Progress 10/01/98 to 09/30/04
Outputs
The total phenolic acid content and antioxidant activities of fenugreek, green tea, black tea, grape seed, ginger, rosemary, gotu kola, and ginkgo extracts ranged from 24.8-92.5 mg chlorogenic acid equivalent/g dry material, and 3.4-86.3%, respectively. In another study, non-hydrolyzed and hydrolyzed green tea extracts demonstrated similar antioxidant activities ranging from 41.0-88.8% and 45.9-88.2%, respectively. The effectiveness of synthetic and natural antioxidants, green tea, commercial grape seed extract/combinations with varying concentrations, and TBHQ on physicochemical properties on non-irradiated and irradiated chicken breast meats stored at -20 degrees Celsius for 9 months was investigated. Fresh boneless skinless chicken breast meats were vacuum infused with antioxidants: green tea/grape seed extracts alone/ in combination, and TBHQ. The irradiation was 3.0 kGy. Irradiation had no significant effect on pH, water holding capacity (p less than 0.05), but
increased the redness (p less than 0.05). Irradiation increased maximum shear force, hardness, and chewiness (p less than 0.05) of cooked meat. Infusion of plat extract/s combination into chicken breasts increased lightness and decreased redness (p less than 0.05) as well as hardness and maximum shear force. TBARS values for 0-9 months of storage at -20 degrees Celsius ranged from 1.21-3.83 and 1.38-4.84 mg malondialdehyde /100g chicken for non-irradiated and irradiated raw chicken, respectively, while in cooked chicken the values ranged from 2.18-16.27 and 2.45-27.30 mg malondealdehyde /100g for non-irradiated and irradiated chicken, respectively. The carbonyl content in meat lipid ranged from 1.7-2.0 and 1.7-2.49 micromole acetophenone/10g of non-irradiated and irradiated chicken raw meat respectively.
Impacts
Selected plant extracts can be used to retard lipid oxidation in pure lipids and lipid-based food products. Infusion of chicken meat with antioxidants and selected plant extracts is an effective method to minimize lipid oxidation caused by irradiation. These extracts and individual phenolic constituents hold promise as radioprotectors in other tissues.
Publications
- Taha Rababah. August 2004.Ph.D. Maintenance of raw and Cooked Ready-To-Eat Product Quality of Infused Poultry Meats With selected Plant Extracts During Electron Beam Irradiation and After Storage. Ph.D. Dissertation. Department of Food Science, University of Arkansas, Fayetteville.
- Rababah, T., N.S. Hettiarachchy, and R. Horax. 2004. Total Phenolics and Antioxidant Activities of Fenugreek, Green Tea, Black Tea, Grape Seed, Ginger, Rosemary, Gotu Kola, and Ginkgo Extracts, Vitamin E, and tert-Butylhydroquinone . Agric. Food Chem., 52 (16), 5183-5186.
- Rababah, T., N. S. Hettiarachchy, and R. Horax. 2004. Total phenolics and antioxidant activities of selected plant extracts. IFT Annual Meeting and Food Expo, Las Vegas, Nevada, July 12-16. Book of abstracts. 67B-8, p.162.
- Rababah, T., N. S. Hettiarachchy, R. Horax, D.H. Zhu, M.G. Johnson, J. Dickson, and S. Niebuhr. 2004. Effect of electron beam irradiation and storage at 5oC on thiobarbituric acid reactive substances (TBARS) and carbonyl contents in chicken breast meat infused with antioxidants and selected plant extracts. IFT Annual Meeting and Food Expo, Las Vegas, Nevada, July 12-16. Book of abstracts. 67C-4, p.167.
