Oxidative stability of brined anchovies (Engraulis encrasicholus) with plant extracts

The effect of brining with plant extracts on the oxidative stability of anchovies was investigated during storage. The brining process was done in 15 g 100 mL⁻¹ of sodium chloride solution with water, and with myrtle, rosemary and nettle extracts. Brined anchovies were stored at 4 ± 1  ° C for 28 days. Brining with plant extracts slowed down the lipid oxidation of anchovies. The highest antioxidant effect was observed in brined anchovies with rosemary and myrtle extracts during storage as indicated by peroxide value (POV), thiobarbituric acid reactive substance and oxidative rancidity (OR) scores. Furthermore, OR scores in brined anchovies were well correlated with thiobarbituric acid reactive substance ( r ² = 0.66, P  < 0.01) and POV ( r ² = 0.87; P  < 0.01). The fatty acid profiles were similar among the brined anchovies with plant extracts. These results suggest that brining with rosemary, myrtle and to a lesser extent, nettle extracts prevents development of oxidation in lipids of anchovies during storage.     

Comparative addition of rosemary extract and additives on sensory and antioxidant properties of retail packaged beef

The antioxidant capacity of an organoleptically mild, water‐ and oil‐soluble rosemary extract (RE) was compared with tert‐butyl‐4‐hydroxyanisol (BHA)/tert‐butyl‐4‐hydroxytoluene (BHT) and vitamin E (through dietary supplementation). An optimum concentration of RE (0.1%) was established from sensory trials and used for subsequent analyses. Beef burgers containing added antioxidants were held under simulated retail conditions and monitored for lipid (TBARS) and colour (Hunter ‘a’) stability. RE was more effective in controlling lipid oxidation in aerobically stored samples compared with control or BHA/BHT samples. Similar findings were observed for burgers stored under modified atmosphere although RE was also more effective than vitamin E under these conditions. Addition of RE to vitamin E supplemented beef resulted in lowest TBARS values and suggests a synergistic effect between RE and vitamin E. RE did not improve meat redness compared with other treatments. Water and oil (O/W) soluble RE offers considerable potential as a natural antioxidant for food products.     

Rosemary powder filtrate improves the oxidative stability and antioxidant properties of rapeseed oil: potential applications for domestic cooking

Rapeseed oil is an important source of edible oil for the human diet but is also highly susceptible to oxidative deterioration. Previous research has demonstrated that rosemary powder and its extracts can increase the oxidative stability of rapeseed oil. In this study, the protective effect of ground rosemary powder (0.25–2.0%) against the oxidative degradation of filtered rapeseed oil was assessed. Rapeseed oil filtrate showed enhanced antioxidant capacity and higher induction periods (IP) based on Rancimat analysis. Lower conductivity changes and total colour differences, reduced malondialdehyde and conjugated dienes content, and higher levels of tocopherols and carotenoids were observed for the oils formulated with rosemary powder after 1.5 and 3 h of exposure to accelerated oxidation. The use of rosemary powder filtrate could be an effective way to protect rapeseed oil from oxidation during storage or cooking with domestic and commercial applications.     

Inhibition of Heterocyclic Amine Formation in Beef Patties by Ethanolic Extracts of Rosemary

ABSTRACT: Heterocyclic amines (HCAs) are mutagenic compounds formed during cooking muscle foods at high temperature. Inhibition of HCAs by rosemary extracts were evaluated with beef patties cooked at 191 °C (375 °F) for 6 min each side and 204 °C (400 °F) for 5 min each side. Five rosemary extracts extracted with different solvents were used in this study: extract 100W (100% water), 10E (10% ethanol), 20E (20% ethanol), 30E (30% ethanol), and 40E (40% ethanol). The 5 extracts were directly added to beef patties at 3 levels (0.05%, 0.2%, and 0.5%) before cooking and HCA contents were extracted and quantified. All of the patties contained 2-amino-3,8-dimethylimidazo [4,5-f]quinoxaline (MeIQx), and 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP). There was no statistical difference in the inhibition of HCAs in the 0.05%, 0.2%, and 0.5% rosemary extracts. All rosemary extracts significantly decreased the levels of MeIQx and PhIP at both cooking conditions. When cooking at 204 °C (400 °F) for 5 min each side, rosemary extracts 10E and 20E were superior to rosemary extracts 100W, 30E, and 40E in inhibiting HCA formation. Rosemary extract 20E showed the greatest inhibition of MeIQx (up to 91.7%) and PhIP (up to 85.3%). The inhibiting effect of rosemary extracts on HCA formation corresponded to their antioxidant activity based on a DPPH scavenging assay. Rosemary extract 10E and 20E contain a mixture of rosmarinic acid, carnosol, and carnosic acid. It is possible that these compounds might act synergistically in inhibiting the formation of HCAs.     

