Antioxidative effect of added dried Holy basil and its ethanolic extracts on susceptibility of cooked ground pork to lipid oxidation

Efficacy of varying concentrations of dried Holy basil powder and its ethanolic extracts in retarding oxidative rancidity was tested with cooked ground pork. The development of lipid oxidation products during 14 days refrigerated storage (5 °C) was evaluated by means of thiobarbituric acid-reactive substances (TBARS) value, peroxide value (POV), conjugated diene and hexanal content. In the amounts studied, dried Holy basil powder and its ethanolic extract significantly (P < 0.05) inhibited the formation of TBARS, peroxide, conjugated dienes and hexanal in a dose-dependent manner. The oxidation process was significantly (P < 0.05) influenced by the type of antioxidant and its concentration. Addition of dried Holy basil powder to cooked ground pork was more effective in inhibiting lipid oxidation than its ethanolic extracts. Additionally, TBARS values and hexanal contents in cooked ground pork were highly correlated (r² = 0.95; P < 0.05) with each other.     

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.     

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.     

Effect of antioxidants on stabilization of meat products fortified with n-3 fatty acids

The effects of an n-3 oil emulsion, with and without added antioxidants, on lipid oxidation in n-3 polyunsaturated fatty acid (PUFA)-fortified meat products were studied. An emulsion of n-3 PUFAs was prepared (25% algal oil, 2.5% whey protein isolates, 10mM sodium citrate, 0.2% potassium sorbate, 500ppm of 70% mixed tocopherols, 100μM EDTA, pH 3, pasteurized at 75°C for 30min) and incorporated into fresh ground turkey, and fresh pork sausage (20% fat) to achieve a concentration of 500mg n-3 PUFA/110g meat. An antioxidant combination containing rosemary (0.2% w/w; radical quencher), citrate (0.5% w/w; sequestrant) and erythorbate (1g/kg product; reductant) was prepared and incorporated into ground turkey patties (5cm dia, 1.5cm thick) or fresh pork sausages (5cm dia, 1.5cm thick). Meat products were stored at 4°C or -18°C and analyzed for color (L*, a*, b* values), lipid oxidation (TBARS and lipid hydroperoxides) and n-3 PUFA profile. a* Values of refrigerated ground turkey patties decreased with storage, and an antioxidant combination effect was observed after 4 days (P<0.05). For fresh pork sausages at 4°C, control+antioxidant (CON+ANTI), and n-3+antioxidant (n-3+ANTI) groups showed greater a* values than controls (CON) indicating that the antioxidant combination stabilized meat color. TBARS and lipid hydroperoxides of both n-3 PUFA-enhanced meat products increased with storage (P<0.05); there were no significant changes in TBARS or lipid hydroperoxides for treatments containing the antioxidant combination (P<0.05). The actual level of n-3 PUFA incorporation in both meat products was greater than 87%; n-3 PUFA concentrations did not change within any treatment during storage (P>0.05). These results provide support for including antioxidant protection in n-3 PUFA fortified meat products.     

Effect of Antioxidants and Cooking on Stability of n-3 Fatty Acids in Fortified Meat Products

ABSTRACT: This study was carried out to determine the effect of processing and cooking on n-3 polyunsaturated fatty acid (PUFA) stability and to determine the efficacy of antioxidants (ANTI) to minimize lipid oxidation in cooked n-3 PUFA-fortified meat products. An emulsion of n-3 PUFAs (25% algal oil) was incorporated into ground turkey, pork sausages, or restructured hams (500 mg n-3 PUFA/110 g meat) with or without an "antioxidant cocktail" containing citrate (0.5% w/w), erythorbate (1 g/kg product), and rosemary (0.2% w/w). Ground turkey and pork sausages were frozen 2 d, then cooked to 71°C, and stored at 4°C for 2 d. Cooked, restructured hams were sliced, vacuum packaged, and stored at 4°C, or frozen and thawed with subsequent storage at 4°C. Treatments were CON (control), n-3 (n-3 PUFAs), CON + ANTI and n-3 + ANTI. Products were analyzed for color, lipid oxidation (TBARS and peroxide values), and n-3 PUFA profile. TBARS of n-3 PUFA-fortified treatments in ground turkey and pork sausages increased with storage ( P < 0.05); there were no changes in TBARS for CON + ANTI and n-3 + ANTI groups ( P > 0.05). For restructured hams nitrite curing appeared to delay lipid oxidation such that antioxidant treatment effects were unobservable ( P > 0.05). Overall recovery of n-3 PUFAs after heat processing was 69% to 85%, and there was no effect of storage on n-3 PUFA concentration in raw or cooked products ( P > 0.05). Sensory scores for n-3 treated restructured hams were lower than controls ( P < 0.05). Results suggested that cooking resulted in some losses of n-3 PUFAs in fortified meat products and that an "antioxidant cocktail" protected against lipid oxidation during subsequent storage in non-cured meat products.     