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Progress 01/01/03 to 12/31/03
Outputs
Seventeen varieties of cowpeas grown in Arkansas were analyzed for their phenolic constituents using HPLC. Protocatechuic acid was identified as the major phenolic acid present in esterified forms. The amount of protocatechuic acid increased from trace: 3.6 to 9.3-92.7 mg/ g flour in the 17 varieties of cowpeas after hydrolysis. Six other phenoloc acids, including, p-hydroxybenzoic acid, caffeic acid, p-coumaric acid, ferulic acid, 2,4 dimethoxybenzoic acid, and cinnamic acid, were also identified. These phenolic acids were evenly distributed mainly in the free acid forms at <7 mg/100g of flour. Total phenolic contents determined using Folin - Ciocalteu's reagent were largely different among the 17 varieties, ranging from 34.6 to 376.6 mg/100g flour. A comparison of the HPLC chromatograms of the 17 cowpea phenolics before and after alkali hydrolysis indicated the conversion of a pattern with evenly distributed peaks to one with a single major peak for protocatechuic
acid, suggesting that the chromatograms before hydrolysis better represent the identities of the cowpea varieties. The total phenolics and antioxidant activities of green tea, black tea, fenugreek, grape seed, gotukola, rosemary, ginger, and ginko extracts were determined. Green tea and grape seed extracts were also combined to evaluate their synergistic effect. The total phenolic acid of the plant extracts ranged from 24.8-92.5 mg of chlorogenic acid equivalent (CAE)/g dry material. Antioxidant activity of methanolic extracts determined by conjugated diene measurement of methyl linoleate ranged from 3.4 to 86.3%. Antioxidant activity using chicken fat, by an oxidative stability instrument followed a similar trend as with conjugated diene measurement and ranged from 4.6 to 10.2 h, but higher than that of control (2.3 h) (induction time).
Impacts
The levels of protocatechuic acid in cowpeas are much higher compared to reported data for other legumes. The predominant amount of protocatechuic acid present in hydrolyzed cowpea phenolics suggests major role the compound may play in the nutraceutical and functional properties of cowpeas in the diets. Methyl linoleate (MeLo) and oxidative stability instrument (OSI) systems can be used effectively to determine antioxidant activities in model and food systems.
Publications
- Cai, R., N.S. Hettiarachchy and M. Jalaluddin. 2003. High Performance Liquid chromatography determination of phenolic constituents in 17 varieties of cowpeas. J. Agricultural Food Chemistry. 51, 1623-1627.
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Progress 01/01/02 to 12/31/02
Outputs
Our results showed that cow pea, black tea, green tea, rice bran and fenugreek ethanol extracts inhibited 92.3, 95.0, 99.0, 98.3, and 72.4% in the formation of conjugated diene respectively; while black tea, green tea, ginger, and coriander water extracts inhibited 92.2, 93.7, 92.7, and 91.3% respectively. Commercial water extracts from grape seed, gotu kola, ginkgo leaf, and rosemary inhibited 99.8, 99.0, 91.2, and 98.8% respectively. Both BHA and TBHQ inhibitions were 100%. The effectiveness of synthetic antioxidants and natural plant extracts with varying concentrations on physicochemical properties during and after irradiation (3.5 kGy) of chicken breast meats at 5 degree C for 0, 3, 6, 9, and 12 days were investigated. Alpha-tocopherol infused breast meats had lower water-holding capacity after irradiation. Although irradiation enhanced lipid oxidation, TBARS values decreased with increased concentrations of antioxidants. TBHQ was the most effective antioxidant
in retarding lipid oxidation. Green extract at 1,500, 2,500, and 3,500 ppm was more effective than any other extracts in minimizing oxidation. Egg albumen coatings with natural antioxidants fenugreek, rosemary, and vitamin E were evaluated for their antioxidant activity in diced raw and cooked poultry breast meat. Coatings were applied using vacuum tumbling and a boiling method. Coated samples and uncoated controls were evaluated for their malondialdehyde and reactive substances content as a measure of lipid oxidation via the thiobarbituric acid test. Cooked egg albumen-coated samples showed reactive compound changes of 1.56 x (ten to the minus seven) M for 4 d of refrigeration, compared to 1.59 x (ten to the minus six) M changes in the cooked control. Raw control changed by 1.97 x (ten to the minus six) versus 1.67 x (ten to the minus six) M for rosemary coated samples. In raw and cooked studies egg albumen coating showed most effective against lipid oxidation.
Impacts
The natural extracts examined in this study, cow pea, black & green tea, rice bran, and fenugreek extracts all showed effectiveness in minimizing lipid oxidation. These extracts have the potential to extend shelf-life in lipid-containing food products. Green tea, fenugreek and rosemary extracts, alpha tocopherol, and TBHQ can be effectively used to minimize lipid oxidation in irradiated poultry products. Egg albumin coating can be effectively used to prevent rancidity in diced cooked and raw chicken cubes.
