Reduced Lipid Oxidation Research Articles

Protective effects of Bacillus velezensis on texture, physicochemical properties, and lipid oxidation of grass carp fillets during repeated freeze-thaw cycles.

Probiotics have excellent antioxidant and antibacterial effects and are also considered to be promising natural biological preservatives. This study examined the freeze-thaw stability of the antioxidant and antibacterial activity of probiotic Bacillus velezensis PJP10, and evaluated the effect of different concentrations of PJP10 (106, 107, and 108 CFU mL-1) on microbial growth, textural characteristics, physicochemical properties, and lipid oxidation of grass carp fillets during repeated freeze-thaw cycles. Freeze-thaw cycles had little effect on the antioxidant and antibacterial stability of PJP10. Treatment with the PJP10 strain slowed effectively the increase in Aeromonas spp. counts (ASC), pH, total volatile basal nitrogen (TVB-N), and thiobarbituric acid (TBA) values of the freeze-thaw fish fillets. It maintained the textural quality of fillets, inhibiting the reduction of hardness, springiness, gumminess, cohesiveness, chewiness, and resilience values, and reduced lipid oxidation, as evidenced by decreased carbonyl values and conjugated diene values after multiple freeze-thaw cycles. Probiotic B. velezensis PJP10 had protective effects on microbiological, textural, and physicochemical properties, and lipid oxidation of grass carp fillets during repeated freeze-thaw storage, suggesting a potential application of this strain in the freeze-thaw preservation of freshwater fish. © 2024 Society of Chemical Industry.

Impacts of carob pulp (Ceratonia siliqua L.) and vitamin E on pork colour, oxidative stability, lipid composition and microbial growth

This study aimed to evaluate the impact of the dietary by-product rich in polyphenols (Carob pulp, Cp) and supra-nutritional level of vitamin (Vit) E on pork quality and shelf-life of meat stored in modified atmosphere packaging for 15 days. A total of 44 pigs (entire males and gilts, 170 ± 4.5 days of age and 127.8 ± 3.6 kg of body weight) were randomly selected from a larger group (one pig per pen). Pigs were fed ad libitum with one of four diets in a 2 × 2 factorial arrangement, with two feed inclusion levels each for Cp (0 vs. 20 %) and Vit E (30 (Low) vs. 300 IU/kg of feed (High)) for 40 days. No interactions between Cp and Vit E were detected for most variables assessed. Meat colour attributes evolved regardless of diet or sex, although metmyoglobin formation was preserved until 13 days. The Cp diets did not affect malondialdehyde nor α-tocopherol content in meat. High Vit E limited the malondialdehyde production up to 13 days and increased 1.8-fold the muscle α-tocopherol content compared to Low Vit E. The 20 %-Cp group tended to reduce total aerobic microbial count compared to 0 %-Cp group after 15 days of storage. Including Cp slightly affected the meat fatty acid (FA) profile, whereas Vit E did not modify it. Entire males presented higher content of polyunsaturated FA than gilts. Including 20 % Cp into pigs' diets does not impair meat quality, while High Vit E reduces lipid oxidation but not meat discolouration.

Alginate-based edible coating with magnoliae essential oil/β-cyclodextrin inclusion complex for Kyoho grape preservation

To prolong the shelf life of Kyoho grapes at room temperature, an edible coating composed of sodium alginate (SA) containing an inclusion complex of Magnoliae essential oil (MEO) and β-cyclodextrin (β-CD) (SA/MEO@β-CD coating) was developed. Initially, the inclusion complex of MEO with β-CD was developed to enhance its thermal stability. MEO@β-CD was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). In addition, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) results show that β-CD can improve the thermal stability of MEO. The entrapment efficiency and loading efficiency were 82.56% and 8.8%. MEO@β-CD was added to the SA coating for preserving Kyoho grapes, while monitoring the enzyme activity, total bacterial count, and sensory characteristics of the grapes. Compared to the uncoated group, the SA/MEO@β-CD coated group exhibited a significant reduction in total color difference, decay rate, weight loss rate, enzyme activity, and total number of bacterial colonies, while also slowing the decline in hardness and total soluble solids. The effect of the SA/MEO@β-CD1 group was highly effective. Conclusively, the SA/MEO@β-CD coating preserves Kyoho grapes by reducing lipid oxidation and inhibiting microbial growth, demonstrating its potential as an advanced edible packaging solution for grape preservation.

