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You searched for: Journal Journal of agricultural and food chemistry Remove constraint Journal: Journal of agricultural and food chemistry Publication Year 1998 Remove constraint Publication Year: 1998 Source 1998 v.46 no.7 Remove constraint Source: 1998 v.46 no.7
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1. Additional studies on flavor components of corn tortilla chips

Author:
Buttery, R.G.; Ling, L.C.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2764-2769
ISSN:
0021-8561
Subject:
tortillas; snacks; grain products; flavor compounds; volatile compounds; isolation; chemical composition; spectral analysis
Abstract:
... Volatile components from tortilla chips were isolated by high flow dynamic headspace sampling using a closed loop system with excess anhydrous sodium sulfate and trapping the volatiles on Tenax. Capillary GC-MS was used to identify the components. Major volatiles identified included 2-methylpyrazine, 1-hydroxy-2-propanone, 4-vinylguaiacol, 2-acetyltetrahydropyridine, (E,E)- and (E,Z)-2,4-decadiena ...
DOI:
10.1021/jf980125b

2. Aggregation of myofibrillar proteins in hake, sardine, and mixed minces during frozen storage

Author:
Huidobro, A.; Mohamed, G.F.; Tejada, M.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2601-2608
ISSN:
0021-8561
Subject:
protein aggregates; hake; sardines; Sardina pilchardus; mixtures; myofibrils; myosin; frozen storage; extraction
Abstract:
... The effect of frozen storage on the loss of extractability of natural actomyosin (NAM) with 0.6 M NaCl (P1) was studied in hake (Merluccius merluccius), sardine (Sardina pilchardus), and mixed minces in varying proportions stored for up to 1 year at -20 degrees C. The objective was to ascertain the types of bonds established among the proteins. The unextracted NAM was treated with different extrac ...
DOI:
10.1021/jf970962y

3. An endoglycosidase from grape berry skin of Cv. M. Alexandria hydrolyzing potentially aromatic disaccharide glycosides

Author:
Gunata, Z.; Blondeel, C.; Vallier, M.J.; Lepoutre, J.P.; Sapis, J.C.; Watanabe, N.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2748-2753
ISSN:
0021-8561
Subject:
grapes; glycosidases; glycosides; hydrolysis; pH; temperature; purification; flavor compounds
Abstract:
... We present evidence on the presence of an endoglycosidase in grape skins able to split the heterosidic linkage of disaccharide glycosides, releasing disaccharide and aglycon. Its extraction from grape skins (cv. Muscat of Alexandria) was possible with the use of a detergent (poly(ethylene glycol)). The enzyme was purified about 1000-fold successively by chromatography on DEAE Sepharose CL 6B, CM 2 ...
DOI:
10.1021/jf980084j

4. Antimutagens in the Brazilian folk medicinal plant carqueja (Baccharis trimera Less)

Author:
Nakasugi, T.; Komai, K.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2560-2564
ISSN:
0021-8561
Subject:
mutagenicity; Baccharis; medicinal plants; traditional medicine; plant extracts; flavones; structure-activity relationships; chemoprevention; mutation; apigenin; Brazil
Abstract:
... Antimutagens from carqueja (Baccharis trimera Less., Compositae), a Brazilian folk medicinal plant used to treat liver disease and rheumatism, were examined. The methanol extract prepared from aerial parts of this plant strongly reduced the mutagenicity of 3-amino-1-methyl-5H-pyrido[4,3-b]-indole, when Salmonella typhimurium TA98 was used in the presence of rat liver microsomal fraction. The antim ...
DOI:
10.1021/jf9711045

5. Antinutrient reduction and enhancement in protein, starch, and mineral availability in fermented flour of finger millet (Eleusine coracana)

Author:
Antony, U.; Chandra, T.S.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2578-2582
ISSN:
0021-8561
Subject:
Eleusine coracana; fermented foods; fermentation; antinutritional factors; tannins; phenols; trypsin inhibitors; protein content; mineral content; starch; nutrient content; nutrient availability; in vitro digestibility; India
Abstract:
... Finger millet, a highly nutritious millet consumed by populations in South India, is a rich source of minerals and dietary fiber in addition to primary nutrients. However, it also has nutrient binding components such as phytate, phenols, tannins, and trypsin inhibitors. Fermentation of finger millet flour using endogenous grain microflora showed a significant reduction of these components (phytate ...
DOI:
10.1021/jf9706639

