Decreased Lipid Oxidation Research Articles

Effect of Gelatin Coated Rosemary Extract (Rosmarinus Officinalis L.) on the Quality of Refrigerated Duck Meat

The effect of edible coating of gelatin (1, 2 and 3%) containing aqueous extract of rosemary (1% and 2%) on physiochemical (pH, total volatile nitrogen, peroxide values and water holding capacity) and microbiological (psychrotrophic) properties of duck fillet were evaluated. The pH of coated samples were significantly (plessthan0.05) lower than that of untreated sample. TVN (total volatile nitrogen) value increased with storage period in all the samples but coatings significantly decreased production of TVN compared to the control. Also the coatings decreased lipid oxidation of the meat as rosemary postponed primary oxidation of fillet, while this parameter in control group was sharply increased by time. WHC (water holding capacity) increased significantly (plessthan0.05) with storage period and level coatings. Coating had a significant reducing effect on growth of psychrotrophic bacteria during 9 days at 4°C. In conclusion, gelatin edible coating enriched with rosemary could retard chemical and microbial reactions related to spoilage of meat during refrigerated storage.

Lipid Oxidation and Color Stability of Spiced and Unspiced Pork Sausage with a Novel Antioxidant Mixture of Rosemary Extract and Phospholipase A2

ObjectivesThe objective of this study was to measure the loss of redness and onset of lipid oxidation in pre-rigor pork sausage containing synthetic antioxidants (Syn) compared to rosemary extract (R), and a combination of R with different concentrations of phospholipase A2 (R+P) over both light display and frozen storage.Materials and MethodsOur work examined pre-rigor spiced and unspiced pork sausage. Tissue from sows for both spiced and unspiced sausage was coarse ground and cooled to 1–3°C with dry ice within 1-h post-exsanguination. Water, treatments and seasonings were added, and the sausage stuffed within 2 h post-exsanguination for spiced sausages. Water and treatments were added 24 h post-exsanguination for the unspiced sausage. Sausages were stored in the dark at –20°C (to 110 and 245 d for unspiced and spiced, respectively) prior to light display. Sausages were sampled for color and lipid oxidation on approximately 40-d intervals of –20°C dark storage and 7–9 d of light display (5°C). In spiced sausage, R (type HT-P) was added at 200 ppm, PLA2 was added at 0.4 ppm. Butylated hydroxyanisole (BHA), propyl gallate (PG) and citric acid (CA) were each added at 0.01% of the estimated fat and collectively formed the Syn treatment. Spices consisted of sucrose, ginger, coriander, nutmeg, white pepper, and MSG. In unspiced sausage R was added at 200 ppm, PLA2 added at 0.4 ppm and 10 ppm, and BHA, CA and PG added at the same levels as in spiced sausage. Color stability was measured based on redness (a*). Peroxide values (PVs) were measured spectrophotometrically, headspace hexanal was measured via gas chromatography (GC) and α tocopherol depletion was measured with HPLC fluorescence detection as markers of lipid oxidation. Total lipids were fractionated to gravimetrically quantify neutral lipids, free fatty acids and polar lipids and to measure PVs in the aforesaid fractions. Unspiced sausages were only stored for 110 d because of rampant lipid oxidation and loss of color.ResultsIn spiced sausage, R and R+P displayed better color stability than both the control (no antioxidant, C) and Syn. Syn displayed the lowest hexanal values. R had the highest PVs and both Syn and R+P were significantly lower. Free fatty acids were the most heavily oxidized fraction on an oil basis, while neutral lipids were the most oxidized lipid on a wet weight basis. Alpha tocopherol did not deplete through 245 d in spiced sausage but was not detected in the unspiced sausage.In unspiced sausage, R+P was examined at two different levels (0.4 ppm and 10 ppm PLA2). R+P (10 ppm) exhibited lower headspace hexanal than R alone and R+P at both levels performed as well as Syn. In addition, R+P at both levels displayed significantly better color stability than R alone and was as good as Syn.ConclusionIn conclusion, R+P decreased lipid oxidation (compared to R) and enhanced color stability (compared to R) and offer an alternative to synthetic antioxidants in pre-rigor pork sausage. Furthermore, spiced pork sausage displayed mean redness values above 9 through 245 d, compared to only 75 d in unspiced sausage.

