The antioxidative properties of Holy basil and Galangal in cooked ground pork

The ethanolic extracts from Holy basil and Galangal were examined for their extraction yield, total phenolic content, antioxidant activity against a β-carotene-linoleic acid emulsion system, DPPH scavenging activity and reducing power. Ethanolic extracts of Holy basil exhibited higher extraction yield, total phenolic content, antioxidant activity, DPPH scavenging activity and reducing power than ethanolic extracts of Galangal. Antioxidative efficiency to inhibit lipid oxidation of dried Holy basil and dried Galangal powder, ethanolic extracts of Galangal and Holy basil and commercial antioxidant mixture in cooked ground pork was investigated during refrigerated storage at 5°C for 14 days. The quantitative measurements of thiobarbituric acid reactive substances (TBARS), conjugated diene, peroxide value (POV) and hexanal content were used as indicators of lipid oxidation. Increased levels of TBARS value, POV and hexanal content were noticed in all meat samples during storage, however most marked in cooked ground pork without antioxidants, whereas conjugated diene tended to decrease with increasing storage time. Ranking of the treatment in order of their antioxidant effectiveness showed that commercial antioxidant mixture (0.3% citric acid+0.5% ascorbic acid+0.02% α-tocopherol)>dried Galangal powder>dried Holy basil powder>ethanolic extracts of Galangal>ethanolic extracts of Holy basil>control. Furthermore, in cooked ground pork samples a high correlation between TBARS value and hexanal contents was obtained.     

Effect of Cooking Method and Ethanolic Tocopherol on Oxidative Stability and Quality of Beef Patties During Refrigerated Storage (Oxidative Stability of Cooked Patties)

ABSTRACT: Incorporation of δ-tocopherol using an ethanolic carrier to control lipid oxidation in impingement and ohmic cooked beef patties was evaluated, and quality characteristics were determined. Ethanolic δ-tocopherol delayed oxidative deterioration of cooked beef patties in both cooking methods. Ohmic cooked samples developed significantly higher ( P < 0.05) thiobarbituric acid-reactive substances (TBARS) than impingement-cooked samples. Formation of TBARS significantly ( P < 0.05) increased with storage time in both cooking treatments. Cooking method significantly ( P < 0.05) influenced color and textural attributes of beef patties. Samples cooked by ohmic heater were lighter, displaying significantly ( P < 0.05) larger L * color values. Additionally, ohmic samples were harder, chewier, and more cohesive ( P < 0.05) than samples cooked with an impingement oven. Exogenous addition of ethanolic tocopherol can delay lipid oxidation and improve quality of cooked meat products.     

Effect of plant phenolics,tocopherol and ascorbic acid on oxidative stability of pork patties

BACKGROUND: There is great interest in the use of naturally occurring antioxidants to delay oxidation in meat products. The effect of rosemary extract (RE), green tea extract (TE), tocopherol, trolox, ascorbic acid (AA) and ascorbyl palmitate (AP), at levels of 50–200 ppm of antioxidant components, on colour (CIE L*a*b*), lipid (TBARS) and protein oxidation (thiol groups) in fresh, frozen and cooked pork patties during illuminated chill storage was investigated. Individual components of RE and TE were also tested. RESULTS: RE, TE, AP, tocopherol and trolox equally inhibited lipid oxidation in fresh and frozen patties, whereas for cooked patties RE was most effective. AA stimulated lipid oxidation. No dose effect in the range of 50–200 ppm was found for fresh and frozen patties, whereas for cooked patties higher doses of RE and TE more efficiently prevented lipid oxidation. Protein oxidation was hardly influenced by antioxidant treatment. Colour stability decreased as follows: tocopherol, AA and AP > RE and TE > trolox. Antioxidant properties of the extracts and their major antioxidant components were comparable. CONCLUSION: The relative effect of the antioxidants depends on the oxidation parameter assessed, the applied dose and the hydrophilic/lipophilic character. Copyright © 2009 Society of Chemical Industry     

Antioxidant activity of spice extracts in a liposome system and in cooked pork patties and the possible mode of action

