Prevent Lipid Oxidation Research Articles

Adverse effects of linoleic acid: Influence of lipid oxidation on lymphatic transport of citrus flavonoid and enterocyte morphology

Lipids usually contain a large ratio of polyunsaturated fatty acids (PUFAs), which are highly susceptible to oxidation. Presence of oxidized lipids in foods may affect the bioavailability of lipophilic bioactive components after ingestion. In this study, the effect of oxidized and unoxidized linoleic acid (LA) on the transport of a highly lipophilic bioactive citrus flavonoid (5-hydroxy – 6, 7, 8, 4′ tetramethoxylflavone or 5-DMT) was determined using a Caco-2 cell model. Results demonstrated that compared to free 5-DMT, unoxidized LA improved the trans-enterocyte absorption of 5-DMT by stimulating the production of lipid droplets and chylomicrons. Although the amount of 5-DMT transported across the enterocyte doubled by oxidized LA compared to free 5-DMT, it significantly induced reactive oxygen species (ROS), affected the function of tight junction and caused damages to the morphology of enterocyte monolayer. This study re-emphasized the importance of preventing lipid oxidation in foods.

Chemical changes and antioxidant activities of heated whole barley extracts.

Chemical profiles of ethanolic (70%) and aqueous extracts of whole barley heated at 150, 190, and 230°C were analyzed by GC-MS and their antioxidant properties were studied in vitro, in bulk oil, or in an oil-in-water (O/W) emulsion systems. More chemicals were detected in the ethanolic extract than in the aqueous extract from heated barley; heating decreased the contents of detected chemicals. Organic acids, mono- and di-saccharides, sugar alcohols, and glycerol were the major chemicals detected in both the extracts. Ethanolic extracts possessed higher in vitro antioxidant activities than the aqueous extracts. However, this trend was not clearly observed in the bulk oil and O/W emulsion. For O/W emulsions, ethanolic extracts obtained following heating at 150°C prevented lipid oxidation better than others. Therefore, heat treatment at 150°C is recommended to enhance the antioxidant activities of whole barley.

The Antioxidant Effect of Colombian Berry (Vaccinium meridionale Sw.) Extracts to Prevent Lipid Oxidation during Pork Patties Shelf-Life.

A scarce amount of knowledge about the use of Colombian berry (CB) in meat products is available in the literature. This work studies the impact of the addition of CB extracts (CBE) on pork patties at three different concentrations in the range 250–750 mg/kg. CBE were characterized in terms of their polyphenolic profile and antioxidant activity [1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity, half maximal inhibitory antioxidant concentration (IC50), 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), ferric reducing antioxidant power assay (FRAP) and oxygen radical absorbance capacity (ORAC) tests)]. After pork patties elaboration, instrumental and sensorial colour, as well as lipid oxidation measured as thiobarbituric acid reactive substances assay (TBARS) values, were evaluated for 10 days of refrigerated storage in a modified atmosphere (80% O2–20% CO2). The total anthocyanin composition represented 35% of the polyphenolic substances of the CBE, highlighting high contents in cyanidin derivatives. Additionally, other flavonoids (quercetin and kaempferol compounds) and phenolics acids, substances positively related to antioxidant activity, were identified and quantified. In addition, the incorporation of CBE resulted in improvements in colour and lipid stability of pork patties, especially for the highest concentration used. Our findings demonstrated that CBE could be added to pork patties without impairing their sensorial profile. Overall, our results indicate that the use of CBE as a source of natural antioxidant, natural colourant, or even as a functional ingredient could be promising, but more studies are necessary to confirm it.

Carboxymethyl cellulose-based multifunctional film combined with zinc oxide nanoparticles and grape seed extract for the preservation of high-fat meat products

CMC-based functional films incorporated with grape seed extract (GSE, 5 wt% of CMC) and zinc oxide nanoparticles (ZnONPs, 1, 2, and 3 wt% of CMC) were fabricated via the solution casting method. The addition of GSE provided an excellent antioxidant activity to the CMC-based films, exhibiting nearly 95% and 25% scavenging activity against ABTS and DPPH oxidative free radicals. It also gave the film 100% UV protection. On the other hand, the addition of ZnONPs increased the mechanical and water vapor barrier properties with potent antibacterial activity against foodborne pathogens, E. coli, and L. monocytogenes. High-fat beef was packaged in the CMC-based film and stored refrigerated for 15 days to investigate quality changes. The number of psychrotrophic bacteria in the meat wrapped with CMC/ZnO3%/GSE film was 5.9 Log CFU/g, within the acceptable range. In addition, the film virtually prevented lipid oxidation in the meat when refrigerated, reducing it by 88%. Therefore, the CMC/ZnO3%/GSE film can be used as a sustainable material in active packaging applications of high-fat meat products such as beef.