Effect of Organic Acid Applications on Organoleptic Properties of Ground Pork

ObjectivesThe objective of this study was to determine the impact of intervention treatments on the organoleptic properties of ground pork during shelf-life.Materials and MethodsPork trimmings were divided into 22 kg batches for each individual treatment (n = 4 batches). Treatments included control (no intervention), PAA+Titon [Sulfuric acid and sodium sulfate (pH 1.3) combined with peracetic acid (350 ppm)], PAA+Acetic [Peracetic acid (400 ppm) with 2% acetic acid], and LA [Lactic acid (3%)]. After application of each designated treatment, trimmings were ground (coarse and then fine ground) and packaged into 454-g vacuum packaged rollstock packaging. Each package was then stored in dark storage for 0, 7, 14, 21, and 28 d at 2–4°C (n = 8 packages per treatment and time combination). Once each package had reached their designated storage length, packages were removed from storage for sampling. Shelf-life measurements taken included TBARS, raw product odor acceptability, aerobic plate count and psychrotrophic plate count bacterial enumeration. All bacterial enumeration data were converted into log10 for statistical analysis, and the PROC MIXED procedure of SAS was used to determine differences between least squared means (SAS Inst. Inc., Version 9.4, Cary, NC). Odor acceptability was determined using a PROC FREQ.ResultsFor aerobic plate counts (APC), in the ground pork product, a treatment by day interaction occurred (P = 0.007). Psychrotrophic bacterial counts did not differ by treatment or sampling day (P > 0.05). PAA+Titon and LA had decreased lipid oxidation compared to PAA+Acetic and control pork samples over the 28 d of storage. Lipid oxidation didn’t change for all 4 treatments on Days 0, 14, 21, and 28; however, there was an unexplainable spike in lipid oxidation for samples on Day 7. Overall pork odor acceptability differed by storage length (P = 0.02), but not by treatment (P > 0.05). Overall Pork odor acceptability decreased as storage length increased. Acidic off-odor differed by storage length (P = 0.002), but not by treatment (P > 0.05). Acidic off-odor increased as storage length increased. Overall oxidation off-odor did not differ by treatment or aging (P > 0.05). Sweaty off-odor development differed by aging day (P = 0.01) but not by treatment (P > 0.05). Sweaty off-odor reached its highest point within Day 14 and 21 and then decreased. An increasing sour off-odor development differed by ground pork storage length (P = 0.001), but not by treatment (P > 0.05).ConclusionThere were no dramatic negative organoleptic changes to pork trim when treated with selected organic acid interventions prior to grinding, meanwhile there is organoleptic changes by storage length.

Effects of Electrostatic Spray and Natural Antioxidants on Chemical Quality of Grass-Finished Beef Strips Steaks

ObjectivesThis study was aimed to determine how electrostatic spray of natural antioxidants impacts chemical quality of grass-finished beef strip steaks.Materials and MethodsTwenty certified grass-finished beef loins from ten animals were purchased from a certified grass-fed beef purveyor. Two loins of the same animals were cut into sixteen 2.5-cm thick steaks (eight steaks per loin) without the gluteus medius muscle. A factorial arrangement of 4 treatments, including a negative control (no spraying; NEG) and 1000-ppm of electrostatic spray of cherry extract rich in ascorbic acid (ES-ACE), electrostatic spray of rosemary and green tea extract rich in polyphenols (ES-RGT), and pressurized spray of ACE (PS-ACE), and 2 retail time points (0 and 5 d) was randomized within an animal, resulting in two steaks receiving a treatment × day combination within an animal. Five loins were randomly selected for chemical analyses (n = 10 per treatment × day combination). Meat antioxidants were extracted in methanol. The extracted antioxidants were reacted with ABTS+ radical cation (2,2′-azino-bis(3-ethylbenzthiazoline)-6-sulphonic acid diammonium salt) solution diluted to an absorbance of 0.85 to measure Trolox Equivalent Antioxidant Capacity (TEAC) at 734 nm. The extract was also reacted with Folin-Ciocalteu (FC) reagent to measure total phenolic compounds at 765 nm. Thiobarbituric acid reactive substances (TBARS) were extracted in 10% trichloroacetic acid and reacted with thiobarbituric acid and the resulted pigment was measured at 532 nm. Data were analyzed by the GLIMMIX procedure of SAS v9.4 and actual probability was reported.ResultsOn d 0, NEG steaks had less FC values than all treatment steaks (P < 0.001), of which the ES_ACE steaks had 14 and 100% more than PS_ACE and ES_RGT steaks, respectively (P ≤ 0.005). Only ES_ACE steaks had greater FC value than NEG steaks on d 5 (P < 0.001). As a result, TEAC value of ES_ACE steaks was 17 and 75% more than that of PS_ACE and ES_RGT steaks (P ≤ 0.005) and remained greater than that of NEG steaks on d 5 (P = 0.064). Greater antioxidant capacity in ES_ACE and PS_ACE steaks decreased lipid oxidation by 56% (0.9 µg MDA/kg less in ES_ACE and PS_ACE on d 5) as compared with NEG steaks in ES_ACE steaks in contrast to the other treatments (P < 0.001).ConclusionElectrostatic spray of cherry extract rich in ascorbic acid was the most effective antioxidant application to prevent lipid oxidation in grass-finished beef strips steaks.