The effect of mechanical glass transition temperature on the oxidation rates of omega fatty acids in condensed biopolymer matrices

The concept of glass transition has been used in food products to study their stability, extending shelf life and enhancing organoleptic desirability. This investigation evaluates the effect of three-dimensional structure as a barrier to oxidation of omega fatty acids in condensed hydrocolloid-based matrices. Two high-solid preparations were employed: κ-carrageenan with glucose syrup and genipin-crosslinked gelatin with polydextrose. They supported discontinuous microscopic inclusions of linoleic and linolenic acids within the rubber-to-glass transition region of the condensed mixtures. Glass transition temperatures (Tg) were estimated using differential scanning calorimetry and in-shear dynamic oscillation. The rate of lipid oxidation was monitored by analysing hydroperoxide (ROOH) production during each oxidation phase. The structural transformation of the supporting matrices as a function of temperature significantly affects the oxidation processes. The mechanical or network Tg exhibited higher values than the calorimetric Tg, supporting reduced lipid oxidation rates by suppressing ROOH accumulation in the densified glassy matrices.

Montmorillonite nanoclay triggers immunity responses in wheat against Puccinia striiformis f. sp. tritici, and suppresses uredospore germination

Puccinia striiformis f. sp. tritici causes the important disease, yellow rust of wheat (Triticum aestivum). Montmorillonite nanoclay (MNC) is naturally occurring and biodegradable. This study assessed in vitro anti-germination effects of MNC on P. striiformis uredospores. Application of MNC at 150 mg L-1 completely inhibited uredospore germination, and MNC at 100 mg L-1 reduced yellow rust severity in wheat plants by 89%. Expression of defense-related genes was increased after MNC treatment at 100 mg L-1, by 5.23-fold for jasmonate and ethylene-responsive factor 3 (JERF3), 4.89-fold for chitinase class II (CHI II), and 2.37-fold for pathogenesis-related protein 1 (PR1). Applying MNC at 100 mg L-1 also activated the antioxidant enzymes POD to 62.1 unit min-1 g-1 fresh wt, PPO to 21.6 units min-1 g-1 fresh wt, and CAT to 36.6 units min-1 g-1 fresh wt. MNC also enhanced phenolic content in wheat leaves (to 1489.53 mg 100 g-1 f. wt), and reduced lipid oxidation levels (to 5.6 μmol MDA g-1 fresh wt). MNC at 100 mg L-1 also mitigated damaging effects of P. striiformis infections on host leaf cell ultrastructure, increased leaf photosynthetic pigments, and increased wheat plant growth. These results show that MNC has potential as a natural control agent for yellow rust of wheat, although field testing of MNC is necessary before this material can be recommended for wheat production.

An intrinsic mechanism of metabolic tuning promotes cardiac resilience to stress

Defining the molecular mechanisms underlying cardiac resilience is crucial to find effective approaches to protect the heart. A physiologic level of ROS is produced in the heart by fatty acid oxidation, but stressful events can boost ROS and cause mitochondrial dysfunction and cardiac functional impairment. Melusin is a muscle specific chaperone required for myocardial compensatory remodeling during stress. Here we report that Melusin localizes in mitochondria where it binds the mitochondrial trifunctional protein, a key enzyme in fatty acid oxidation, and decreases it activity. Studying both mice and human induced pluripotent stem cell-derived cardiomyocytes, we found that Melusin reduces lipid oxidation in the myocardium and limits ROS generation in steady state and during pressure overload and doxorubicin treatment, preventing mitochondrial dysfunction. Accordingly, the treatment with the lipid oxidation inhibitor Trimetazidine concomitantly with stressful stimuli limits ROS accumulation and prevents long-term heart dysfunction. These findings disclose a physiologic mechanism of metabolic regulation in the heart and demonstrate that a timely restriction of lipid metabolism represents a potential therapeutic strategy to improve cardiac resilience to stress.

Effect of flaxseed oil cyclolinopeptides on lipid oxidation, protein oxidation, and lipid profile during in vitro digestion of high-fat beef