Effects of Rocket Seed Oil, Wheat Germ Oil, and Their Mixture on Growth Performance, Feed Utilization, Digestibility, Redox Status, and Meat Fatty Acid Profile of Growing Rabbits

Vegetable oils are a source of natural antioxidants, including tocopherols, sterols, phenolic compounds, coenzymes, and polyunsaturated fatty acids that provide nutritional value, organoleptic properties, and significantly delay or prevent lipid oxidation. Eighty-four V-line rabbits at 5 weeks of age with an initial body weight (BW) of 535.60 ± 13.48 g were assigned randomly to four experimental groups (seven replicates in each group with three rabbits each). The first group served as a control and received 0.3 mL/kg BW of distilled water (CON), while the second and third groups received 0.3 mL/kg BW of rocket seed oil (RSO) and wheat germ oil (WGO), respectively. The fourth group received a mixture of oils consisting of 0.15 mL of RSO and 0.15 mL of WGO/kg BW (MOs). The experiment lasted 7 weeks. The study investigated the effects of RSO, WGO, and their mixture on growth performance, feed utilization, antioxidant status, and immune response of growing rabbits. The results indicated that the rabbits that were administered orally with RSO and WGO or their mixture had higher (p ≤ 0.05) final BW, weight gain, and average daily gain when compared to the control group. In addition, the feed conversion ratio improved significantly with RSO, WGO, and MOs treatments. Different oil treatments improved nutrient digestibility, nutritive value, and nitrogen balance. Moreover, the rabbits that received RSO, WGO, and their mixture had an improvement the meat fatty acid composition compared to the control rabbits. Oral administration of RSO, WGO, and their mixture significantly improved serum protein fractions, decreased blood urea nitrogen, and had a positive effect on serum total lipids, HDL-c, and LDL-c. Furthermore, the treatments of RSO, WGO, and MOs had a significant improvement in the antioxidative status and immune response.

Bioactive peptide apelin rescues acute kidney injury by protecting the function of renal tubular mitochondria.

Mitochondrial dysfunction in proximal tubular epithelial cells is a key event in acute kidney injury (AKI), which is a risk factor for the development of chronic kidney disease (CKD). Apelin is a bioactive peptide that protects against AKI by alleviating inflammation, inhibiting apoptosis, and preventing lipid oxidation, but its role in protecting against mitochondrial damage remains unknown. Herein, we examined the protective effects of apelin on mitochondria in cisplatin-stimulated human renal proximal tubular epithelial cells and evaluated its therapeutic efficacy in cisplatin-induced AKI mice. In vitro, apelin inhibited the cisplatin-induced mitochondrial fission factor (MFF) upregulation and the fusion-promoting protein optic atrophy 1 (OPA1) downregulation. Apelin co-treatment reversed the decreased levels of the deacetylase, Sirt3, and the increased levels of protein acetylation in mitochondria of cisplatin-stimulated cells. Overall, apelin improved the mitochondrial morphology and membrane potential in vitro. In the AKI model, apelin administration significantly attenuated mitochondrial damage, as evidenced by longer mitochondrial profiles and increased ATP levels in the renal cortex. Suppression of MFF expression, and maintenance of Sirt3 and OPA1 expression in apelin-treated AKI mice was also observed. Finally, exogenous administration of apelin normalized the serum level of creatinine and urea nitrogen and the urine levels of NGAL and Kim-1. We also confirmed a regulatory pathway that drives mitochondrial homeostasis including PGC-1α, ERRα and Sirt3. In conclusion, we demonstrated that apelin ameliorates renal functions by protecting tubular mitochondria through Sirt3 upregulation, which is a novel protective mechanism of apelin in AKI. These results suggest that apelin has potential renoprotective effects and may be an effective agent for AKI treatment to significantly retard CKD progression.

Development and Characterization of Functional Starch-Based Films Incorporating Free or Microencapsulated Spent Black Tea Extract.