Effect of Moringa oleifera leaf powder on drying kinetics, physico‐chemical properties, ferric reducing antioxidant power, α‐tocopherol, β‐carotene, and lipid oxidation of dry pork sausages during processing and storage

The potential of Moringa oleifera leaf powder (MLP) to limit lipid oxidation in nitrite‐free unfermented dry pork sausages (droewors) was investigated. Total phenolic compounds, α‐tocopherol and β‐carotene content of MLP was quantified. Droewors with no additives, 0.75 g/100 g MLP or 15 mg/kg vitamin E (VE) oil were processed and sampled after drying (3 days) and during 56 days of storage. Thiobarbituric acid reactive substances (TBARS) of droewors made with MLP were lower until day 10. The effects of 0, 0.5, 1, and 2 g/100 g MLP on TBARS, ferric reducing antioxidant power (FRAP) and the α‐tocopherol, γ‐tocopherol, and β‐carotene content of droewors were assessed during drying and 7 days of storage. MLP inclusion significantly increased FRAP, α‐tocopherol, and β‐carotene content. From the end of drying, TBARS of droewors formulated with MLP were significantly lower compared to droewors formulated without MLP. Increasing the MLP inclusion level had no significant effect on TBARS. Practical applications: The research assesses and demonstrates the potential of Moringa oleifera leaf powder (MLP) as a natural additive to inhibit the rate and extent of lipid oxidation in unfermented dry pork sausages (droewors) with no nitrites/nitrates added. The inclusion of MLP in pork droewors at levels ranging from 0.5 to 2 g/100 g significantly increased the antioxidant activity (FRAP) and quantity of antioxidant vitamins (α‐tocopherol, and β‐carotene) in the product. Higher inhibition of lipid oxidation (TBARS) was observed in droewors with MLP added compared to the positive (vitamin E oil) and negative (no additives) controls. The different MLP inclusion levels used in the study resulted in similar lipid oxidation inhibition. Therefore, the findings show that the application of 0.5 g/100 g MLP is sufficient to decrease lipid oxidation in pork droewors and could potentially be applied to other types of dry‐cured sausages for this purpose.

Anti-Atherosclerotic and Anti-Inflammatory Effects of Curcumin on Hypercholesterolemic Male Rabbits.

Curcumin has a potent antioxidant and anti-inflammatory properties that may suppress inflammatory component of atherosclerosis. It has been demonstrated that curcumin derivatives can reduce the formation of arterial fatty streaks in cholesterol-fed rabbits. Therefore in this study we evaluated the protective effects of Curcumin on the progression of atherosclerosis. 20 mature rabbits were included for this study; they were randomly divided into four groups each of 5. Group 1: (normal control) were fed corn pellets diet and tab water, group 2: (high cholesterol diet control) were kept on cholesterol rich diet (2% cholesterol) and tab water. Group 3: (cholesterol and rosuvastatin treated group) were kept on cholesterol rich diet (2% cholesterol) and 2.5mg/kg/day Rosuvastatin dispersed in DW and given orally, group 4: (cholesterol and curcumin treated group) were kept on cholesterol rich diet (2% cholesterol) and 0.2% curcumin added with corn pellets. The study continued for 12weeks then assessment of serum level of high sensitive C-reactive protein, ICAM1, VCAM1 and PCSK9 was carried out at the end of the study. Total antioxidant activity of curcumin was also determined. Histopathological examination of aortic tissues for atherosclerotic changes was also carried out. Atherogenic (cholesterol rich diet) induced an increment in serum level of TC, LDL, VLDL and TG with concomitant decrement in serum level of HDL and increased atherogenic index. Treatment with curcumin produced substantial reduction in serum TC, LDL, TG with no effect on HDL level thus decreased atherogenic index. Rabbits treated with curcumin showed a significant reduction in the serum level of high sensitive C-reactive protein, ICAM1, VCAM, PCSK9 serum expression and aortic total antioxidant capacity. Curcumin has a potent anti-inflammatory and anti- oxidant effects against atherosclerosis so exerts a protective role by decreasing lipid oxidation and inflammatory markers.

Gene Expression and Fatty Acid Profiling in Longissimus thoracis Muscle, Subcutaneous Fat, and Liver of Light Lambs in Response to Concentrate or Alfalfa Grazing.