Publications
- Armitage, D., N.S. Hettiarachchy, and A. Monsoor. (2002). Natural antioxidants as a component of an egg albumen film in the reduction of lipid oxidation in cooked and uncooked poultry. J. Food Sci. 67(2)631-634.
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Progress 01/01/01 to 12/31/01
Outputs
Our investigation demonstrated the effectiveness of natural antioxidants in the extension of poultry shelf when applied as a protein film additive. Analysis of soybean oil with antioxidant addition using an Oxidative Stability Instrument demonstrated the activity of natural antioxidants investigated by extending oxidation times by 50% or more. Film solutions were prepared containing the natural antioxidant E, Rosemary extract, and fenugreek extract in concentrations ranging from 1000 ppm to 3000 ppm. For the experiment control solutions of de-ionized water, plasticizer and protein were prepared. Raw chicken meat was cubed into 3/4 inch pieces and treated with antioxidant film solutions. One set was boiled for 10 minutes in the film solutions with and without antioxidant to prepare cooked product. The second set was treated by vacuum marination to prepare raw product. Samples were stored at 5 degrees C, and -20 degrees C and monitored for lipid oxidation using
thiobarbituric acid test. Analysis showed oxidation inhibition by antioxidant addition in comparison to control treatments in refrigerated samples by 30% more, with vitamin E showing the highest inhibition in cooked samples and fenugreek extract showing the highest inhibition in raw samples. The antioxidant activity of 70% ethanol fenugreek extract was determined by Oxidative Stability Instrument. Films produced with soy protein isolate (SPI), wheat gluten (WG), whey protein isolate (WPI), carageenan and CMC were evaluated for mechanical and physical properties. Based on the antioxidant activity and film's mechanical and physical properties fenugreek extract and TBHQ were selected for incorporation into SPI/carageenan film solutions. The SPI/carageenan films containing fenugreek extract/TBHQ coated cooked beef cubes were effective in minimizing lipid oxidation.
Impacts
The natural antioxidants examined in this study, fenugreek extract, rosemary extract and vitamin E all showed effectiveness in minimizing rancidity. These natural antioxidants can be used to minimize rancidity and extend shelf life of poultry products. The natural antioxidant fenugreek extract is a potential source for extending the shelf life of beef products.
Publications
- Armitage, D, Hettiarachchy, N.S. and Monsoor, A. 2001. Natural antioxidants as a component of an egg albumen film in the reduction of lipid oxidation in cooked and uncooked poultry. J. Food Sci. In Press.
- Al-Ameri, F., and Hettiarachchy, N.S. 2001. Edible film as carrier of antioxidants. IFT Annual Meeting and Food Expo. Book of Abstracts. 30A-6, p. 49.
- Al-Ameri, F. 2001. Physical properties of edible films with and without antioxidants and the effectiveness of selected film coatings on the shelf life stability of beef cubes. M.S. Thesis. P.85.
- Ko, S., Janes, M.E., Hettiarachchy, N.S., and Johnson, M.G. 2001. Physical and chemical properties of edible films containing nisin and their action against Listeria monocytogenes. J. Food Sci. 66 (7):1006-1011.
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Progress 01/01/00 to 12/31/00
Outputs
Analysis of soybean oil with antioxidant addition using oxidative stability instrument demonstrated the activity of natural antioxidants investigated by extending oxidation times by 50% or more. Film solutions were prepared containing the natural antioxidants vitamin E, Rosemary extract, and fenugreek extract in concentrations ranging from 1000 to 3000 ppm. For the experiment control solutions of deionized water, plasticizer and protein were prepared. Raw chicken breast meat was cubed into three-fourth inch pieces and treated with the solutions. One set was boiled for 10 minutes in the film solutions with and without antioxidant to prepare cooked product. The second set was treated by vacuum marination to prepare raw product. Samples were stored at 5 degrees Celsius, -5 degrees Celsius and freeze-dried and stored at -5 degrees Celsius and monitored for lipid oxidation using the thiobarbituric acid test. Analysis showed oxidation inhibition by antioxidant addition in
comparison to control treatments in refrigerated samples by 30% or more, with vitamin E showing the highest in cooked samples and fenugreek extract showing the highest inhibition in raw samples. Research has been initiated on the maintenance of raw product quality of marinated poultry breasts with antioxidants during and after electron beam irradiation.