Three experiments were conducted to assess the antioxidant efficacy of spice extracts in cooked meat. In experiment 1, antioxidant activity of 13 common spice extracts was screened in a liposome system. Six of the extracts (clove, rosemary, cassia bark, liquorice, nutmeg, and round cardamom), identified to have the greatest total phenolic contents, were strongly inhibitory of TBARS formation. In experiment 2, 2,2-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, ferric-reducing power, and metal chelation of these six spice extracts were evaluated. Clove exhibited the greatest reducing power, and all had strong DPPH scavenging activity. In experiment 3, clove, rosemary, and cassia bark extracts were further tested for in situ antioxidant efficacy. Cooked pork patties containing these spice extracts had markedly reduced TBARS formation and off-flavour scores but a more stable red colour, during storage. The results demonstrated strong potential of spice extracts as natural antioxidants in cooked pork products.     

Cholesterol and Lipid Oxidation Products in Cooked Meat as Affected by Raw-Meat Packaging and Irradiation and by Cooked-Meat Packaging and Storage Time

Aerobic packaging significantly increased cholesterol oxidation products (COPs) and thiobarbituric acid reactive substances (TBARS) in cooked turkey, pork, and beef patties after 7‐d storage, but vacuum packaging was very effective in preventing cholesterol and lipid oxidation. Packaging of meat after cooking had a much stronger effect on COPs formation than before cooking, and irradiation had only a minor effect. The amount of total COPs correlated well with TBARS in cooked meat. Turkey had the highest rates of COPs and TBARS formation and beef had the lowest rates after 7‐d storage, which were closely related to the fatty acid composition of meats. 7a‐hydroxycholesterol, 7p‐hydroxycholesterol, and 7‐ketocholesterol were the major COPs detected in all 3 cooked meat patties.     

Evaluation of the Antioxidant Potential of Hyssop (Hyssopus officinalis L.) and Rosemary (Rosmarinus officinalis L.) Extracts in Cooked Pork Meat

ABSTRACT: The objective of this work was to study the ability of rosemary and hyssop extracts to inhibit lipid oxidation and metmyoglobin formation in pork meat, thereby stabilizing meat color. We also evaluated their effects on iron release from the heme moiety of pork meat. Meat samples were blended with hyssop and rosemary extracts and cooked. The cooked meat was chopped into pieces and stored for 8 d at 4 °C. Heme iron, TBA values, metmyoglobin percentage, and meat color were calculated. Hyssop and rosemary were seen to inhibit lipid oxidation and degradation of heme pigments caused by cooking and storage. Both spices delayed metmyoglobin formation and stabilized the red meat color during storage of the cooked meat.     

Antioxidative effect of dietary grape pomace concentrate on lipid oxidation of chilled and long-term frozen stored chicken patties

Grape pomace concentrate (GPC) is a natural source of phenolic compounds with high antioxidant capacity. The effect of a diet containing GPC on lipid peroxidation levels (TBARS) and antioxidant capacity (ABTS method) of raw and cooked chicken breast meat patties stored in chilled conditions (4 °C) for 0, 3, 6, 13 and 20 days, and long-term frozen storage (6 months) was investigated. Chickens were fed GPC at levels of 0, 30 and 60 mg/kg from 3 to 6 weeks of age. Dietary GPC did not affect chicken performance. Lipid oxidation (TBARS value) was significantly increased by the storage time (0–20 days and 6 months of storage, respectively) in raw and cooked samples. Dietary GPC significantly caused an inhibitory effect on lipid oxidation of raw and cooked breast chicken patties compared with samples obtained from birds fed the control diet at 20 days and long-term frozen storage (6 months). Radical scavenging capacity was significantly increased at 20 days in cooked samples and significantly reduced at 6 months of storage in raw and cooked samples. The higher concentration of dietary GPC increased the ABTS values only in the raw samples. These results indicated that dietary grape pomace concentrate could be effective in inhibiting lipid oxidation of chilled and long-term frozen stored chicken patties.     