A better understanding of gene expression and metabolic pathways in response to a feeding system is critical for identifying key physiological processes and genes associated with polyunsaturated fatty acid (PUFA) content in lamb meat. The main objective of this study was to investigate transcriptional changes in L. thoracis (LT) muscle, liver, and subcutaneous fat (SF) of lambs that grazed alfalfa (ALF) and concentrate-fed (CON) slaughtered at 23 kg and using the Affymetrix Ovine Gene 1.1 ST whole-genome array. The study also evaluated the relationship between meat traits in LT muscle, including color, pigments and lipid oxidation during 7 days of display, α-tocopherol content, intramuscular fat (IMF) content and the fatty acid (FA) profile. Lambs that grazed on alfalfa had a greater α-tocopherol concentration in plasma than CON lambs (P < 0.05). The treatment did not affect the IMF content, meat color or pigments (P > 0.05). Grazing increased the α-tocopherol content (P < 0.001) and decreased lipid oxidation on day 7 of display (P < 0.05) in LT muscle. The ALF group contained a greater amount of conjugated linoleic acid (CLA), C18:3 n−3, C20:5 n−3, C22:5 n−3, and C22:6 n−3 than did the CON group (P < 0.05). We identified 41, 96 and four genes differentially expressed in LT muscle, liver, and subcutaneous fat, respectively. The most enriched biological processes in LT muscle were skeletal muscle tissue development, being the genes related to catabolic and lipid processes downregulated, except for CPT1B, which was upregulated in the ALF lambs. Animals grazing alfalfa had lower expression of desaturase enzymes in the liver (FADS1 and FADS2), which regulate unsaturation of fatty acids and are directly involved in the metabolism of n−3 PUFA series. The results found in the current study showed that ingesting diets richer in n−3 PUFA might have negative effects on the de novo synthesis of n−3 PUFA by downregulating the FADS1 and FADS2 expression. However, feeding diets poorer in n−3 PUFA can promote fatty acid desaturation, which makes these two genes attractive candidates for altering the content of PUFAs in meat.

Review on Natural Preservatives for Extending Fish Shelf Life.

Fish is extremely perishable as a result of rapid microbial growth naturally present in fish or from contamination. Synthetic preservatives are widely used in fish storage to extend shelf life and maintain quality and safety. However, consumer preferences for natural preservatives and concerns about the safety of synthetic preservatives have prompted the food industry to search natural preservatives. Natural preservatives from microorganisms, plants, and animals have been shown potential in replacing the chemical antimicrobials. Bacteriocins and organic acids from bacteria showed good antimicrobial activities against spoilage bacteria. Plant-derived antimicrobials could prolong fish shelf life and decrease lipid oxidation. Animal-derived antimicrobials also have good antimicrobial activities; however, their allergen risk should be paid attention. Moreover, some algae and mushroom species can also provide a potential source of new natural preservatives. Obviously, the natural preservatives could perform better in fish storage by combining with other hurdles such as non-thermal sterilization processing, modified atmosphere packaging, edible films and coatings.

Evaluation of physicochemical properties and volatile compounds of Chinese dried pork loin curing with plasma-treated water brine

The application of dielectric barrier discharge cold plasma (DBD-CP)-treated water as a novel curing process for manufacturing Chinese dried pork loin was investigated. The treatment time of DBD-CP was optimized based on the pH and nitrite level of the plasma-treated water (PTW). PTW treated for 3 min had an alkaline environment and a higher nitrite content than that at the other lengths of treatment time. Pork loins were marinated in control or PTW brine at 4 °C for 24 h and then dry-ripened for 15 days. PTW with a higher treatment voltage significantly decreased lipid oxidation of the products and led to an increased a* value (redness) and an increased residual nitrite content in products that was still within the range of use (all P < 0.05). The contents of each free amino acid increased with increasing treatment intensity (P < 0.05). There were 22 new volatile compounds generated in PTW-cured products, such as 3-methyl-butanol, hexanal and 2,3-octanedione, while six substances were lost, such as 2-pentylfuran, compared with those in the control. This study indicates that using PTW as a curing method can be a potential and effective way of producing dried pork meat products.

Antioxidant Effect of Extracts from Native Chilean Plants on the Lipoperoxidation and Protein Oxidation of Bovine Muscle.