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。     

Lipid and protein oxidation of α-linolenic acid-enriched pork during refrigerated storage as influenced by diet supplementation with olive leaves (Olea europea L.) or α-tocopheryl acetate

The objective of this study was to evaluate the effect of diet supplementation with olive leaves or α-tocopheryl acetate on lipid and protein oxidation of raw and cooked n-3 enriched-pork during refrigerated storage. Enrichment of pork with α-linolenic acid through diet supplementation with linseed oil enhanced (p≤0.05) lipid oxidation in both raw and cooked chops but had no effect (p>0.05) on protein oxidation during refrigerated storage while decreasing (p≤0.05) the sensory attributes of cooked pork. Diet supplementation with olive leaves or α-tocopheryl acetate had no effect (p>0.05) on the fatty acid composition of pork but decreased (p≤0.05) lipid oxidation while exerting no effect (p>0.05) on protein oxidation in both raw and cooked α-linolenic acid-enriched chops stored and chilled for 9days. Moreover, olive leaves and α-tocopheryl acetate supplemented at 10g/kg and 200mg/kg diet, respectively, exerted (p≤0.05) a beneficial effect on the sensory attributes of cooked α-linolenic acid-enriched pork chops.     

Control of Clostridium perfringens spores by green tea leaf extracts during cooling of cooked ground beef, chicken, and pork

We investigated the inhibition of Clostridium perfringens spore germination and outgrowth by two green tea extracts with low (green tea leaf powder [GTL]; 141 mg of total catechins per g of green tea extract) and high (green tea leaf extract [GTE]; 697 mg of total catechins per g of extract) catechin levels during abusive chilling of retail cooked ground beef, chicken, and pork. Green tea extracts were mixed into the thawed beef, chicken, and pork at concentrations of 0.5, 1.0, and 2.0% (wt/ wt), along with a heat-activated (75 degrees C for 20 min) three-strain spore cocktail to obtain a final concentration of approximately 3 log spores per g. Samples (5 g) of the ground beef, chicken, and pork were then vacuum packaged and cooked to 71 degrees C for 1 h in a temperature-controlled water bath. Thereafter, the products were cooled from 54.4 to 7.2 degrees C in 12, 15, 18, or 21 h, resulting in significant increases (P < 0.05) in the germination and outgrowth of C. perfringens populations in the ground beef, chicken, and pork control samples without GTL or GTE. Supplementation with 0.5 to 2% levels of GTL did not inhibit C. perfringens growth from spores. In contrast, the addition of 0.5 to 2% levels of GTE to beef, chicken, and pork resulted in a concentration-and time-dependent inhibition of C. perfringens growth from spores. At a 2% level of GTE, a significant (P < 0.05) inhibition of growth occurred at all chill rates for cooked ground beef, chicken, and pork. These results suggest that widely consumed catechins from green tea can reduce the potential risk of C. perfringens spore germination and outgrowth during abusive cooling from 54.4 to 7.2 degrees C in 12, 15, 18, or 21 h of cooling for ground beef, chicken, and pork.     