6. Antioxidant capacity as influenced by total phenolic and anthocyanin content, maturity, and variety of Vaccinium species

Author:
Prior, R.L.; Cao, G.; Martin, A.; Sofic, E.; McEwen, J.; O'Brien, C.; Lischner, N.; Ehlenfeldt, M.; Kalt, W.; Krewer, G.; Mainland, C.M.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2686-2693
ISSN:
0021-8561
Subject:
blueberries; antioxidants; phenolic compounds; anthocyanins; ascorbic acid; weight; titratable acidity; Vaccinium angustifolium; Vaccinium virgatum; Vaccinium corymbosum; Vaccinium myrtillus; cultivars; geographical distribution; chemical constituents of plants; species differences; Michigan; New Jersey; Oregon
Abstract:
... Different cultivars of four Vaccinium species [Vaccinium corymbosum L (Highbush), Vaccinium ashei Reade (Rabbiteye), Vaccinium angustifolium (Lowbush), and Vaccinium myrtillus L (Bilberry)] were analyzed for total phenolics, total anthocyanins, and antioxidant capacity (oxygen radical absorbance capacity, ORAC). The total antioxidant capacity of different berries studied ranged from a low of 13.9 ...
DOI:
10.1021/jf980145d

7. Autoxidation in the formation of volatiles from glucose-lysine

Author:
D'Agostina, A.; Negroni, M.; Arnoldi, A.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2554-2559
ISSN:
0021-8561
Subject:
glucose; lysine; volatile compounds; heat treatment; oxidation; antioxidants; oxidants; pH; principal component analysis
Abstract:
... The formation of volatile compounds from an aqueous glucose-lysine model system heated in the presence of either a free radical initiator (pro-oxidant) or an antioxidant was investigated. alpha-Tocopherol, 2,6-di-tert-butyl-4-methylphenol (BHT), and rosemary extract were used as antioxidants, and alpha,a'-azobis(isobutyronitrile) (AIBN) was used as a free radical initiator. The experiments were pe ...
DOI:
10.1021/jf980053o

8. Bioluminescent bacterial genotoxicity test for fatty acid derivatives and heated oils

Author:
Sun, T.S.C.; Stahr, H.M.; Love, J.A.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2682-2685
ISSN:
0021-8561
Subject:
cooking fats and oils; soybean oil; cholesterol; heat treatment; oxidation; fatty acids; fatty acid esters; genotoxicity; bacteria; bioluminescence; rapid methods; chlorinated fatty acids; testing
Abstract:
... The Mutatox test (the commercial name for a bioluminescent bacterial genotoxicity test), which has been proved to be a good alternative to the Ames test, was used in this study to test the genotoxicity of fatty acid derivatives and heated oils. This test allows either pure or complex compounds to be rapidly screened for genotoxicity. Five different column fractions isolated from autoxidized methyl ...
DOI:
10.1021/jf970647b

9. Bovine hepatic metabolism of aflatoxin B1

Author:
Kuilman, M.E.M.; Maas, R.F.M.; Judah, D.J.; Fink-Gremmels, J.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2707-2713
ISSN:
0021-8561
Subject:
hepatocytes; cattle; isolation; cell culture; aflatoxins; metabolites; metabolism; enzymes; enzyme activity; high performance liquid chromatography; species differences
Abstract:
... Differences in the expression and catalytic activity of hepatic biotransformation enzymes account for species differences in xenobiotic metabolism, including that of aflatoxin B1 (AFB1). The main objectives of this study were (1) to define the procedure for isolation and culture of bovine hepatocytes, (2) to characterize the biotransformation capacity of bovine hepatocytes for AFB1, and (3) to dev ...
DOI:
10.1021/jf980062x