Antioxidant polyphenols in black tea residue are an underused source of bioactive compounds. Microencapsulation can turn them into a valuable functional ingredient for different food applications. This study investigated the potential of using spent black tea extract (SBT) as an active ingredient in food packaging. Free or microencapsulated forms of SBT, using a pectin–sodium caseinate mixture as a wall material, were incorporated in a cassava starch matrix and films developed by casting. The effect of incorporating SBT at different polyphenol contents (0.17% and 0.34%) on the structural, physical, and antioxidant properties of the films, the migration of active compounds into different food simulants and their performance at preventing lipid oxidation were evaluated. The results showed that adding free SBT modified the film structure by forming hydrogen bonds with starch, creating a less elastic film with antioxidant activity (173 and 587 µg(GAE)/g film). Incorporating microencapsulated SBT improved the mechanical properties of active films and preserved their antioxidant activity (276 and 627 µg(GAE)/g film). Encapsulates significantly enhanced the release of antioxidant polyphenols into both aqueous and fatty food simulants. Both types of active film exhibited better barrier properties against UV light and water vapour than the control starch film and delayed lipid oxidation up to 35 d. This study revealed that starch film incorporating microencapsulated SBT can be used as a functional food packaging to protect fatty foods from oxidation.

Effect of rosemary extract and vitamin e on lipid peroxidation and the quality during chilling and frozen storage of fried Nile tilapia fillets (Oreochromis niloticus)

Antioxidants are added to fresh and processed meat to prevent lipid oxidation, retard development of off-flavors, and improve color stability. In the food industry, they can be divided into natural and synthetic antioxidants. Synthetic antioxidants have been confirmed for their toxicological and carcinogenic effects. Thus, the food industry now chooses natural products over synthetic ones. This study was carried out to investigate the effect of Rosemary extract (R.E.) and vitamin E on the quality of fried fillets of Nile tilapia (Oreochromis niloticus) during chilling and frozen storage. Fillets of Nile tilapia were treated with (R.E.) 0.1%, 0.2%, 0.3% and Vitamin E 0.1% then stored for 5,10 and 15 days at 4±1°C and for three months at -18±2°C. Then chemical tests including Peroxide value (PV), Thio-barbituric acid (TBA), Tri-methylamine-nitrogen (TMA-N) and Total volatile base-nitrogen (TVB-N) were done to evaluate the preservative effect of (R.E.) and vitamin E during storage. The TBA and PV increased in all treatments due to lipid peroxidation. Results showed that TMA-N,TVB-N, value of (R.E.) and vitamin E treated samples were significantly lower than those of the control samples (P<0.05). Results of our investigation revealed that R.E. retarded oxidative changes in chilling and frozen fried fillets of Nile tilapia whereas R.E. 0.1%, 0.2% and vitamin E 0.1% were not as effective as R.E. 0.3% on oxidative stability. Best oxidation inhabitation results on chilling and frozen fried fillets of Nile tilapia was obtained when employing of R.E. The obtained results also showed that there was a significant (p<0.05) enhancement in sensory quality attributes of fried fillets of Nile tilapia; samples treated with R.E. and vitamin E Conclusion: The tested R.E. had a high effectiveness as antioxidative and antimicrobial should be utilized for extending the shelf-life through retarded the spoilage and enhancing quality attributes of fried fillets of Nile tilapia during chilling and frozen storage.

Identification and characterization of extracellular enzymes secreted by Aspergillus spp. involved in lipolysis and lipid-antioxidation during katsuobushi fermentation and ripening