The present study investigated the antioxidant potential and the ability to inhibit lipid and protein oxidation in bovine meat of four native Chilean species: canelo (Drimys winteri), nalca (Gunnera tinctoria), tiaca (Caldcluvia paniculata), and ulmo (Eucryphia cordifolia). Phenolic acids (gallic, chlorogenic, caffeic, and coumaric) and flavonoids (catechin, epicatechin, and rutin) were identified and quantified by HPLC-MS/MS. Drimys winteri extract exhibited the highest antioxidant capacity evaluated by oxygen radical absorption capacity-red pyrogallol method (ORAC-PGR) and ferric ion reducing antioxidant power (FRAP) assays. All extracts decreased lipid oxidation induced by 2,2’-azo-bis(2-amidinopropane) dihydrochloride (AAPH) derived peroxyl radicals by anywhere between 30% and 50% the. In addition, canelo and nalca extracts decreased spontaneous oxidation by around 57% and 37% in relation to the control group, being even more efficient than butylated hydroxyanisole (BHT) a synthetic antioxidant. Protein oxidation in the myofibrillar proteins was evaluated by the formation of protein carbonyls and loss of protein thiols. The canelo, ulmo, and nalca extracts decreased the formation of carbonyls by around 30%. Plant extracts and BHT did not show an antioxidant effect on protein thiol loss. However, tiaca and ulmo extracts exerted a pro-oxidant effect, favoring the oxidation of sulfhydryl groups. The oxidizing system induced structural changes in myofibrillar protein (SDS−PAGE). A protective effect on protein structure from the canelo extract can be observed during the incubation when compared to samples incubated with AAPH.

Temperature‐sensitive polyurethane (TSPU) film incorporated with carvacrol and cinnamyl aldehyde: antimicrobial activity, sustained release kinetics and potential use as food packaging for Cantonese‐style moon cake

SummaryTemperature‐sensitive polyurethane (TSPU) films incorporated with carvacrol and cinnamyl aldehyde were prepared for the potential use of food packaging. The antimicrobial properties and sustained release kinetics of carvacrol and cinnamyl aldehyde in TSPU film were investigated. Results indicated that cinnamyl aldehyde and carvacrol had favourable antimicrobial properties at relatively low addition ratio. The diffusion and release of carvacrol were linearly related to temperature and its addition ratio. The release rates of carvacrol from TSPU film increased from 0.6% to 2.2% with the increase of addition ratio and temperature. The first‐order kinetic equation could be used to describe its diffusion and sustained release process. TSPU films could significantly prolong the shelf life of Cantonese‐style moon cakes by effectively inhibiting microbial growth and decreasing lipid oxidation comparing with commonly used polyethylene food packaging. Results obtained in the present work can provide technical guide of sustained release food packaging films with antimicrobial properties.

Effects of Caesalpinia sappan L. extract on the color stability, antioxidant and antimicrobial activity in cooked pork sausages during cold storage

The effects of C. sappan L. extract on oxidative stability, microbiological quality, and color attributes in sausages were examined. Pork sausages were prepared for four treated groups: control (without antioxidant), T1 (added with 0.007% sodium nitrite), T2 (added with 0.1% C. sappan L.), and T3 (added with 0.0035% sodium nitrite+0.1% C. sappan L.). T3 showed lower L. monocytogenes count than that saw in the control and T2 (p < 0.05). T2 had lower E. coli counts than those of T1 (p < 0.05). Inclusion of the 0.1% C. sappan L. in sausages resulted in lower lightness and higher redness compared with control (p < 0.05). T3 had the highest DPPH free radical scavenging ability followed by T2 (p < 0.05). T2 decreased lipid oxidation and had values similar to those of T1 (p < 0.05). Moreover, T2 had the highest thiol content with sausages at 2 and 4 weeks (p < 0.05). In conclusion, 0.1% C. sappan L. extracts exhibited the effectiveness in antioxidant performance, antimicrobial qualities, and color consistency in cooked pork sausages during storage.

The RNA binding protein HuR influences skeletal muscle metabolic flexibility in rodents and humans

BackgroundMetabolic flexibility can be assessed by changes in respiratory exchange ratio (RER) following feeding. Though metabolic flexibility (difference in RER between fasted and fed state) is often impaired in individuals with obesity or type 2 diabetes, the cellular processes contributing to this impairment are unclear. Materials and methodsFrom several clinical studies we identified the 16 most and 14 least metabolically flexible male and female subjects out of >100 participants based on differences between 24-hour and sleep RER measured in a whole-room indirect calorimeter. Global skeletal muscle gene expression profiles revealed that, in metabolically flexible subjects, transcripts regulated by the RNA binding protein, HuR, are enriched. We generated and characterized mice with a skeletal muscle-specific knockout of the HuR encoding gene, Elavl1 (HuRm−/−). ResultsMale, but not female, HuRm−/− mice exhibit metabolic inflexibility, with mild obesity, impaired glucose tolerance, impaired fat oxidation and decreased in vitro palmitate oxidation compared to HuRfl/fl littermates. Expression levels of genes involved in mitochondrial fatty acid oxidation and oxidative phosphorylation are decreased in both mouse and human muscle when HuR is inhibited. ConclusionsHuR inhibition results in impaired metabolic flexibility and decreased lipid oxidation, suggesting a role for HuR as an important regulator of skeletal muscle metabolism.

