending on the experiment. The potential antioxidant effect of PCA when applied to meat cubes was also evaluated, as well as the potential of carboxymethyl cellulose (CMC) as a delivery system for PCA. The in vitro results showed that PCA is a potent antioxidant and an effective LOX inhibitor at 1 mg mL−1. PCA effect on meat lipid oxidation prevention was dose-dependent, and at 2 mg mL−1, it inhibited color change by 50% and lipid peroxidation by up to 70% when compared to water-treated samples, performing better than RA at 0.25 mg mL−1. These results suggest that PCA is a promising molecule to the meat industry as a natural preservative for meat and meat products directly or in a formulation. [ABSTRACT FROM AUTHOR]

[Display omitted] • The development of peanut oil volatile flavor requires oil to participate in thermal reaction. • Heating peanut oil to degrade the unsaturated fatty acids in the oil creates reducing aldehydes. • Linoleic acid is one of the precursors in the formation of the volatile flavor of peanut oil. • Develop a volatile flavor model capable of distinguishing different reactions. Lipid is an important precursor for volatile flavor formation, but it is not clear how to study the reactions involved in forming key volatile flavor compounds in peanut oil. In this paper, we innovatively established a flavor research model to investigate the contribution of different chemical reactions to the aroma compounds of peanut oil. The results showed that lipid participation in thermal reactions is necessary for forming major aroma compounds in hot-pressed peanut oil. Compared to the Maillard reaction, the lipid oxidation-Maillard reaction produces more compounds with 46 volatile substances identified. During the heating process, six new key substances were formed and the level of unsaturated fatty acids decreased by 7.28%. Among them, linoleic acid may be an important precursor for the formation of aroma components of hot-pressed peanut oil. Our study could provide theoretical guidance for understanding the volatile flavor mechanism of peanut oil and improving volatile flavor. [ABSTRACT FROM AUTHOR]

Lipid oxidation is the major form of deterioration in salted-dried fish during storage. We here studied the use of Stevia rebaudiana stem (SRS) waste for impeding lipid oxidation of salted-dried Pacific saury fillets during chilled storage. Compared with Vitamin C (VC), the SRS extract (0.2%) significantly delayed lipid oxidation of the salted-dried fish, as determined through assays of the peroxide value, conjugated diene, thiobarbituric acid reactive substances, and acid value; VC is commonly used in salted-dried products. The color results further confirmed the feasibility of the SRS extract in maintaining the quality of the salted-dried Pacific saury fillets. The antioxidant mechanism studies unveiled that the SRS extract exhibited a higher Fe2+-chelating ability than VC, whereas the extract exhibited lower DPPH and ABTS radical-scavenging abilities than VC. This indicated that the high efficacy of the SRS extract in retarding lipid oxidation may be attributable to its higher Fe2+-chelating ability. The in situ Fe2+-chelating assay conducted using confocal laser scanning microscopy further confirmed this conclusion. Potential functional phenolic compounds in the SRS extract were then profiled using the LC-MS method. The SRS waste extract can thus be applied as a natural antioxidant for delaying lipid oxidation of salted-dried fish. • The SRS extract retarded lipid oxidation of salted-dried fish. • The SRS extract (0.2%) was better than VC in retarding lipid oxidation. • The phenomenon may be attributable to the SRS extract having a better Fe2+ chelating ability than VC. • The SRS waste extract can be a source of natural antioxidants in fish products. [ABSTRACT FROM AUTHOR]

Air frying has garnered consumers' attention as an alternative method to deep-fat frying as it does not require oil addition. However, this technology provides a prooxidant environment for oxidative reactions in lipids. Therefore, in addition to industrial approaches, it is worth also considering domestic strategies such as the addition of natural antioxidants during home cooking to limit lipid oxidation. This study presents an overview of the main traits reported for air fryers. Furthermore, as an in-depth review was performed it provides scientifically accurate information on the impact of air frying on food lipids. Given the importance of mitigating lipid oxidation during home cooking, the insights into the use of natural antioxidants are also described. Lipid oxidation during air frying is evidenced by the formation of oxidation products, such as cholesterol oxides, and the degradation of bioactive lipids, like n3 -fatty acids. Moreover, several studies on the formation of secondary oxidation products and volatile compounds can be found. Most studies were carried out with fish and fish products, indicating the need for considering other food matrices. Although using natural antioxidants during cooking is an issue extensively reported, there are few studies regarding this practice during air frying. The current trends underscore the use of herbs and condiments. Besides, following the growing tendency, by-products have also been explored. Promising results were reported, but there are numerous opportunities for further studies aiming to evaluate different natural materials, requiring deeper investigations. [Display omitted] • Air frying provides a prooxidant environment for oxidative reactions in lipids. • Air frying induces lipid oxidation in different food matrices. • Natural sources of antioxidants limit lipid oxidation during air frying. • Herbs, condiments, and natural extracts are suitable domestic strategies. • Studies on different food matrices and new sources of antioxidants are needed. [ABSTRACT FROM AUTHOR]

Ruminant meats contain functional lipids including fatty acid esters of hydroxy fatty acids (FAHFA), diglycerides (DG), monoacetyldiglycerides (MAcDG) and medium chain triglycerides (McTG) whose consumption in the normal diet can confer benefits for consumer health. However, very little is known concerning how meat processing techniques such as marination and grilling affect the quantity and quality of these functional lipids in ruminant meats. We used ultra high-performance liquid chromatography coupled to high resolution accurate mass tandem mass spectrometry (UHPLCHRAM-MS/MS) to show how grilling following marination with either India or Wheat ale unfiltered beer-based marinades affected the quantity and quality of these functional lipids in ruminant meats. We observed MAcDG was completely degraded in grilled meats. Both unfiltered beer-based marinades retained higher (p < 0.05) levels of FAHFA, DG and McTG in grilled meats compared to their unmarinated counterparts. Furthermore, India ale-based marinade was more effective (p < 0.05) compared to Wheat ale-based marinade in preserving these lipids in marinated grilled beef and moose meat. Significantly, strong correlations between antioxidants, polyphenols and oxygenated terpenes present in the marinades and preserved lipid molecular species appear to suggest that antioxidants, polyphenols, and oxygenated terpenes present in the marinades could be associated with preservation of these functional lipids in the grilled meats. These findings appear to suggest that marination could preserve some of these functional lipids with India ale-based marination proving to be more effective. However, further work is required to better improve the retention of MAcDG in grilled ruminant meats. This could potentially increase consumption of FAHFA, DG, MAcDG and McTG in the diet and thereby promote consumer health. [ABSTRACT FROM AUTHOR]