A mild-flavored soup stock made from katsuobushi is an important element of traditional Japanese cuisine and is the basic seasoning responsible for the taste. Fermented and ripened katsuobushi, known as karebushi, is manufactured by simmering skipjack tuna that is then smoke-dried, fermented, and ripened in a repeated molding process by five dominant Aspergillus species. Here, our aim was to characterize and identify the lipolytic enzymes secreted by the dominant Aspergillus species, especially A. chevalieri and A. pseudoglaucus, which are involved in hydrolyzing lipids during the molding process. The crude enzyme preparations from the five Aspergillus spp. cultivated on katsuobushi solid medium hydrolyzed triglycerides in fish oil, and more saturated and unsaturated fatty acids (C16:0, C16:1, C18:0, C18:1) were produced than major polyunsaturated fatty acids (C20:5, C22:6). On the basis of ion exchange chromatograms, the composition of the lipolytic enzymes was different in the five species. There was at least one active fraction with high hydrolytic activity toward fish oil in four of the Aspergillus spp., but not A. sydowii; the lipolytic enzyme secreted by A. sydowii had quite high activity toward the artificial substrate p-nitrophenyl butyrate, but low activity toward the natural oil. The lipolytic fractions from A. chevalieri and A. pseudoglaucus were further purified by hydrophobic interaction chromatography then gel-filtration chromatography; LC-MS-MS Mascot analysis identified a variety of lipolytic enzymes, including cutinase, esterase, phospholipase, and carboxyl esterase in the lipolytic fractions from these species. The identified enzymes had 30%–70% identity to previously reported or manually annotated lipases or esterases from taxa other than Aspergillus. The different lipolytic enzymes likely acted on triglycerides in the katsuobushi fish oil. Furthermore, catalase B and Cu/Zn superoxide dismutase, which limit oxidative damage of lipids, were also identified. These antioxidant enzymes may prevent lipid oxidation and rancidity as the lipolytic enzymes hydrolyze lipids during the long fermentation and ripening process. Umami and richness tastes tended to increase in extracts from culture of protease- and peptidase-producing A. sydowii. Our results will aid in the selection and application of desirable strains of Aspergillus species as starter cultures to improve the storage and quality of fermented and ripened karebushi.

Continuous production of monoacylglycerol via glycerolysis of babassu oil by immobilized Burkholderia cepacia lipase in a packed bed reactor.

This study investigated the glycerolysis of babassu oil by Burkholderia cepacia lipase immobilized on SiO2-PVA particles in a continuous packed bed reactor. Experiments were conducted in a solvent-free system at 273.15K either in an inert atmosphere or in the presence of cocoa butter to prevent lipid oxidation. The reactor (15 × 55mm) was run at a fixed space time of 9.8h using different molar ratios of babassu oil to glycerol (1:3, 1:6, 1:9, 1:12, and 1:15) to assess the effects of reactant molar ratio on monoacylglycerol productivity and selectivity. Nitrogen atmosphere and cocoa butter were equally effective in inhibiting lipid oxidation, indicating that addition of cocoa butter to glycerolysis reactions may be an interesting cost-reduction strategy. An oil/glycerol molar ratio of 1:9 resulted in the highest productivity (52.3 ± 2.9mgg-1h-1) and selectivity (31.5 ± 1.8%). Residence time distribution data were fitted to an axial dispersion model for closed-vessel boundary conditions, giving a mass transfer coefficient (kc) of 3.4229 × 10-6ms-1. A kinetic model based on elementary steps of the studied reaction was written in Scilab and compared with experimental data, providing standard deviations in the range of 5.5-7.5%.

Effect of chitosan coating incorporated with oregano or cinnamon essential oil on the bacterial diversity and shelf life of roast duck in modified atmosphere packaging

The present study aimed to investigate the effect of chitosan edible coating containing 0.15% oregano essential oil (OEO) or 0.60% cinnamon essential oil (CEO) on the quality characteristics and dynamic changes in the bacterial community of roast duck slices under modified atmosphere packaging (MAP, 30% CO2/70% N2) during 21 days of storage at 2 ± 2 °C. The results showed that the application of chitosan coating (CH) alone inhibited the growth of microorganisms and prevented lipid oxidation throughout storage. Moreover, the storage stability was further improved by including OEO or CEO, which lowered (P < 0.05) values for total viable count (TVC), Enterobacteriaceae, 2-thiobarbituric acid reactive substance (TBARS) and total volatile basic nitrogen (TVB-N). Based on the microbiological results, the shelf-life of CH-OEO and CH-CEO treated roast duck slices was prolonged by at least 7 days compared to that of the control. In addition, packaging types applied in this study played a major role in the bacterial community development. Notably, Vibrio spp. were the most predominant bacteria in all samples, when TVC values approached the shelf-life threshold, suggesting that this bacterium may be the main contributor to the spoilage of roast duck. The growth inhibition of Vibrio spp. in the CH-OEO and CH-CEO treatments during the early period of chilled storage might be the reason for the extension of the shelf life. Taken together, CH incorporated with OEO or CEO could be developed as prospective edible packaging materials to preserve roast duck meat.