Textural properties, sensory acceptance and fatty acid profile of cooked meat batters employing pumpkin seed paste or soybean oil oleogel as fat replacers

Oleogel from soybean oil and pumpkin seed paste were proposed as full replacements for pork backfat to decrease the saturated fat contents and improve the PUFA/SFA ratio in meat batters. Textural compression, along with shear and penetration tests provided similar information related to meat batter structure according to the type of fat, showing that a tougher but brittle texture was produced. Meat batters with fat replacers were darker and less red, but more yellow due to the incorporation of vegetable oil. Both hue angle (H) and saturation index (S) values increased due to changes in color components, in addition to a higher total color difference compared to the control sample. Soybean oil oleogel increased the PUFA content considerably, maintaining a total fat content close to the control sample. Pumpkin seed paste increased PUFA but also reduced to caloric content due lower fat content. Consumers preferred pumpkin seed paste samples regardless of the color difference and lower fat content. Fat replacers employed to replace pork backfat substantially modified the fatty acid profile and decreased lipid oxidation with no detrimental effects on texture or acceptance.

A comparative study of anti-atherosclerotic/anti-inflammatory effect of irbesartan and rosuvastatin in hypercholesterolemic male rabbits

Objective: To evaluate the potential protective effect of irbesartan on atherosclerotic progression using rosuvastatin as a positive control.&#x0D; Methods: Twenty local domestic rabbits were randomly divided into four groups, five rabbits per each group. The first group (I), rabbits were receiving normal diet; the second group (II), rabbits were receiving 2 % cholesterol diet; the third group (III), rabbits were receiving rosuvastatin and 2% cholesterol diet and; the fourth group (IV), rabbit were receiving irbesartan and 2% cholesterol diet. Serum level of cholesterol, triglycerides, LDL, VLDL and HDL were determined after 12 weeks of the study. Serum level of high sensitive C-reactive protein, ICAM1and VCAM1 were measured after 12 weeks of the study. Total antioxidant activity was also determined. Aortic tissue sent for histopathological examination of atherosclerosis lesion.&#x0D; Result: Data of this study have showed that atherogenic diet caused an increase in serum level of TC, LDL, VLDL and TG and a decrease in serum level of HDL. Treatment of rabbits with irbesartan caused substantial decrease in serum lipid profile compared with untreated rabbit receiving atherogenic diet. No significant difference was seen between irbesartan- and rosuvastatin-treated rabbits in all lipid parameters measured with the exception that the HDL level in rosuvastatin-treated rabbits was significantly higher than that of irbesartan-treated rabbits. Rabbit treated with irbesartan showed a significant decrease in the serum level of high sensitive C-reactive protein, ICAM1, VCAM1 and aortic total antioxidant capacity when compared with untreated group. No significant difference was seen between irbesartan- and rosuvastatin-treated rabbits in all these inflammatory parameters measured. Histopathological examination showed that irbesartan decreased atherogenic lesion significantly when compared with untreated rabbits.&#x0D; Conclusion: Irbesartan has a potential protective effect against atherosclerosis via decreasing lipid oxidation and inflammatory mediators. In terms of lipid lowering and anti-inflammatory effects, irebsartan has similar pattern of effectiveness to rosuvastatin.

Oxidative Stability, Affective and Descriptive Sensory Properties of Roasted Peanut Flavored with Oregano, Laurel, and Rosemary Essential Oils as Natural Preservatives of Food Lipids

The objective of the study is to evaluate lipid oxidation stability in roasted peanuts with essential oils as natural antioxidants. Laurel, oregano, and rosemary essential oil (LEO, OEO, and REO, respectively) provide preliminary antioxidant activity determined by free radical scavenging activity (DPPH test) of 61.1, 58.4, and 47.9% and total phenolic content of 10.3, 10.6, and 8.4 mg g−1 for LEO, OEO, and REO, respectively. Essential oil (EO; 0.02% p/p) is added to roasted peanuts and an affective sensory test (nine‐point hedonic scale) shows that samples with OEO have greater values (6.74) than those of other samples (≈6.20). Chemical (peroxide anisidine diene content and Totox values) volatile (hexanal and 2‐heptenal) and sensory (oxidized and cardboard intensity) indicators change over 84 storage days. Samples with EOs show lower values than those for controls decreasing lipid oxidation. Samples with BHT have the lowest values for deterioration indicators. Principal component analysis of EOs for all indicators and samples with EOs shows that LEO and OEO have better antioxidant properties than REO. Coefficient regression between sensory variables peroxide value and hexanal has a good correlation and can be used as a predictor equation. Essential oils can be used as flavor and natural antioxidant agent in roasted peanut.Practical Applications: The authors believe in the importance of replacing the use of synthetic antioxidants with natural antioxidants in foods. Synthetic antioxidants are being questioned by the perception of safety that these offer by consumers. The essential oils present an antioxidant alternative since their components possess these properties and the application of them is a reason for research to be able to provide more information to the food industry. The sensory properties of essential oils are well received by consumers and the potential for their application as functional flavorings is in its initial stages. That is why this research collaborates with the use of the essential oils of oregano, laurel, and rosemary as possible antioxidants and flavors in peanuts roasted or in other food (which is susceptible to oxidative processes) evidenced its antioxidant properties and the modification of taste and sensory perception by the consumers.Oregano, laurel, and rosemary essential oils can be used as antioxidants in peanut products and foods with high lipid content.