This study investigated the influence of flaxseed oil cyclolinopeptides (CLs) on lipid and protein oxidation during high-fat meat digestion. Fourteen CLs were identified in flaxseed oil through UHPLC-ESI-QTOF-MS/MS, with dominant CLA, CLB, CLE, and CLM. During in vitro digestion, CLs inhibited lipid oxidation products (lipid hydroperoxide, Malondialdehyde, and 4-hydroxynonenal) and protein carbonylation. Compared to other groups, the lipid (16.28 ± 0.35) and protein (17.5 ± 0.6) oxidation was significantly inhibited, and antioxidant activity was remarkably increased when the CLs content reached 200 mg/kg. Through untargeted lipidomic analysis using Q-Exactive, it was observed that CLs mitigated the formation of oxidized triglycerides (OxTG) products and enhanced the hydrolysis of lipids to generate sphingolipid and polyunsaturated fatty-acids enriched glycerophospholipids imparting nutritional value to meat. Electron spin-resonance and fluorescence quenching showed that primary radicals such as alkyl and alkoxy radicals during high-fat meat digestion with flaxseed oil CLs significantly mitigate their formation. These findings collectively indicate that consuming CLs enriched flaxseed oil could reduce lipid oxidation and enhance the nutritional value of high-fat meat during digestion.

Effect of Near-Freezing Storage Combined with High-Voltage Electric Fields on the Freshness of Large Yellow Croaker.

Seafood is highly perishable after being caught, making effective preservation technology essential. A few studies have explored the mechanisms of near-freezing storage combined with high-voltage electric fields for seafood preservation. This study uses near-freezing storage at -1 °C in conjunction with three high-voltage electric fields (5 kV/m, 8 kV/m, and 16 kV/m) to store large yellow croakers for 21 days and assesses their quality through sensory evaluation, pH values, malondialdehyde, total volatile basic nitrogen, and total viable counts. The results indicate that high-voltage electric fields effectively inhibit endogenous enzyme activity and microbial growth while reducing lipid oxidation in large yellow croakers. The preservation effect is optimal at an electric field strength of 16 kV/m, extending their shelf life by 9 days. These findings offer valuable theoretical and data-driven insights for applying near-freezing storage and electric field preservation technology in cross-regional fish transportation.

Using palm oil residue for food nutrition and quality: from palm fatty acid distillate to vitamin E toward sustainability.

Increasing global palm oil production yields a valuable palm fatty acid distillate (PFAD) - a rich vitamin E (Vit-E) source and multifunctional ingredient in the food agro-industry - that can be utilized to achieve sustainability. This article reviews trends in the use and role of PFAD and its Vit-E in the food sector and proposes an integrated agro-industrial concept toward sustainability. Vit-E can be separated from PFAD with diverse and impactful pharmaceutical activities, including antioxidant, anti-inflammatory, anticancer and anti-ultraviolet effects. Based on in vivo experimental tests, PFAD and Vit-E supplementation can enhance the productivity and quality of livestock-based food products. PFAD is a plasticizer and antistatic packaging material in food packaging systems, and its derivatives can be used as food additives. Meanwhile, the Vit-E molecule in packaging can extend food shelf life by maintaining color stability, reducing lipid oxidation and rancidity, adding antimicrobial properties, and influencing changes in packaging properties such as water vapor, tensile strength, melting point and other physical properties. Toward sustainability, an integrated agro-industrial design has been proposed to implement clean production, increase the added value of palm oil industry residues, minimize environmental risks and increase profits to achieve long-term social welfare. In conclusion, PFAD residues and their Vit-E content have shown broad benefits in the food sector and prospects toward sustainability. © 2024 Society of Chemical Industry.

Antibacterial Activity and Mechanism of Lauric Acid Against Staphylococcus aureus and Its Application in Infectious Cooked Chicken.

Staphylococcus aureus contamination and prevention has always been a major concern for food industry. This work investigated the antibacterial activity and mechanisms of lauric acid (LA) against S. aureus. Results revealed 156 μg/mL was the minimum inhibitory concentration (MIC) for LA and it retarded growth rate of S. aureus. The inhibitory effect was enhanced with LA concentration. After being treated with 2 MIC LA for 24 h, the number of S. aureus decreased by 3.56 log colony-forming unit (CFU)/mL. Scanning electron microscopy profiling revealed that LA resulted in altered morphology of S. aureus cells. In addition, propidium iodide staining of flow cytometry suggested that LA treatment disrupted the cell membrane integrity. Changes in 8-anilino-1-naphthalenesulfonic acid fluorescence indicated a depolarization change in cell membrane fluidity. For practical applications, LA also displayed an antimicrobial potential in cooked chicken food model system, with 1.25-5 g/L of LA prolonging shelf life by 2 days at 4°C. Moreover, it had no adverse effect on pH values, color in cooked chicken meat, and even reduced lipid oxidation. To sum up, LA has great antimicrobial properties and is a candidate preservative for cooked meat food.