Antioxidant properties of selected Oriental non-culinary/nutraceutical herb extracts as evaluated in raw and cooked meat

Ethanol extracts of white peony (WP), red peony (RP), sappanwood (SW), Moutan peony (MP), rehmania (RE) or angelica (AN) were individually added to ground goat meat at 0.5-2.0% (g dry extract/100 g final meat sample), and raw and cooked samples were aerobically refrigerated for 0, 3 or 6 days. These extracts and rosemary extract (RO) were also individually added to salted or unsalted ground beef at 0.01-0.25% and refrigerated as raw or cooked patties. WP, RP, RE, SW and MP markedly reduced (P<0.05) lipid oxidation in cooked-stored goat meat. With 0.25% of WP, RP, SW, MP or RO in beef, lipid oxidation during storage was minimal in raw and cooked patties (plain or salted); raw patty redness values at day 6 were higher (P<0.05) for SW, WP, RP or MP than RO treatment or the control. At 0.01%, SW was more antioxidative (P<0.05) than the other extracts.     

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.     

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.     

Influence of Polyphosphate on Storage Stability of Restructured Beef and Pork Nuggets

Influence of polyphosphate on sensory and chemical characteristics of battered and breaded, cooked, restructured beef and pork nuggets was evaluated over 20 wk storage. Beef and pork nuggets manufactured with polyphosphate had lower (P<0.05) initial thiobarbituric acid (TBA) values than those manufactured without polyphosphate (controls); and values remained lower (P<0.05) than control treatments over 20 wk of storage. Sensory panelists detected less (P<0.05) off-flavor in pork nuggets manufactured with polyphosphate than nuggets in control treatments. Detection of off-flavor in pork nugget control treatments may be attributed to higher TBA values (increased lipid oxidation) in the pork product. Addition of polyphosphate protected nuggets from lipid oxidation and subsequent off-flavor development.     

Enhancement of the nutritional status and quality of fresh pork sausages following the addition of linseed oil, fish oil and natural antioxidants

Fresh pork sausages (pork shoulder, pork back fat, water, rusk and seasoning) were manufactured where 15% of the pork back fat was substituted with linseed oil (LO) or fish oil (FO). Green tea catechins (GTC) and green coffee antioxidant (GCA) were added to both LO (LGTC 200 and LGCA 200) and FO (FGTC 200 and FGCA 200) substituted sausages at a level of 200 mg/kg. Raw and cooked pork sausages were either over-wrapped with oxygen permeable film (aerobic storage) or stored in modified atmosphere packages (MAP) containing 80% O₂:20% CO₂ or 70% N₂:30% CO₂, respectively for 7 days at 4 °C. Effects on fatty acid profiles, lipid oxidation, colour and sensorial properties were investigated. α-Linolenic acid increased from 1.34% (control) to 8.91% (LO) and up to 11.2% (LGTC 200 and LGCA 200). Addition of fish oil increased levels of EPA from 0.05% (control) to 2.83% (FO), 3.02% (FGTC 200) and 2.87% (FGCA 200) and DHA levels increased from 0.04% (control) to a maximum of 1.93% (FGTC 200). Lipid oxidation was low in raw and cooked linseed oil containing sausages. GTC (200 mg/kg) significantly (P < 0.05) reduced lipid oxidation in raw fish oil containing sausages after 7 days of storage. Colour parameters in raw pork sausages were unaffected by the packaging atmosphere. L^* lightness values were lower (P < 0.05) in LGTC 200 and a^* redness values lower (P < 0.05) in LGTC 200 and FGTC 200 after 7 days of storage. Sensory scores of cooked pork sausages were unaffected by linseed oil addition. Flavour and overall acceptability scores in cooked fish oil containing sausages were improved by GTC addition. Results obtained demonstrate potential for the production of nutritionally enhanced fresh pork sausages.     