Innate immune regulatory networks in hepatic lipid metabolism.

Hepatic lipid metabolism is closely associated with certain diseases, such as obesity, diabetes, fatty liver, and hepatic fibrosis. Hepatic steatosis results from systemic metabolic dysfunction that occurs via multiple processes. The initial process has been characterized as hepatic lipid accumulation that may be caused by increased liver lipid uptake and de novo lipogenesis or decreased lipid oxidation and lipid export; subsequently, multiple additional factors that trigger inflammation and insulin resistance (IR) aggravate the progression of hepatic steatosis. Emerging evidence indicates that inflammation stands at the crossroads of innate immunity and lipid metabolism and links the initial metabolic stress and subsequent metabolic events in lipid metabolism. Therefore, in this review, we summarize the regulatory role of innate immune signaling molecules in maintaining lipid metabolic homeostasis; these revelations can guide the development of potential therapies for nonalcoholic fatty liver disease (NAFLD).

High Pancreatic Amylase Expression Promotes Adiposity in Obesity-Prone Carbohydrate-Sensitive Rats

We have reported large differences in adiposity (fat mass/body weight) gain between rats fed a low-fat, high-starch diet, leading to their classification into carbohydrate "sensitive" and "resistant" rats. In sensitive animals, fat accumulates in visceral adipose tissues, leading to the suggestion that this form of obesity could be responsible for rapid development of metabolic syndrome. We investigated whether increased amylase secretion by the pancreas and accelerated starch degradation in the intestine could be responsible for this phenotype. Thirty-two male Wistar rats (7-wk-old) were fed a purified low-fat (10%), high-carbohydrate diet for 6 wk, in which most of the carbohydrate (64% by energy) was provided as corn starch. Meal tolerance tests of the Starch diet were performed to measure glucose and insulin responses to meal ingestion. Indirect calorimetry combined with use of 13C-labelled dietary starch was used to assess meal-induced changes in whole body and starch-derived glucose oxidation. Real-time polymerase chain reaction was used to assess mRNA expression in pancreas, liver, white and brown adipose tissues, and intestine. Amylase activity was measured in the duodenum, jejunum, and ileum contents. ANOVA and regression analyses were used for statistical comparisons. "Resistant" and "sensitive" rats were separated according to adiposity gain during the study (1.73%±0.20% compared with 4.35%±0.36%). Breath recovery of 13CO2 from 13C-labelled dietary starch was higher in "sensitive" rats, indicating a larger increase in whole body glucose oxidation and, conversely, a larger decrease in lipid oxidation. Amylase mRNA expression in pancreas, and amylase activity in jejunum, were also higher in sensitive rats. Differences in digestion of starch can promote visceral fat accumulation in rats when fed a low-fat, high-starch diet. This mechanism may have important implications in human obesity.

Lipid Oxidation and Color Stability of Spiced and Unspiced Pork Sausage with a Novel Antioxidant Mixture of Rosemary Extract and Phospholipase A2