Impacts
The antioxidant coating is likely to be effective in extending refrigerated storage of poultry product.
Publications
- No publications reported this period
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Progress 01/01/99 to 12/31/99
Outputs
Last year I reported that conditions will be optimized to evaluate the synergistic antioxidant effect of rice bran protein, soy protein containing genestein, and fenugreek. Combinations of these three did not show synergistic antioxidant activity. Two proposals tilted, " Development of edible egg albumen films for frozen chicken products", and "Maintenance of raw product quality of marinated poultry breasts with antioxidants during and after electron beam irradiation" received competitive funding through U.S. Poultry and Egg Association, and Food Safety Consortium. Conditions were optimized to produce edible films with egg albumen protein that has desirable mechanical and water vapor permeability properties. Two films were selected, and antioxidants (fenugreek, rosemary, vitamin E and synthetic antioxidants) were incorporated in the film forming solutions. Base line data were collected to initiate a shelf life study of film coated chicken cubes with and without
antioxidants to evaluate the effectiveness of antioxidants in films to minimize/prevent rancidity. This study is currently in progress. Research will be initiated on the maintenance of raw product quality of marinated poultry breasts with antioxidants during and after electron beam irradiation.
Impacts
(N/A)
Publications
- No publications reported this period
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Progress 01/01/98 to 12/31/98
Outputs
Fenugreek (Trigonella foenumgraecum) extract (FE) with and without protein polymers (PP), rice bran protein (RBP), soy protein (SP) and soy protein containing genestein (SPG) were evaluated for antioxidant activities and synergistic effects by the active oxygen method. Synthetic antioxidants BHA and TBHQ were also included for comparison. The synthetic antioxidants were used at 200 ppm (maximum level allowed for synthetic antioxidants. Fenugreek extract, PP, RBP, SP, SPG, BHA and TBHQ had maximum induction times (hrs) of 8.8, 7.5, 9.0, 7.0, 9.8, 8.6 and 18.0 at 500, 700, 500, 1000, 200 and 200 ppm, respectively. Combinations of RBP + SPG and FE + SPG gave enhanced induction times (12 and 15 hrs), but did not have a synergistic effect. Currently, research is in progress in optimizing levels of RBP, SPG and FE to evaluate synergistic effects. Since the collaborative research proposal that was submitted to the National Research Initiative Grant proposal did not get
funded, the antioxidant activity of elite oregano will be initiated when funds become available.
Impacts
(N/A)
Publications
- No publications reported this period
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Progress 01/01/97 to 12/31/97
Outputs
Rice bran extract and various soy protein hydrolzates with and without fenugreek extract (FE) were evaluated for antioxidant activities and synergistic effect by the Active Oxygen Method. Synthetic antioxidant BHA was also included for comparison. Rice bran extract (RBE) and BHA had similar antioxidant activities (induction times: 8.7 and 8.6) at 1000 and 200 ppm (maximum level allowed for BHA is 200 ppm), respectively. No synergistic effect was observed when a combination of RBE + FE or RBE + FE + soy protein hydrolyzates were used. Antioxidant activity of FE was weaker (induction time (IT):7.5) in comparison to RBE (IT:8.7) and BHA (IT:8.6). Of all the soy protein hydrolyzates tested, only alcalase hydrolyzed soy protein peptides had an IT of 9.0 at 1000 ppm, which is significantly higher than BHA (IT:8.6 at 200 ppm). Soy whey proteins had negligible antioxidant activity. Research is in progress to investigate antioxidant activity of protein polymers. Research will
be initiated to investigate the antioxidant activity of elite oregano extract and its application if the collaborative project submitted to the National Research Initiative Grant proposal gets funded.