Optimization of physicochemical changes of palm olein with phytochemical antioxidants during deep-fat frying

Response surface methodology (RSM) was used to optimize the amounts of rosemary and sage extracts together with citric acid as synergist antioxidants in stabilizing refined, bleached, and deodorized palm olein during repeated deep-fat frying of potato chips. For all physicochemical properties studied, these phytochemical antioxidant treatments significantly (P<0.05) reduced the oxidation rate of the oil. During 5 d of frying, anisidine value, peroxide value, free fatty acid, polymer content, color units, viscosity, and absorbances at 232 and 268 nm gradually increased, whereas iodine value and ratio of 18∶2/16∶0 decreased. Further statistical analyses, including coefficient of determination (R ²) and probability of F values, indicated that mathematical models for each physicochemical parameter could be developed confidently in this study, with R ² for all parameters greater than 0.90. These results suggested that an optimal mixture of phytochemical antioxidants derived from rosemary and sage together with citric acid could be produced using RSM for stabilizing thermally processed oil. For many physicochemical parameters examined, the use of moderate levels of antioxidants could result in optimal responses.     

Whey protein active films incorporated with a blend of essential oils: Characterization and effectiveness

Whey protein concentrate (WPC) films incorporated with a blend of Cinnamomum cassia, Cinnamomum zeylanicum, and Rosmarinus officinalis essential oils were characterized and evaluated for their effectiveness as an antioxidant for food applications. The effect of the incorporation of essential oils (EOs) at different concentrations (1, 2, 2.7, and 5% w/w) in WPC were studied by measuring their physical, optical, mechanical, and microstructural properties, in order to evaluate their behavior as a food packaging. The effectiveness of these active WPC films as a packaged was evaluated using a fatty food model (salami). The state of the salami oxidation was measured by the TBARs and hexanal assays during 180 days of storage. A yellowish characteristic color and opacity of WPC‐based films tend to increase with the increase of the EO concentration in the film formulation. While films containing 1 and 2% of EOs showed to be the most hydrophobic and present the lowest moisture content and solubility in water, films with higher EOs % (2, 2.7, and 5%, w/w) presented the highest water vapor transmission rate. The developed WPC active films showed to be heterogeneous, presenting cracks and pores due to the weakening of the polymer chain interaction forces by the EOs, which affected their mechanical behavior. WPC films incorporated with EOs may retard lipid oxidation induced by UV light in food. Besides, they showed to be very effective in the reduction of lipid oxidation in a previous assay with salami, with a longer storage time.     

Effect of long‐term dietary administration of oregano and rosemary on the antioxidant status of rat serum,liver, kidney and heart after carbon tetrachloride‐induced oxidative stress