Quality characteristics of pork patties irradiated and stored in different packaging and storage conditions

Patties were made from pork loin, individually vacuum- or aerobic-packaged and stored either at 4 or -40°C. Refrigerated patties were irradiated at 0, 1.5, 3.0 or 4.5 kGy absorbed dose, and frozen ones were irradiated at 0, 2.5, 5.0, or 7.5 kGy. Samples were analyzed for lipid oxidation, volatile production and odor characteristics. Refrigerated samples were analyzed at 0, 1 and 2 weeks, and frozen ones after 0, 1.5 and 3 months of storage. With vacuum packaging, the lipid oxidation (TBARS) of both refrigerated and frozen patties was not influenced by irradiation and storage time except for the patties irradiated and refrigerated at 7.5 kGy. With refrigerated storage, panelists could detect irradiation odor at day 0, but not after 1 week at 4°C. With frozen storage, however, irradiation odor was detected even after 3 months of storage. With aerobic packaging, the TBARS of refrigerated pork patties increased with storage time. The TBARS of pork patties increased as irradiation dose increased at day 0, but the effect disappeared after 1 week at 4°C. Nonirradiated patties were preferred to the irradiated ones at day 0 because of the significant irradiation odor in the irradiated ones, but the off-odor disappeared after 1 week at 4°C. With frozen storage, patties irradiated at 7.5 kGy had higher TBARS than those irradiated at lower doses. Nonirradiated patties had higher preference scores than the irradiated ones for 1.5 months in frozen storage. Sulfur-containing compounds were responsible for most of the irradiation off-odor, but these volatilized quickly during storage under aerobic conditions. Overall, vacuum packaging was better than aerobic packaging for irradiation and subsequent storage of meat because it minimized oxidative changes in patties and produced minimal amounts of volatile compounds that might be responsible for irradiation off-odor during storage.     

Packaging and Irradiation Effects on Lipid Oxidation and Volatiles in Pork Patties

Raw-meat patties were prepared from three pork muscles, irradiated in different packaging environments, and stored for 0 or 3 days before cooking. Lipid oxidation by-products were formed in the raw meat during storage and the baseline lipid oxidation data of raw meat was used to measure the progression of lipid oxidation after cooking. Thiobarbituric acid-reactive substances (TBARS) and volatiles data indicated that preventing oxygen exposure after cooking was more important for cooked meat quality than packaging, irradiation, or storage conditions of raw meat. Propanal, pentanal, hexanal, 1 -pentanol, and total volatiles correlated highly (P < 0.01) with TBARS values of cooked meat. Hexanal and total volatiles represented the lipid oxidation status better than any other individual volatile components.     

The effect of dried galangal powder and its ethanolic extracts on oxidative stability in cooked ground pork

Thiobarbituric acid-reactive substances (TBARS) value, peroxide value (POV), conjugated diene and hexanal content were used to evaluate the effectiveness of dried galangal powder and its ethanolic extracts to increase oxidative stability in cooked ground pork during storage at 5 °C for 14 days. Dried galangal powder (0.05%, 0.10% and 0.15% w/w) and its ethanolic extracts (0.17%, 0.43% and 0.51% w/w) significantly (P<0.05) inhibited the formation of TBARS value, POV, conjugated diene and hexanal content in a dose-dependent manner where dried galangal powder at a concentration of 0.51% was the most effective; at the end of storage, TBARS values, POV, conjugated diene and hexanal content were 70.5%, 66.8%, 22.7% and 89.7%, respectively, less than the untreated sample. Addition of dried galangal powder to cooked ground pork was more effective than its ethanolic extract in controlling lipid oxidation. Furthermore, TBARS values and hexanal contents in cooked ground pork were highly correlated (r²=0.96; P<0.05). These results suggest that the application of dried galangal powder and its ethanolic extracts could enhance oxidative stability of meat or other lipid containing food systems.     

Lipid Oxidation, Volatiles and Color Changes of Irradiated Pork Patties Affected by Antioxidants

Changes were measured in TBARS, color, and volatiles of irradiated (4.5 kGy) pork patties with antioxidants (sesamol, quercetin, rutin, BHT, and rosemary oleoresin) during 7 days storage at 4°C. Irradiation accelerated lipid oxidation of raw pork during storage. However, irradiation before cooking did not influence lipid oxidation of cooked pork during storage. Sesamol, quercetin, and BHT were effective in both irradiated raw and cooked pork during 7-days storage. Rosemary oleoresin and rutin were effective only in irradiated raw pork for 3 days. Hexanal, propanal and higher boiling components were well correlated (P < 0.01) with TBARS in cooked pork. Generation of volatiles was reduced by sesamol and quercetin, but the effects of antioxidants on color changes of raw pork patties were minor and inconsistent.     