ObjectivesThe objective of this study was to measure the loss of redness and onset of lipid oxidation in pre-rigor pork sausage containing synthetic antioxidants (Syn) compared to rosemary extract (R), and a combination of R with different concentrations of phospholipase A2 (R+P) over both light display and frozen storage.Materials and MethodsOur work examined pre-rigor spiced and unspiced pork sausage. Tissue from sows for both spiced and unspiced sausage was coarse ground and cooled to 1–3°C with dry ice within 1-h post-exsanguination. Water, treatments and seasonings were added, and the sausage stuffed within 2 h post-exsanguination for spiced sausages. Water and treatments were added 24 h post-exsanguination for the unspiced sausage. Sausages were stored in the dark at –20°C (to 110 and 245 d for unspiced and spiced, respectively) prior to light display. Sausages were sampled for color and lipid oxidation on approximately 40-d intervals of –20°C dark storage and 7–9 d of light display (5°C). In spiced sausage, R (type HT-P) was added at 200 ppm, PLA2 was added at 0.4 ppm. Butylated hydroxyanisole (BHA), propyl gallate (PG) and citric acid (CA) were each added at 0.01% of the estimated fat and collectively formed the Syn treatment. Spices consisted of sucrose, ginger, coriander, nutmeg, white pepper, and MSG. In unspiced sausage R was added at 200 ppm, PLA2 added at 0.4 ppm and 10 ppm, and BHA, CA and PG added at the same levels as in spiced sausage. Color stability was measured based on redness (a*). Peroxide values (PVs) were measured spectrophotometrically, headspace hexanal was measured via gas chromatography (GC) and α tocopherol depletion was measured with HPLC fluorescence detection as markers of lipid oxidation. Total lipids were fractionated to gravimetrically quantify neutral lipids, free fatty acids and polar lipids and to measure PVs in the aforesaid fractions. Unspiced sausages were only stored for 110 d because of rampant lipid oxidation and loss of color.ResultsIn spiced sausage, R and R+P displayed better color stability than both the control (no antioxidant, C) and Syn. Syn displayed the lowest hexanal values. R had the highest PVs and both Syn and R+P were significantly lower. Free fatty acids were the most heavily oxidized fraction on an oil basis, while neutral lipids were the most oxidized lipid on a wet weight basis. Alpha tocopherol did not deplete through 245 d in spiced sausage but was not detected in the unspiced sausage.In unspiced sausage, R+P was examined at two different levels (0.4 ppm and 10 ppm PLA2). R+P (10 ppm) exhibited lower headspace hexanal than R alone and R+P at both levels performed as well as Syn. In addition, R+P at both levels displayed significantly better color stability than R alone and was as good as Syn.ConclusionIn conclusion, R+P decreased lipid oxidation (compared to R) and enhanced color stability (compared to R) and offer an alternative to synthetic antioxidants in pre-rigor pork sausage. Furthermore, spiced pork sausage displayed mean redness values above 9 through 245 d, compared to only 75 d in unspiced sausage.

Effect of Organic Acid Applications on Organoleptic Properties of Ground Pork

ObjectivesThe objective of this study was to determine the impact of intervention treatments on the organoleptic properties of ground pork during shelf-life.Materials and MethodsPork trimmings were divided into 22 kg batches for each individual treatment (n = 4 batches). Treatments included control (no intervention), PAA+Titon [Sulfuric acid and sodium sulfate (pH 1.3) combined with peracetic acid (350 ppm)], PAA+Acetic [Peracetic acid (400 ppm) with 2% acetic acid], and LA [Lactic acid (3%)]. After application of each designated treatment, trimmings were ground (coarse and then fine ground) and packaged into 454-g vacuum packaged rollstock packaging. Each package was then stored in dark storage for 0, 7, 14, 21, and 28 d at 2–4°C (n = 8 packages per treatment and time combination). Once each package had reached their designated storage length, packages were removed from storage for sampling. Shelf-life measurements taken included TBARS, raw product odor acceptability, aerobic plate count and psychrotrophic plate count bacterial enumeration. All bacterial enumeration data were converted into log10 for statistical analysis, and the PROC MIXED procedure of SAS was used to determine differences between least squared means (SAS Inst. Inc., Version 9.4, Cary, NC). Odor acceptability was determined using a PROC FREQ.ResultsFor aerobic plate counts (APC), in the ground pork product, a treatment by day interaction occurred (P = 0.007). Psychrotrophic bacterial counts did not differ by treatment or sampling day (P > 0.05). PAA+Titon and LA had decreased lipid oxidation compared to PAA+Acetic and control pork samples over the 28 d of storage. Lipid oxidation didn’t change for all 4 treatments on Days 0, 14, 21, and 28; however, there was an unexplainable spike in lipid oxidation for samples on Day 7. Overall pork odor acceptability differed by storage length (P = 0.02), but not by treatment (P > 0.05). Overall Pork odor acceptability decreased as storage length increased. Acidic off-odor differed by storage length (P = 0.002), but not by treatment (P > 0.05). Acidic off-odor increased as storage length increased. Overall oxidation off-odor did not differ by treatment or aging (P > 0.05). Sweaty off-odor development differed by aging day (P = 0.01) but not by treatment (P > 0.05). Sweaty off-odor reached its highest point within Day 14 and 21 and then decreased. An increasing sour off-odor development differed by ground pork storage length (P = 0.001), but not by treatment (P > 0.05).ConclusionThere were no dramatic negative organoleptic changes to pork trim when treated with selected organic acid interventions prior to grinding, meanwhile there is organoleptic changes by storage length.