10. Comparison of solid-phase extraction methods for the cleanup of cholesterol oxidation products

Author:
Ulberth, F.; Rossler, D.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2634-2637
ISSN:
0021-8561
Subject:
cholesterol; oxidation; milk fat; foods; extraction; analytical methods; quantitative analysis
Abstract:
... Cholesterol oxidation products (COPs) may accumulate in foods of animal origin during processing or storage. As they represent a potential health risk, a need exists for rapid and efficient methods to monitor the occurrence of COPs in the human diet. Methods involving saponification to remove triacylglycerols suffer from artifact formation; therefore, alternatives involving solid-phase extraction ...
DOI:
10.1021/jf980012s

11. Comparison of the effects of high pressure and thermal treatments on the casein micelles in goat's milk

Author:
Law, A.J.R.; Leaver, J.; Felipe, X.; Ferragut, V.; Pla, R.; Guamis, B.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2523-2530
ISSN:
0021-8561
Subject:
goat milk; casein; pressure treatment; heat treatment; whey protein; calcium phosphates; ultrastructure; micelles
Abstract:
... The influence of thermal and high-pressure treatments on caprine casein micellar structure and, in particular, on the micellar serum distribution of whey proteins, caseins, and calcium phosphate was studied by ultracentrifugation and transmission electron microscopy. Quantification of the major whey proteins and caseins was achieved using reverse-phase HPLC, and the extent of denaturation of the w ...
DOI:
10.1021/jf970904c

12. Computer simulation of flavor release from solid foods in the mouth

Author:
Harrison, M.; Campbell, S.; Hills, B.P.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2736-2743
ISSN:
0021-8561
Subject:
foods; flavor; odors; mouth; saliva; mastication; deglutition; particle size distribution; food composition; algorithms; mathematical models
Abstract:
... A computer simulation describing flavor release from solid foods in the mouth is presented. The rate-limiting step for flavor release is assumed to be the transport of flavor volatiles across the food-saliva interface, which can be described by the stagnant-layer theory of mass transfer. Saliva flow, mastication, and swallowing are incorporated into the model. The mastication process is simulated ...
DOI:
10.1021/jf980090f

13. CO2 treatment of zucchini squash reduces chilling-induced physiological changes

Author:
Serrano, M.; Pretel, M.T.; Martinez-Madrid, M.C.; Romojaro, F.; Riquelme, F.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2465-2468
ISSN:
0021-8561
Subject:
zucchini; cold storage; chilling injury; carbon dioxide; putrescine; spermidine; spermine; abscisic acid
Abstract:
... Zucchini squash showed chilling injury (CI) damage as pitting on 93% of their surface after 12 days at 2 degrees C, and a 2-2.5-fold increase in putrescine levels in both skin and pulp was detected during storage (from 162 and 38 to 320 and 98 nmol g-1 of fresh weight, respectively). Abscisic acid concentration increased mainly in the skin. Treatments with CO2 prior to storage at 2 degrees C were ...
DOI:
10.1021/jf970864c

14. Deep-fat frying modifies high-fat fish lipid fraction

Author:
Candela, M.; Astiasaran, I.; Bello, J.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2793-2796
ISSN:
0021-8561
Subject:
water content; deep fat frying; cooking; cooking fats and oils; sunflower oil; sardines; salmon; chemical composition; fatty acids; eicosapentaenoic acid; docosahexaenoic acid; cholesterol; mackerel
Abstract:
... The lipid composition of three high-fat fishes (sardines, mackerel, and salmon) was analyzed to study the effect of deep-fat frying with sunflower oil and warmholding (65 degrees C, 3 h). Only sardines increased total fat content with cooking. Saturated fatty acids content decreased, especially in sardines and mackerel, mostly because of the palmitic acid reduction. Raw sardines and mackerel prese ...
DOI:
10.1021/jf9709616

15. Determination of propoxur residues in whole body brown tree snakes

Author:
Primus, T.M.; Tawara, J.N.; Goodall, M.J.; Brooks, J.E.; Savarie, P.J.; Johnston, J.J.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2647-2650
ISSN:
0021-8561
Subject:
snakes; propoxur; pesticide residues; extraction; chemical analysis; detection; quantitative analysis; high performance liquid chromatography; Boiga irregularis; reversed-phase high performance liquid chromatography; Guam
Abstract:
... Propoxur was extracted from brown tree snakes (Boiga irregularis) and analyzed by reversed-phase high-performance liquid chromatography. Propoxur was quantified by UV absorbance at 270 nm and fluorescence with excitation at 225 nm and emission at 305 nm. Recovery data were determined by analyzing propoxur-fortified blank homogenized tissue. The mean recovery of propoxur in whole body brown tree sn ...
DOI:
10.1021/jf971009w