Pangasius Catfish Feeding with Flammulina velutipes Extract Decreases the Disease Ratio, Prevents Lipid Oxidation, Structure Damage and Color Changes during Cool Preservation

ABSTRACT The effect of dietary supplementation of Flammulina velutipes concentrated extract (CE) on catfish fillet quality under cool preservation was evaluated. The catfish were fed by feed supplementing with 0% to 15% CE during the growth phase. After 30 days, the fish were filleted and stored at 4 ± 0.2°C for 7 days. The results showed that with 10% CE, the fish produced the best growth performance from 605 to 1106 g, corresponding to the lowest disease rate of 1.5%. Ergothioneine in muscle reached the highest value at 20.63 ± 1.35 mg/Kg. During the preservation, ergothioneine, 2,2-Diphenyl-2-picrylhydrazyl (DPPH) and lipid decreased slightly while free fatty acid (FFA) increased gradually until day 7. Peroxide and thiobarbituric acid reactive substances increased slowly after 7 days to 0.90 and 0.55 mg/Kg MDA, respectively. The b* value and total color variation (∆E) showed the slowest increase of −0.21 ± 0.67 and 46.85 ± 0.97, respectively, while the a* value decreased gradually during storage. pH decreased slightly on day 1, then increased to 6.4 ± 0.2 on day 7. The fillet was firmer on day 1, then decreased gradually in all treatments. Therefore, an increasing ergothioneine in catfish muscle leads to higher growth performance with a low disease rate and helps to prevent lipid oxidation, improving color and structural stability.

Enhancing oxidative stability of frying oils by low‐frequency radio wave treatment

SummaryRadio wave treatment (approximately 50 kHz frequency) on the oxidative stability was evaluated in corn oil at 180 °C and chicken frying oil for 150 cycles. Radio wave treatment decreased moisture content and critical micelle concentration of lecithin in corn oil. Moisture content in frying oil remained higher when radio wave was treated for the first 30 frying cycles. Radio wave treatment prevented lipid oxidation significantly in corn oil heated at 180 °C when moisture was not added (P &lt; 0.05). p‐Anisidine value and total polar material in chicken frying oils treated with radio waves were significantly lower than those of frying oils without radio wave treatment (P &lt; 0.05). Radio wave treatment enhanced the stability of tocopherols in corn oil heated at 180 °C in the absence of moisture, while the reverse result was observed with moisture addition. Overall, radio wave treatment can be a useful tool to enhance the oxidative stability of frying oils by modifying their moisture content and tocopherol stability.

High Metal Chelating Properties from Rapeseed Meal Proteins to Counteract Lipid Oxidation in Foods: Controlled Proteolysis and Characterization

AbstractRapeseed meal proteins (RP) are enzymatically hydrolyzed using three individual proteases (Alcalase, Flavourzyme, and Prolyve) and the enzymatic mechanism is studied. Rapeseed hydrolysates are produced under controlled conditions and the Prolyve hydrolysate is separated by membrane filtration. Their capacity to reduce free radicals (by transfer of hydrogen or electron) or transition metals (by electron transfer) in the absence of an oxidizable substrate, their metal chelating capacity as well as the antioxidant performances in model (conjugated autoxidizable triene assay) are investigated. All hydrolysates show a reduction capacity (by transfer of hydrogen or electron) and antioxidant activities, in a dose‐dependent manner, which are however not significantly increased in comparison to the native proteins. A noteworthy metal chelating activity of the peptides produced with Prolyve is highlighted. These results indicate the potential of valorization of RP as a source of high metal chelating peptides to counteract lipid oxidation in foods. Practical applications: Over the last decade, the antioxidative potential of peptides from plant biomass has been evidenced by much research. Considering the myriad of possible sources and the diversity of technology and means to obtain peptides from protein materials, it is reasonable to expect more applications. Concomitantly, preventing lipid oxidation, especially with the polyunsaturated fat‐based products, is a major concern in sectors such as agri‐food and cosmetic. Although the efficacy of synthetic antioxidants is recognized, both consumers and manufacturers are looking for more innovative, healthy, environmental‐friendly processes and quality products. In this context, a controlled proteolysis of proteins from plant by‐products can be used as a sustainable strategy to produce antioxidant peptides. Among them, new peptides released from rapeseed proteins with Prolyve can provide interesting metal chelators to counteract lipid oxidation in foods.