Impacts
(N/A)
Publications
- No publications reported this period
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Progress 01/01/96 to 12/30/96
Outputs
Natural antioxidants were extracted from defatted ground fenugreek using 60% ethyl alcohol. The effectiveness of fenugreek extract in preventing lipid oxidation in raw and cooked beef patties was evaluated. Ground beef patties containing fenugreek extracts (500 ppm) or synthetic antioxidants (200 ppm) and with no added antioxidants (control) were prepared. Cooked patties were prepared by heating to an internal temperature of 70 degrees C. Raw and cooked patties were stored at 4 degrees C. Storage stabilities of beef patties were evaluated at 0. 3, 6, 9, and 12 days using thiobarbituric acid values, induction time for lipid oxidation measured by oxidative stability instrument, and Hunterlab color measurements. Thiobarbituric acid (TBA) values of raw or cooked samples containing fenugreek extracts were lower than controls (P<0.05). TBA value of raw and cooked controls increased from 0.12 to 0.18 after 6 days of storage. While TBA value of raw and cooked patties
containing fenugreek extract increased from 0.10 to 0.13 after 6 days, that of samples containing synthetic antioxidant was bellow 0.05 throughout the storage period. Fenugreek extracts delayed the induction period of oxidative rancidity. Induction time for controls were 2.55, and 4.20 hr for raw and cooked patties, respectively. Induction time for raw and cooked samples with fenugreek extract were 5.10, and 14.95 hr, respectively. Samples containing fenugreek extracts had lower hunterlab "a" and higher "b" values.
Impacts
(N/A)
Publications
- HETTIARACHCHY, N. S., GLEN, K. C., GNANASAMPNDAM, R., AND JOHNSON, M. G. 1996. NATURAL ANTIOXIDANT EXTRACT FROM FENUGREEK (TRIGONELLA FOENUMGRAECUM) FOR GROUNDBEEF PATTIES. J. FOOD SCI. 61:516.
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Progress 01/01/95 to 12/30/95
Outputs
Concern over safety of synthetic antioxidants has stimulated interests in antioxidant extracts from natural sources. Antioxidant extracts from natural sources including rice bran, and fenugreek (Trigonella foenumgraecum), were prepared and evaluated. Water and ethyl alcohol were used as solvent media to prepare the extracts. Extracts of rice bran in ethyl alcohol showed enhanced antioxidant effect compared to the control as indicated by a delayed induction period for lipid oxidation measured using an Oxidative Stability Instrument. The antioxidant effect also increased with increase in the concentration of alcohol in the extraction medium. Antioxidant extracts prepared from fenugreek, a popular spice from Asia, was investigated for use in ground beef patties. Beef patties were cooked to a minimum internal temperature of 70oC, cooled, vacuum packaged, stored at 4oC, and evaluated at 0, 3, 6, 9, and 12 days. Thiobarbituric acid values of both raw and cooked samples
containing fenugreek extracts were lower than the control (P<0.05). Fenugreek extracts delayed the induction period of oxidative rancidity when compared to the controls. Color of raw patties were affected due to the addition of fenugreek extracts, while no differences were observed in psychrotrophic bacterial counts. Preparation of natural antioxidant extracts from rice bran and fenugreek promote value added use of agricultural co- products and under-utilized plant sources.
Impacts
(N/A)
Publications
- NO PUBLICATIONS REPORTED THIS PERIOD.
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Progress 01/01/94 to 12/30/94
Outputs
Concern over safety of synthetic antioxidants has stimulated interests in antioxidant extracts from natural sources. Natural antioxidant extracts from fenugreek (Trigonella foenumgraecum), and rice bran were prepared and evaluated. Solvent systems including water, ethyl alcohol at different concentrations were used to prepare the extracts. Other variables included heat treatment of raw material, and time and temperature of extraction. Extracts prepared from fenugreek were investigated for antioxidative properties in ground meat. Beef patties were cooked to a minimum internal temperature of 155oF, cooled, vacuum packaged, stored at 4oC, and evaluated at 0, 3, 6, 9, and 12 days. Thiobarbituric acid (TBA) values of samples containing fenugreek extracts were lower than control. The samples containing fenugreek extracts also had delayed induction period as measured with Oxidative Stability Instrument (OSI). Fenugreek extracts at 500 and 1000 ppm, showed better oxidative
stability than control. Extracts of rice bran in ethyl alcohol showed increased antioxidant effect compared to control as indicated by higher induction periods measured by OSI in those samples. The effect was found to increase as the concentration of alcohol increased. Extracts from 60% ethyl alcohol showed the longest induction period of 10.10 hr. compared to the control (7.55 hr).
Impacts
(N/A)
Publications
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