BACKGROUND: This study was performed on female Wistar rats allocated to eight groups of six animals each. Groups 1 and 2 were fed the basal diet, groups 3 and 4 were fed the basal diet supplemented with ground oregano at 20 g kg^?1 level, groups 5 and 6 were fed the basal diet supplemented with ground rosemary at 20 g kg^?1 level, while groups 7 and 8 were fed the basal diet supplemented with both oregano and rosemary, each at 20 g kg^?1 level. Following 6 weeks feeding, groups 2, 4, 6 and 8 were injected with CCl₄ at 1 mL kg^?1 body weight, and 6 h thereafter all animals were sacrificed. RESULTS: Administration of CCl₄ to the control rats enhanced (P < 0.05) aspartate transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase (ALP) activities, decreased cholesterol and triglycerides content in serum, increased (P < 0.05) lipid peroxidation and decreased (P < 0.05) the ABTS radical cation, the hydroxyl anion radical, the superoxide anion radical, and the hydrogen peroxide scavenging activities in all tested tissues, as compared to the control. Feeding oregano, rosemary or both before CCl₄ treatment resulted in decline (P < 0.05) of the increase in AST, ALT and ALP activities, increase (P < 0.05) of cholesterol and triglycerides in serum, decrease (P < 0.05) of lipid peroxidation, and increase (P < 0.05) of the ABTS radical cation, hydroxyl anion radical, superoxide anion radical and hydrogen peroxide scavenging activity. CONCLUSION: The results of this study suggest that long‐term dietary administration of oregano and rosemary has the potential to quench free radicals and alleviate CCl₄‐induced oxidative stress in rats. Copyright © 2009 Society of Chemical Industry     

Determination of the Most Bioactive Phenolic Compounds from Rosemary Against Listeria Monocytogenes: Influence of Concentration, pH, and NaCl

ABSTRACT: The anti-Listeria monocytogenes effects of 8 phenolic compounds, carnosol, carnosic acid, 12-methoxy carnosic, ferulic and caffeic acid, rosmarinic acid, luteolin and luteolin-7-glucoside were evaluated with a Plackett and Burman design in mixtures mimicking the phenolic composition of rosemary extract without essential oils. At 30°C carnosic acid was the most efficient compound during 24 h, whereas luteolin became more active after 72 h. The antibacterial effect of pure carnosic acid was modeled under a range of different pH and NaCl concentration, using a Doehlert design. Under moderately acidified conditions, carnosic acid displayed a bactericidal effect at low concentration (5.5 μg/ml). Its activity was not greatly influenced by NaCl.     

Synergistic effects of rosemary, sage, and citric acid on fatty acid retention of palm olein during deep-fat frying

A study to optimize the use of oleoresin rosemary extract, sage extract, and citric acid in refined, bleached, and deodorized (RBD) palm olein during deep-fat frying of potato chips was performed using response surface methodology. Results showed that the natural antioxidants used in this study retarded oil deterioration, as evidenced by retention of fatty acid profiles. The linoleic to palmitic (C18∶2/C16∶0) ratio was chosen as the parameter for optimizing the use of natural antioxidants in RBD palm olein during deep-fat frying. Linoleic (R ²=0.946) and palmitic (R ²=0.825) acids were found to be the most important dependent variables, giving highest R ² values to various antioxidant treatments after 25 h of frying. All three antioxidants had independent significant (P<0.05) effects on the C18∶2/C16∶0 ratio. In fact, significant effects on the C18∶2/C16∶0 ratio of RBD palm olein were also given by a second-order form. A combination of 0.076% oleoresin rosemary extract, 0.066% sage extract, and 0.037% citric acid produced the optimal retention of the essential fatty acid C18∶2. In addition, a synergistic effect among these antioxidants on the fatty acid ratio of RBD palm olein was found.     

迷迭香添加鱼肉蛋白可食膜的制备与特性

以鲢鱼肉为主要原料制备蛋白可食膜,测定了迷迭香抗氧化剂添加对膜理化性质和抗氧化性能的影响。结果表明,利用鲢鱼肉可以制备成无色透明的蛋白可食膜,鱼肉蛋白膜的机械性质和水蒸气透过性（WVP）主要由肌原纤维蛋白含量决定,在鱼种间的差异并不显著。添加迷迭香抗氧化剂对鱼肉蛋白膜的机械性质和WVP影响不显著,但对膜的阻隔紫外线能力和抗氧化性能有提高作用。将蛋白膜包装的鳗鱼肉在37℃下放置12h,与未包装样品相比,鳗鱼肉的POV和TBARS的增加明显得到抑制,而添加迷迭香会进一步提高其抑制效果。