Oxidative stability of frozen pork patties: Effect of fluctuating temperature on lipid oxidation

The mobility of solutes in fat from pork belly, in lean pork belly and in lean pork longissimus dorsi, containing 1% NaCl was characterized by the ESR spin probe technique using the nitroxyl spin probes TEMPO and TEMPOL. The mobility of TEMPO in fat increased for temperature above -60 °C and the mobility of TEMPOL in lean meat increased for temperature above -40 °C. Temperatures for studying the effect of fluctuating temperatures during frozen storage of meat were selected based on the ESR characterization of the mobility of solutes. The oxidative stability of pork patties during frozen storage was measured as thiobarbituric acid reactive substances (TBARS), during storage at -10, -23 and -40 °C and with fluctuations between these temperatures, of pork patties made from pork loin (low fat 1.8%) or pork belly (high fat 22.7%). Lower storage temperatures resulted in less lipid oxidation, and temperature fluctuations between -40 and -23 °C and fluctuations between -23 and -10 °C resulted in oxidation intermediate to oxidation in samples stored at constant low or high temperatures of the fluctuation interval. The level of α-tocopherol was unaffected by the extent of oxidation in the frozen samples, an observation which is discussed in relation to differences in molecular mobility between oxygen and α-tocopherol.     

迷迭香提取物对真空包装熟猪肉饼抗氧化和抑菌效果的影响

以真空包装熟猪肉饼为试材,探讨不同质量分数迷迭香提取物的抗氧化、抑菌能力及其对肉饼品质的影响。将0.03%、0.06%和0.09%的迷迭香提取物分别添加到肉饼中,对肉饼在10 d冷藏期间的硫代巴比妥酸（thiobarbituricacid reactive substance,TBARS）值、菌落总数、挥发性盐基氮（total volatile basic nitrogen,TVB-N）含量、pH值、红度值（a*）和质构进行测定,并与0.02%二丁基羟基甲苯（butylated hydroxytoluene,BHT）进行比较。结果表明：添加迷迭香提取物的各处理组抗脂肪氧化能力高于空白对照组（P＜0.05）,迷迭香提取物添加量为0.09%的处理组在前7 d的冷藏过程中抑菌能力显著高于空白对照组（P＜0.05）。添加迷迭香提取物的各处理组TVB-N含量在冷藏4 d后显著低于空白对照组,而pH值在整个冷藏过程中均显著低于空白对照组（P＜0.05）。在冷藏1 d后,添加0.09%迷迭香提取物的肉饼a*值与空白对照组相比显著上升,而在冷藏7、10 d后,添加迷迭香提取物的各处理组a*值均显著升高（P＜0.05）。此外,添加迷迭香提取物的各处理组咀嚼性在冷藏4、7、10 d后显著升高,硬度在冷藏1、10 d后显著升高,迷迭香提取物添加量为0.09%的肉饼在冷藏4、7 d后硬度也显著提升（P＜0.05）。可见,迷迭香提取物能有效抑制真空包装熟猪肉饼的脂肪氧化及微生物生长,并且能在一定程度上改善其颜色和质构。     

Evaluation of the antioxidant potential of grape seed and bearberry extracts in raw and cooked pork