Antioxidant activity of carnosine in cooked ground pork

Carnosine (0·5-1·5%) reduced (P < 0·05) the formation of thiobarbituric acid reactive substances (TBARS) in cooked unsalted ground pork after 7 days of storage at 4°C. The antioxidant activity of carnosine was less in cooked salted ground pork, with only 1·5% carnosine inhibiting (P < 0·05) TBARS formation during refrigerated storage. The antioxidant activity of carnosine in cooked salted and unsalted ground pork was greater than those of the lipid-soluble free radical scavengers, butylated hydroxytoluene and α-tocopherol (P < 0·05) but less than that of sodium tripolyphosphate (P < 0·05). These data suggest that carnosine could be used to reduce the oxidative deterioration of cooked salted and unsalted ground pork.     

Comparison of antioxidant effects of milk mineral, butylated hydroxytoluene and sodium tripolyphosphate in raw and cooked ground pork

The antioxidant effects of 0.5-2.0% milk mineral (MM) was tested in raw and cooked ground pork stored at 2?°C or -20?°C, compared to butylated hydroxytoluene (BHT) and sodium tripolyphosphate (STP). TBA numbers were low and not different between raw meat treatments. TBA numbers were lower (P<0.01) for cooked treatments with MM or STP compared to controls or treatments with BHT. Experiments were also done to determine acceptability of pork samples with various TBA values, and to determine effect of holding time before serving on TBA values. Cooked pork patties held at 71?°C for 90 or 120 min had higher (P<0.05) TBA values than patties held for 0-60 min. Thus patties could be warmed for 60 min after cooking without significantly increasing TBA number. For paired-preference sensory testing, patties were cooked and stored at 2?°C for 0, 1, 2 and 3 days to obtain TBA numbers of 0.4, 1.5, 3.4 and 3.9 respectively. Panelists preferred (P<0.001) patties with TBA number <0.5, compared to patties with TBA numbers >1.4.     

THE ANTIOXIDATIVE POTENTIAL OF LYOPHILIZED CITRUS PEEL EXTRACT IN DIFFERENT MEAT MODEL SYSTEMS DURING STORAGE AT 20C

Antioxidative potential of lyophilized citrus (Citrus unshiu) peel extract in raw and cooked meat systems was investigated. Beef pork, chicken, and salmon patties were prepared without (control), with lyophilized citrus peel extract (0.1%, NICP), and with 20 kGy-irradiated, lyophilized citrus peel extract (0.1%, ICP). TBARS value showed that the addition of lyophilized citrus peel (NICP or ICP) inhibited the development of lipid oxidation of raw and cooked meat patties during storage for 8 days at 20C (P<0.05) except for raw chicken patty. Hunter color a*-values of the cooked meat patties treated with NICP or ICP were higher than those of the control (P<0.05). Irradiation of citrus peel extract did not show any notable changes in its antioxidant effect in the meat systems. Thus, the lyophilized citrus extract could be used as one of the natural antioxidants with the potential of cost-effectiveness and is environmentally friendly.     

Enhancement of the nutritional status and quality of fresh pork sausages following the addition of linseed oil,fish oil and natural antioxidants

Fresh pork sausages (pork shoulder, pork back fat, water, rusk and seasoning) were manufactured where 15% of the pork back fat was substituted with linseed oil (LO) or fish oil (FO). Green tea catechins (GTC) and green coffee antioxidant (GCA) were added to both LO (LGTC 200 and LGCA 200) and FO (FGTC 200 and FGCA 200) substituted sausages at a level of 200 mg/kg. Raw and cooked pork sausages were either over-wrapped with oxygen permeable film (aerobic storage) or stored in modified atmosphere packages (MAP) containing 80% O₂:20% CO₂ or 70% N₂:30% CO₂, respectively for 7 days at 4 °C. Effects on fatty acid profiles, lipid oxidation, colour and sensorial properties were investigated. α-Linolenic acid increased from 1.34% (control) to 8.91% (LO) and up to 11.2% (LGTC 200 and LGCA 200). Addition of fish oil increased levels of EPA from 0.05% (control) to 2.83% (FO), 3.02% (FGTC 200) and 2.87% (FGCA 200) and DHA levels increased from 0.04% (control) to a maximum of 1.93% (FGTC 200). Lipid oxidation was low in raw and cooked linseed oil containing sausages. GTC (200 mg/kg) significantly (P < 0.05) reduced lipid oxidation in raw fish oil containing sausages after 7 days of storage. Colour parameters in raw pork sausages were unaffected by the packaging atmosphere. L¹ lightness values were lower (P < 0.05) in LGTC 200 and a¹ redness values lower (P < 0.05) in LGTC 200 and FGTC 200 after 7 days of storage. Sensory scores of cooked pork sausages were unaffected by linseed oil addition. Flavour and overall acceptability scores in cooked fish oil containing sausages were improved by GTC addition. Results obtained demonstrate potential for the production of nutritionally enhanced fresh pork sausages.     