Characterisation of Conciato Romano: one of the oldest Italian cheeses

Conciato Romano is believed to be the oldest Italian ewe cheese; it is manufactured according to an unusual technology, ending with a long ripening in earthenware jars. Cheese was monitored during production and ripening in two different seasons: winter and spring. According to the data obtained, the ripening in jars prevents lipid oxidation, and ensures the safety of the product. Coagulase-positive staphylococci, Salmonella and Listeria spp. were never retrieved, while Enterobacteriaceae and Escherichia coli disappeared during the ripening, likely due to the antimicrobial activity of the tanning of the cheeses. Mesophilic lactic acid bacteria dominated the entire production process, with Lactiplantibacillus plantarum subsp. plantarum and enterococci accounting for about 26% and 30%, respectively, of the total cultures isolated (203). Total monounsaturated fatty acids and ω-3 and ω-6 polyunsaturated fatty acids were higher in cheeses produced during spring, while the atherogenic index was significantly lower. Outcomes of texture analysis confirmed seasonal differences, stressing the role of the animals’ feeding regimen.

Fish oil-gelatin core-shell electrospun nanofibrous membranes as promising edible films for the encapsulation of hydrophobic and hydrophilic nutrients

In this work, fish oil-gelatin core-shell electrospun nanofibrous membranes (ENMs) were explored as edible films for the encapsulation of hydrophobic fish oil and hydrophilic vitamin C (VC). The results demonstrated that fish oil-VC/gelatin core-shell ENMs could be successfully fabricated by a monoaxial emulsion electrospinning technique. The addition of VC didn't change core-shell structure but increased fragility of nanofibers. Excessive VC/gelatin mass ratios (≥4:20) increased the nanofiber adhesiveness during the storage at room temperature. No obvious chemical interactions occurred among fish oil, gelatin, and VC in the core-shell ENMs. VC addition decreased the loading capacity and had no obvious effects on encapsulation efficiency of fish oil in the ENMs. VC not only prevented lipid oxidation but also converted lipid hydroperoxides to other products during the electrospinning process. Fish oil-VC/gelatin core-shell ENMs were not disintegrated in ultrapure water but were disintegrated into particles in both gastric and intestinal fluids. The fish oil release from fish oil-VC/gelatin core-shell ENMs and disintegrated particles in the simulated intestinal phase of the gastrointestinal tract model and in the simulated intestinal model showed triphasic behaviors. This work provided a potential route to develop functional foods with encapsulation of both hydrophobic and hydrophilic nutrients.

Effect of green tea and rosemary extracts on shelf-life of salted lamb patties

Two commercial antioxidant extracts (GUARDIAN TM 75, rosemary and GUARDIAN TM Green Tea Extract 20S) were evaluated for their antioxidant efficacy in lamb burgers preserved at 2 o C for 9 days. A total of 9 kg of minced meat was used, making the patties in 3 replicates. In each replication, 3 Kg of meat were used, which were divided into 1 kg portions, which were mixed in a buffer solution by adding 0,15 M NaCl for each treatment: 1) Control, 2) 400 ppm of extract green tea and 3) 800 ppm rosemary extract respectively. Lamb patties containing 400 and 800 ppm of green tea and rosemary respectively prevented lipid oxidation, evaluated by the TBARS technique (P <0,05). Green tea at 400 ppm prevented discoloration, stabilizing the values of a * (red index) and the C * value (color intensity) of unprocessed patties during storage (p <0,05) These results indicated that green tea and rosemary extract were effective in inhibiting lipid oxidation and green tea preserves red color of raw lamb patties during aerobic and refrigerated storage.

Effect of Rosemary Extract and Vitamin E on Lipid Peroxidation and the Quality During Chilling and Frozen Storage of Fried Nile Tilapia Fillets (Oreochromis niloticus)