16. Determination of the carnosic acid content in wild and cultivated Rosmarinus officinalis

Author:
Hidalgo, P.J.; Ubera, J.L.; Tena, M.T.; Valcarel, M.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2624-2627
ISSN:
0021-8561
Subject:
rosemary; Rosmarinus officinalis; wild plants; leaves; antioxidants; diterpenoids; photoperiod; seasonal variation; environmental factors; chemical constituents of plants
Abstract:
... The concentration of carnosic acid in a representative selection of leaves from wild and cultivated populations of Rosmarinus officinalis was determined by reversed-phase HPLC following extraction with supercritical carbon dioxide. Different sources of variability including season, genetics, leaf age, and growing origin (wild or cultivated) were considered. Variability in the carnosic acid content ...
DOI:
10.1021/jf970974j

17. Determination of volatile organic selenium compounds from the Maillard reaction in a selenomethionine-glucose model system

Author:
Tsai, J.H.; Hiserodt, R.D.; Ho, C.T.; Hartman, T.G.; Rosen, R.T.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2541-2545
ISSN:
0021-8561
Subject:
Maillard reaction; Maillard reaction products; glucose; selenium; organic compounds; volatile compounds; chemical structure; selenomethionine
Abstract:
... In the past, biomedicine, toxicology, and other related disciplines have made some progress with regard to the detrimental and beneficial effects of selenium in biological systems. Therefore, it is of interest to determine the chemical structure and occurrence of organoselenium compounds generated in food systems via the Maillard reaction. The Maillard reaction involves the reaction of amino acids ...
DOI:
10.1021/jf971050z

18. Dynamic release of diacetyl from liquid gelatin in the headspace

Author:
Bakker, J.; Baudaud, N.; Harrison, M.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2714-2720
ISSN:
0021-8561
Subject:
gelatin; liquids; diacetyl; flavor; mathematical models; viscosity; mass transfer
Abstract:
... The effect of gelatin concentration and stirring rate on the dynamic release of diacetyl was investigated, using headspace analysis for the duration of the experiment. Both liquid and headspace were stirred in a sealed system. An increase in gelatin concentration was shown to affect the initial release rate, as defined by the amount of diacetyl released over the first few minutes of the experiment ...
DOI:
10.1021/jf970994l

19. Effect of breathing and saliva flow on flavor release from liquid foods

Author:
Harrison, M.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2727-2735
ISSN:
0021-8561
Subject:
foods; liquids; flavor; emulsions; mouth; saliva; mass transfer; mathematical models
Abstract:
... Using the penetration theory of interfacial mass transfer, mathematical models have been developed to describe flavor release from liquid foods in the mouth, which incorporates the effects of breathing and saliva dilution. It has been assumed that the rate-limiting step for flavor release is resistance to mass transfer across the liquid-gas interface. This model has been applied to two types of li ...
DOI:
10.1021/jf9710591

20. Effect of bubble velocity and pH step changes on the foam fractionation of sporamin

Author:
Chai, J.; Loha, V.; Prokop, A.; Tanner, R.D.
Source:
Journal of agricultural and food chemistry 1998 v.46 no.7 pp. 2868-2872
ISSN:
0021-8561
Subject:
sweet potatoes; plant proteins; beta-amylase; fractionation; pH; velocity; storage proteins
Abstract:
... Foam fractionation can be employed to concentrate and separate sporamin (ipomoein) from a sweet potato protein-water extract. In this foam fractionation study, the bulk solution pH and the air superficial velocity, V0, were the two primary control variables. It was determined that the protein separation ratio is strongly dependent on the bulk solution pH, with the highest sporamin recovery occurri ...
DOI:
10.1021/jf970929b