The effect of grape seed extract (GSE) and bearberry (BB), on lipid oxidation (TBARS, mg malondialdehyde (MDA)/kg muscle), colour (CIE ‘a’ redness value), pH, microbial status (log₁₀CFU colony forming units/g pork) and sensorial properties of cooked pork patties was investigated. GSE (0–1000 μg/g muscle) and BB (0–1000 μg/g muscle) were added to raw pork (M. longissimus dorsi) patties which were stored in modified atmosphere packs (MAP) (75% O₂:25% CO₂) for up to 12 days at 4 °C. Cooked pork patties were stored in MAP (70% N₂:30% CO₂) for up to 4 days at 4 °C. Mesophilic plate counts and pork pH were unaffected by GSE and BB. GSE and BB addition decreased (P < 0.05) lipid oxidation (TBARS) in raw pork patties on days 9 and 12 of storage, relative to controls. Antioxidant activity of GSE and BB was observed in cooked pork patties demonstrating the thermal stability of GSE and BB. The ‘a’ redness values of raw and cooked pork patties marginally increased with increasing GSE concentration. The sensory properties of cooked pork patties were unaffected by GSE and BB addition. Results obtained demonstrate the potential for using health promoting nutraceuticals in meat and meat products.     

槲皮素和NaCl添加量对牦牛肉饼蛋白质和脂质氧化的影响

为研究槲皮素（Quercetin,Q）和不同NaCl添加量（0%、2%、4%、6%,m/m）对牦牛肉饼在贮藏过程中蛋白质和脂质氧化的影响,测定了牦牛肉饼在冷藏15 d期间的pH值、色差、羰基含量、表面疏水性、色氨酸荧光强度、二聚酪氨酸含量、过氧化值（Peroxide Value,POV）和硫代巴比妥酸反应物（Thiobarbituric Acid Reactive Substances,TBARS）值。结果表明,随着NaCl添加量增加,pH值增加（P<0.05）,L*、a*和b*值先增加后降低（P<0.05）;添加槲皮素后咸肉饼的pH值（P<0.05）、a*和b*值增加（P<0.05）、L*值降低（P<0.05）。添加NaCl使肉饼的羰基、表面疏水性、二聚酪氨酸、POV值和TBARS值增加（P<0.05）,色氨酸荧光强度减小（P<0.05）;但槲皮素处理使咸肉饼的色氨酸荧光强度、二聚酪氨酸、POV值及TBARS值降低,使4% NaCl（质量分数）肉饼的羰基含量降低了27.80%;表面疏水性在0~2% NaCl（质量分数）添加量下进一步增加（P<0.05）,而在4%~6% NaCl添加量下降低（P<0.05）。该研究表明,NaCl能促进牦牛肉饼蛋白质和脂质氧化,但加入槲皮素可有效缓解肉饼氧化。该结果可为槲皮素作为肉制品天然抗氧化剂提供参考。     

Use of natural food/plant extracts: cloudberry (Rubus Chamaemorus), beetroot (Beta Vulgaris “Vulgaris”) or willow herb (Epilobium angustifolium) to reduce lipid oxidation of cooked pork patties

The antioxidant activity of plant extracts (100 and 500 mg/kg) from cloudberry, willow herb and beetroot on thiobarbituric acid (TBA) reactive substances (TBARS) development and hexanal content of cooked pork patties was investigated. Pure quercetin, rutin and caffeic acid were tested in parallel for comparison. The most potent antioxidants on stabilizing oxidation were cloudberry extract and quercetin. The lowest antioxidant activity was found with the addition of pure rutin to the meat. Caffeic acid showed an intermediate activity. At a concentration of 100 mg/kg, beetroot and willow herb extracts showed an antioxidant activity on TBARS and hexanal contents similar to that observed for caffeic acid during 3 days of refrigerated display, while cloudberry extract was as potent as quercetin. At a concentration of 500 mg/kg, beetroot and willow herb extract stabilized hexanal production of cooked pork patties after 6 days of refrigerated storage in a way comparable to that observed for pure quercetin and cloudberry extract. TBARS numbers were well correlated with hexanal content in cooked pork patties on day 3 of refrigerated storage. However, hexanal production and TBARS numbers were not highly correlated in samples with the highest level of beetroot (500 mg/kg). Hexanal production was inhibited by the high level of beetroot, but TBARS production was not, perhaps because the red color of beetroot extract interfered with the determination of the pink TBA chromogen.     