Evaluation of the antioxidant potential of natural food/plant extracts as compared with synthetic antioxidants and vitamin E in raw and cooked pork patties

Antioxidant potential for previously identified optimum levels of aloe vera (AV), fenugreek (FGK), ginseng (G), mustard (M), rosemary (R), sage (S), soya protein (SPI), tea catechins (TC) and whey protein concentrate (WPC) were evaluated in raw and cooked patties manufactured from frozen pork. The optimum levels determined were: AV (0.25%), FGK (0.01%), G (0.25%), M (0.10%), R (0.10%), S (0.05%), SPI (0.10%), TC (0.25%) and WPC (4%). Test ingredients were evaluated against synthetic antioxidants butylated hydroxyanisole/butylated hydroxytoluene (BHA/BHT) (0.01%) and a supplemented meat containing natural antioxidant, α-tocopherol (1000 mg α-tocopheryl acetate/kg feed). Ranking the decreasing antioxidant effectiveness of added ingredients in raw patties on day 9 showed that: Control>G>SPI>FGK>AV>M>WPC>S>α-tocopherol>R>TC>BHA/BHT. Cooking resulted in a four-fold increase in TBARS values over raw patties with TC being the most effective antioxidant having significantly (P<0.001) lower TBARS values than the cooked control on days 3, 6 and 9. Ranking of decreasing antioxidant effectiveness of added ingredients showed that: M>SPI>G>FGK>α-tocopherol>AV>control>S>BHA/BHT>R>WPC>TC. BHA/BHT had the most beneficial effect on cooked meat redness with Hunter 'a' values being significantly (P<0.05) higher than the control on days 3, 6 and 9. Ranking of Hunter 'a' values for added test ingredients showed that FGK>WPC>control>R>BHA/BHT>α-tocopherol>TC>AV>SPI>M>G>S on day 9. Hunter 'L' and 'b' values showed no significant trend over the storage period in either raw or cooked patties. The pH values of both raw and cooked pork control patties and products containing added test antioxidants were variable and while a number of trends were observed, no significant differences were recorded between samples.     

Evaluation of the Ability of Eleutherine americana Crude Extract as Natural Food Additive in Cooked Pork

ABSTRACT:  The scavenging activities of crude ethanolic extract from  Eleutherine americana , on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl free radicals were investigated. The results revealed that the extract produced IC₅₀ values of 8.4 μg/mL and 0.78 mg/mL on DPPH and hydroxyl free radicals, respectively. The total phenolic content of the extract was determined using the Folin–Ciocalteu reagent and the crude extract yielded high phenolic content of 4.56 μmol gallic acid equivalent per milligram dried extract. The extract, at different concentrations, was incorporated into pork, cooked in the microwave, and stored at 4 °C for 9 d. The crude extract demonstrated antioxidant activity, which increases with increased extract concentrations and retarded lipid oxidation in the cooked pork. Antibacterial activity of the extract against  Staphylococcus aureus  in the cooked pork revealed that at a concentration of 10.8 mg/100 g, the extract reduced the bacterial population by 0.57 log compared to control at 9 d of storage. The sensory results revealed that the pork samples treated with the extract and the control sample were not significantly different from day 0 to 6; however, on day 9 the treatments were significantly scored higher than the control. Furthermore, addition of the extract led to an increase in the redness values of the pork and this was acceptable from the sensory point of view.  E. americana  crude extract could be a promising novel antioxidant to prevent lipid oxidation and a potential natural color enhancer of red meat and meat products.