Investigation on the structure and properties of nanostructured lipid carriers loaded with different contents of phytosterols and their impact on lipid oxidation

In this study, nanostructured lipid carriers (NLCs) were prepared using walnut oil as a liquid lipid to load phytosterols (PS). The effects of different ratios of PS to lipids on the structural and functional properties of these carriers and lipid oxidation of PS-loaded carriers were investigated. The XRD, FTIR, and DSC results indicated that NLCs formulated with walnut oil as the liquid lipid were successful in incorporating PS. These NLCs exhibited a smaller average particle size (<300 nm) and a lower PDI (<0.3), along with a higher zeta potential. Furthermore, transmission electron microscopy (TEM) revealed that PS5-NLC displayed the most uniform particle size distribution and excellent dispersion. Notably, NLCs demonstrate high encapsulation efficiency and antioxidant capacity. Importantly, the bioaccessibility of PS in the carriers significantly increased from 23.5% to 86.8% compared with that of pure PS. Following a storage period of 21 days, the NLCs loaded with PS showed a lipid hydroperoxide (LH) value of 32.4 mmol/L and a malondialdehyde (MDA) content of 9.9 μmol/L, which were 13.6% and 33.3% lower, respectively, than those of the carriers without PS, indicating an effective reduction in lipid oxidation. This study is first to introduce the innovative use of walnut oil as a liquid lipid for preparing NLCs. It was observed that incorporating PS not only enhanced the bioaccessibility of these compounds but also effectively mitigated lipid oxidation. Overall, this study offers valuable insights into the development of PS delivery systems and broadens the potential applications of walnut oil.

Antioxidant amyloid fibril derived from rice protein hydrolysate as stabilizer towards preparing high-stable emulsion

An antioxidant amyloid fibril was prepared as an emulsifier by fibrillating limited enzymatic hydrolysis-modified rice protein (HRP). The purpose of this study was to investigate the feasibility of using fibrillated HRP to stabilize oil-in-water emulsion. A free radical scavenging assay revealed that the antioxidant activity of fibrillated HRP was 2.09 times higher than that of native rice protein. Fibrillated HRP demonstrated a marked reduction in interfacial tension, increased surface hydrophobicity and contact angle (> 80°), and rapid adsorption to the interface, with 35.34 ± 2.43% interfacial adsorbed protein content. The fibrillated HRP barriers resisted environment stresses such as NaCl, pH variations, long-term storage, while reducing lipid oxidation degree. Additionally, fibrillated HRP-based emulsion was more effective in protecting β-carotene from degradation compared to other samples. These findings provide theoretical support for the development of rice protein-based antioxidant emulsifiers and modification of emulsifying properties of plant proteins.

Protective potential of onion eco-extract: safeguarding chicken patties from oxidative deterioration

ABSTRACT Onions contain valuable phytochemical compounds, including quercetin derivatives. This study explores the potential of onion extract as a natural additive in chicken patties. The optimized conditions involved sonication at 80% for 5 min with a 75% ethanol concentration. The onion extract exhibited total phenolic and flavonoid compound values of 255.63 mg GAE g−1 DR and 196.87 mg QE g−1 DR, respectively. The antioxidant activity of the onion extract was characterized by an IC50 of 12.74 µg/mL. This onion extract was dominated by quercetin derivatives (quercetin 4’-O-β-glycoside and quercetin-3-O-β-glycoside and quercetin-3,4’-O-β-diglycoside). Chicken patties treated with 2% onion extract exhibited superior pH stability, lowest thiobarbituric acid reactive substances level (0.40 mg/kg) and peroxide index (0.77 mEq O2/kg meat) and maintained color stability. Comparative analysis with BHT demonstrated the efficacy of onion extract in reducing lipid oxidation. These findings highlight the potential of a 2% onion extract as effective ingredient for enhancing the quality of chicken products.

Starch‐based and green tea extract films: characterisation and evaluation of the shelf life of interleaved sliced calabrese sausage

SummaryThis study aimed to develop and characterise cassava starch‐based films incorporating green tea extract and to assess the antioxidant effectiveness of these edible films against oxidative degradation in sliced calabrese sausage. The films were formulated with 3.5% starch (w/v) and 35% glycerol (w/w), with the addition of commercial green tea extract at concentrations of 1.0%, 2.5%, and 5.0% (w/v of film‐forming solution). The formulations with extract showed significantly higher per cent elongation at break compared to the control (without extract) (P &lt; 0.05), with higher tensile strength observed in the film with 1.0% extract. The best results in antioxidant activity kinetics with IC50 values between 0.012 and 0.14 mg mL−1 over 60 days were obtained with 1% of the extract. The cassava starch film with 1.0% extract inhibited the lipid oxidation of calabrese sausage for 18 days. The presence of 1.0% extract in the film reduces lipid oxidation in calabrese sausage without sensorial alteration, extending shelf life and suggesting it as an alternative to conventional plastics.