Antioxidative effect of added tea catechins on susceptibility of cooked red meat,poultry and fish patties to lipid oxidation

The comparative antioxidant activity of added tea catechins on susceptibility of cooked and overwrapped red meat (beef and pork), poultry (chicken, duck and ostrich) and fish (whiting and mackerel) to lipid oxidation was investigated. Fresh meats, poultry and fish, purchased from a local market, were trimmed to remove bones, skin and visible fat and minced through a 4-mm plate. The minced muscle from each species was treated with either 1% NaCl (S), 300 mg tea catechins kg⁻¹ minced muscle (TC) or 1% NaCl plus 300 mg tea catechins kg⁻¹ minced muscle (TCS). Control minced muscle samples (C) contained neither NaCl nor tea catechins. Patties (50 g), prepared from treated and untreated minced muscle, were cooked until the core temperature reached 75°C, cooled down to room temperature and held in a refrigerated (4°C) and illuminated (616 lux) display cabinet for 10 days. Oxidative stability (TBARS) was measured at 3-day intervals. The susceptibility of cooked patties to lipid oxidation was closely related to lipid content, concentration of unsaturated fatty acids and presence of iron in different species. Addition of NaCl to raw minced muscle significantly (P<0.05) promoted lipid oxidation for cooked patties regardless of species sources. Tea catechins added at a level of 300 mg kg⁻¹ minced muscle significantly (P<0.01) inhibited the pro-oxidation caused by NaCl and controlled lipid oxidation for all cooked muscle patties examined. Tea catechins at concentrations greater than 300 mg kg⁻¹ were necessary to reduce oxidation for mackerel patties containing high levels of lipids and unsaturated fatty acids. The high affinity of tea catechins for the lipid bilayers of muscle and the radical scavenging abilities of tea catechins may be possible mechanisms to explain the oxidative stability in cooked muscle foods.     

The influence of the anticaking agent potassium ferrocyanide and salt on the oxidative stability of frozen minced pork meat

The anticaking agent potassium ferrocyanide, K(4)Fe(CN)(6), was found to affect lipid oxidation in frozen, minced pork meat both in 'normal' concentrations, when added together with food grade salt to yield 2 % NaCl in the product, and in 'unrealistic' high concentrations added separately or together with analytical grade salt. The level of K(4)Fe(CN)(6) obtained from adding 2 % food grade salt accelerated the development of lipid hydroperoxides, but affected the development of TBARS to a lesser degree. High level of K(4)Fe(CN)(6) seems to protect hydroperoxides from degradation to secondary lipid oxidation products measured as TBARS. The use of salt with the anticaking agent, K(4)Fe(CN)(6), in meat processing should be reconsidered for each product since it may enhance lipid oxidation. A mechanism for mediation by the Fe(CN) (6)(4-)Fe(CN) (6)(3-) redox couple of pigment-catalysed lipid oxidation is suggested, based on an observed correlation between oxymyoglobin oxidation (measured as tristimulus colorimetric parameter, a) and lipid oxidation (measured as TBARS) for the frozen pork patties.     

Antioxidant activity of Carob fruit extracts in cooked pork meat systems during chilled and frozen storage

The purpose of this study was to evaluate the effect of adding condensed tannins in the form of non-purified (Liposterine^®) or purified (Exxenterol^®) extracts obtained from Carob fruit to prevent lipid cooked pork meat systems from oxidising during chilling and frozen storage. The antioxidant activity of these extracts was compared with that of α-tocopherol. Meat lipid alteration was evaluated as thiobarbituric acid reactive substances content (TBARS) and polar material-related triglyceride compounds followed by high-performance size-exclusion chromatography (HPSEC). TBARS levels were lower (P < 0.05) in samples containing Liposterine (LM), Exxenterol (EM), and α-tocopherol (TM) than in control sample (CM) under chilled storage. TBARS formation was similar (P > 0.05) for LM and EM but lower (P < 0.05) than for TM. Polar material increased several times in all samples, but significantly less in TM and EM than in LM. Thermal oxidation compounds determined by HPSEC were lower (P < 0.05) in EM than in LM or TM. The changes in polar material were proportionally smaller after six months frozen storage than after chilled storage, with Exxenterol displaying the highest antioxidant protection. Therefore Carob fruit extracts can be successfully used to reduce fat alteration in cooked pork meat at chilled and frozen temperatures.