Antioxidants are added to fresh and processed meat to prevent lipid oxidation, retard development of off-flavors, and improve color stability. Synthetic antioxidants have been confirmed for their toxicological and carcinogenic effects. Thus, the food industry now chooses natural products over synthetic ones. This study was carried out to investigate the effect of Rosemary extract (R.E.) and vitamin E on the quality of fried fillets of Nile tilapia (Oreochromis niloticus) during chilling and frozen storage. Fillets of Nile tilapia were treated with (R.E.) 0.1%, 0.2%, 0.3% and Vitamin E 0.1% then stored for 5,10 and 15 days at 4±1°C and for three months at -18±2°C. Then chemical tests including Peroxide value (PV), Thio-barbituric acid (TBA), Tri-methylamine-nitrogen (TMA-N) and Total volatile base-nitrogen (TVB-N) were done to evaluate the preservative effect of (R.E.) and vitamin E during storage. The TBA and PV increased in all treatments due to lipid peroxidation. Results showed that TMA-N,TVB-N, value of (R.E.) and vitamin E treated samples were significantly lower than those of the control samples (P&lt;0.05). Results of our investigation revealed that R.E. retarded oxidative changes in chilling and frozen fried fillets of Nile tilapia whereas R.E. 0.1%, 0.2% and vitamin E 0.1% were not as effective as R.E. 0.3% on oxidative stability. Best oxidation inhabitation results on chilling and frozen fried fillets of Nile tilapia was obtained when employing of R.E. The obtained results also showed that there was a significant (p&lt;0.05) enhancement in sensory quality attributes of fried fillets of Nile tilapia; samples treated with R.E. and vitamin E. Conclusion, The tested R.E. had a high effectiveness as antioxidative and antimicrobial should be utilized for extending the shelf-life through retarded the spoilage and enhancing quality attributes of fried fillets of Nile tilapia during chilling and frozen storage.

Ergothioneine accumulated in the catfish muscle by supplementation of Flammulina velutipes extract prevents lipid oxidation, improves color stability, and limits soft structure of the fillet during frozen storage

This study aimed to evaluate whether ergothioneine (ESH) accumulated in catfish muscle affected to fillet quality during frozen storage. The fish after fed by feed supplemented 0 to 15% concentrated extract (CE) from Flammulina velutipes for 30 days were filleted and stored at −18 ± 0.2°C for 90 days. The results show that with 10% CE, the highest accumulation of ESH in fish muscle was 21.02 mg/Kg. During preservation, ESH decreased gradually with DPPH. Peroxide and FFA were the lowest value at 1.09 meq/Kg and 0.35% on day 90, respectively. L* achieved lower while a* and b* values were quite stable during the first 60 days. The a* dropped slightly, but the b* and ∆E increased slowest from days 60 to 90. The muscle hardness was more stable during storage. Therefore, high accumulation of ESH in catfish muscle could prevent lipid oxidation, improving color stability, and limit soft structure during frozen storage. Novelty impact statement The Pangasius processing industry in the Mekong Delta depends on the catfish harvest time point and export demand, so it usually needs 1 to 3 months preservation in the freezer in which the quality of the fillet may be changed. The results from this study indicated that the highest ESH accumulation corresponding to 10% CE of F. velutipes supplemented with feed for 30 days feeding showed the most effectiveness during 90 days preservation in terms of limiting lipid oxidation, preventing discoloration, and making the fish structure less soft after thawing from frozen storage. Therefore, the supplementation of F. velutipes during feeding shows a great solution for improving catfish fillet quality during frozen storage.

Oxidative stability of chia seed oil and flax seed oil and impact of rosemary (Rosmarinus officinalis L.) and garlic (Allium cepa L.) extracts on the prevention of lipid oxidation

Chia seed and flax seed oils are rich in polyunsaturated fatty acids, but are susceptible to oxidative deterioration. The aim of this study was to determine the oxidative stability of chia seed and flax seed oils and enhance the stability using rosemary or garlic extracts. During accelerated storage at 65 °C for 14 days, the antioxidant abilities of rosemary or garlic extracts were evaluated and compared with those of butylated hydroxy toluene, ascorbyl palmitate, and α-tocopherol using peroxide value, conjugated dienoic acids, free fatty acid, thiobarbituric acid value analysis. The profile of volatiles, fatty acid composition, and the tocopherol contents in the treated and/or untreated oils were also determined. Active ingredients of rosemary and garlic extracts were also determined. Rosemary extract was found to provide higher oxidative stability than garlic extract after 14 days in most assays (e.g., the CDA values of 4.8% for rosemary extract and 5.2% for garlic extract in chia seed oil). The contents of γ-tocopherol, linoleic acid, and α-linolenic acid were well retained in the functional oils treated with the two extracts. After accelerated storage, the content of the major odor-active volatiles varied based on the type of oil. Our findings show the potential of natural aromatic plant extracts with respect to improving the oxidative stability of functional oils.