Fatty acid profile, physicochemical composition and carcass traits of young Nellore bulls fed Acacia mearnsii extract

Fatty acid profile, physicochemical composition, and carcass traits of 32 young Nellore bulls were assessed following the supplementation of Acacia mearnsii extract at levels of 0, 10, 30, and 50 g/kg of total dry matter (DM) in a completely randomized experiment with four treatments and eight replicates. Adding 50 g/kg DM of condensed tannins (CT) from Acacia mearnsii in the bulls' diet reduced DM intake, average daily gain, and meat lipid oxidation (P ≤ 0.05). The pH, centesimal composition, collagen, and meat color indexes of the longissimus muscle were not altered by the addition of Acacia mearnsii (P > 0.05). Cooling loss increased (P = 0.049) linearly. Including Acacia mearnsii in diet reduced the Warner-Bratzler shear force (WBSF, P = 0.018) of longissimus muscle of the bulls. The concentration of C16:0, C17:0, C24:0, t9,10,11,16–18:1, c9t11–18:2, C18:2n–6, C20:4n–6, 20:5n–3, 22:5n–3, and 22:6n–3 in the muscle increased due to the addition of Acacia in the diet (P ≤ 0.05), with the highest muscle concentrations caused by the addition of 10 to 30 g Acacia. c9–18:1 and t16–18:1 reduced linearly. ƩSFA, ƩBI, Ʃcis– and ƩMUFA, Ʃn–3, Ʃn–6, and ƩPUFA (P ≤ 0.05) quadratically increased at higher concentrations of addition of Acacia, above 30 g/kg DM. It is recommended to include Acacia mearnsii extract up to 30 g/kg total DM in diets for young bulls as it improves CLA, PUFA and TI and reduces lipid oxidation. Acacia mearnsii extract as source of CT at 50 g/kg DM negatively impacted the young bulls performance.

Evaluation biodegradable films with green tea extract for interleafing sliced meat products

A selection of formulations with different polymers and concentrations of green tea extract was conducted for application as interleafs in sliced meat products. Films were formulated using cellulose acetate, corn starch, and chitosan with the addition of 1.0, 2.5, and 5.0% green tea extract. Higher antioxidant activity was observed with the 1.0% concentration of green tea extract (P < 0.05), regardless of the formulation, with continuous release of the extract for up to 60 days and average IC50 of 0.09 and 0.31 mg/mL for the corn starch and chitosan active films, respectively. Interleafing the sliced ham resulted in lower lipid oxidation after 60 days of storage (P < 0.05). Starch-based films with green tea extract were effective, significantly reducing lipid oxidation in sliced and interleafed cooked ham, suggesting their potential to extend the shelf life of these refrigerated products.

Synergistic Effects of Salicylic Acid and Bacillus butanolivorans KJ40 for Enhancing Napa Cabbage (Brassica napa subsp. pekinensis) Resilience to Water-Deficit Stress

Climate change exacerbates drought, globally impacting crop production and necessitating the adoption of sustainable strategies. This study investigates the potential synergistic effects of salicylic acid (SA) and Bacillus butanolivorans KJ40 (KJ40) on napa cabbage (Brassica rapa subsp. pekinensis) under water-deficit stress conditions by watering withheld for five days. Results demonstrate that the combined application of KJ40 and SA, particularly at concentrations of 0.5 mM and 1 mM, significantly enhances plant growth and mitigates the negative impacts of water deficit. Moreover, the combination treatment with SA (0.5 mM) and KJ40 (1 × 108 cells/mL) reduces lipid oxidation and enhances antioxidant enzyme activity, indicating improved plant stress tolerance. Analysis of soil microbial profiles reveals alterations in metabolic activity and substrate utilization patterns, suggesting potential changes in rhizosphere dynamics. Additionally, this study examines the impact of SA on KJ40 population dynamics in soil, revealing concentration-dependent effects on bacterial survival. Overall, the combination of KJ40 and SA was effective in mitigating water-deficit stress in napa cabbage. These findings highlight the combination as a novel synergistic strategy to enhance plant resilience to water-deficit stress, offering insights into plant–microbe interactions and soil ecosystem dynamics.

Synergistic antioxidant and antibacterial activities of polyphenol extracts from mangosteen peels in preservation of Pangasius hypophthalmus fish balls

In recent years, natural preservatives have attracted more and more attention in food processing since they can enhance food shelf-life and safety. In this study, the polyphenol extract was obtained from mangosteen peels using enzyme-microwave assisted method, characterized for its antioxidant and antimicrobial activities and subsequently used as a natural additive in fish ball preservation. Results revealed that the mangosteen peel polyphenol powder (MPP) had a high phenolic content of 154 mg gallic acid equivalent/g dry matter, which led to high 2,2-diphenyl-1-picrylhydrazyl free radical scavenging capacity of 95 mg Trolox equivalent/g dry matter. MPP also exhibited effective antimicrobial activity against E. coli and S. aureus, expressed by its large inhibitory zones (11.3 and 12.1 mm, respectively) and small ratios (less than 4) of minimum bactericidal concentration over minimum inhibitory concentration against tested bacteria. The MPP supplementation at the levels of 38 mg/100 g and 53 mg/100 g into fish balls remarkably improved their gel strength, reduced lipid oxidation, limited protein oxidation and structural degradation as compared to those of the control without any addition or with synthetic preservatives. Especially, the addition of 53 mg MPP/100 g could sufficiently retard the microorganism growth. The synergistic effects of MPP in both antioxidant and antimicrobial activities hence could extend the shelf-life of fish balls, more than 40 %, as compared to butylated hydroxytoluene (synthetic antioxidant) or sodium benzoate (synthetic antimicrobial) with their single effects. These findings imply that MPP could be potentially used as a natural additive in preservation of fish and meat products.

Investigation of antioxidant edible coating and modified atmosphere packaging for enhancing storability of hazelnut kernels

This study investigated the effects of antioxidant edible coating and modified atmosphere packaging for improving storability of dried hazelnut kernels by delaying lipid oxidation and color degradation. Hazelnut kernels were coated with different coating matrix (methylcellulose and chitosan) that contain different antioxidant substances (DL-α-tocopherol acetate, cinnamon essential oil, rosemary essential oil and hazelnut oil) and subjected to an accelerated storage condition at 35 °C for 270 days. Hazelnut kernels were also packed under modified atmosphere (MAP) with 100 % N2 in mylar bags and stored at 35 °C for 180 days. Lipid oxidation (free fatty acids, K232 and K270, peroxide values) and color (browning index) were measured for investigating quality changes during the storage. The free fatty acids of kernels from two packaging experiments remained stable during storage. K232 value of MAP kernels was significantly lower (2.20) than that of control (2.90) at the end of the storage, showing delayed production of conjugated dienes. The chitosan based edible coating with encapsulated cinnamon essential oil and oleic acid (CH/ECO/OA) resulted in significantly (P < 0.05) lower PV values (0.53 meq/kg oil), and all the coated samples had the positive effect on reducing browning index with 12–25 compared with control. K270 (0.04–0.18) remained relatively low throughout the long-term storage. As a result, modified atmosphere packaging performed better than edible coatings. This study demonstrated the importance of implicating proper postharvest technology for reducing lipid oxidation and quality deteriorations of hazelnut kernels during prolonged storage.

Glucose addition and oven-heating of pork stimulate glycoxidation and protein carbonylation, while reducing lipid oxidation during simulated gastrointestinal digestion

In the present study, it was investigated if glucose addition (3 or 5%) to pork stimulates glycoxidation (pentosidine, PEN), glycation (Maillard reaction products, MRP), lipid oxidation (4-hydroxy-2-nonenal, 4-HNE; hexanal, HEX; thiobarbituric acid reactive substances, TBARS), and protein oxidation (protein carbonyl compounds, PCC) during various heating conditions and subsequent in vitro gastrointestinal digestion. An increase in protein-bound PEN level was observed during meat digestion, which was significantly stimulated by glucose addition (up to 3.3-fold) and longer oven-heating time (up to 2.5-fold) of the meat. These changes were accompanied by the distinct formation of MRP during heating and digestion of the meats. Remarkably, stimulated glyc(oxid)ation was accompanied by increased protein oxidation, whereas lipid oxidation was decreased, indicating these reactions are interrelated during gastrointestinal digestion of meat. Glucose addition generally didn't affect these oxidative reactions when pork was packed preventing air exposure and oven-heated until a core temperature of 75 °C was reached.