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981.
The concentrations of individual and total glucosinolates were measured in four types of Portuguese cabbage and in one hybrid white cabbage before and after cooking. Typical Portuguese culinary procedures include boiling the cabbage for 10 min but for particular kale types the leaves are first shredded then boiled for 5 min (Caldo verde). Analysis of the fresh cabbage, cooked leaves and cooking water showed that the glucosinolate content of the cabbages is reduced by more than 50%. Almost all of this loss is accounted for as intact glucosinolates in the cooking water, normally used for soups in Portugal. 相似文献
982.
V Santé-Lhoutellier N Robert JF Martin P Gou M Hortós J Arnau A Diestre M Candek-Potokar 《Meat science》2012,92(4):354-359
This study aimed to evaluate the effects of PRKAG3 Ile199Val and CAST Arg249Lys and CAST Ser638Arg polymorphisms on the quality traits of the French dry-cured ham Jambon de Bayonne and their interaction with salt reduction. Significant (p<0.05) and suggestive associations (p<0.10) between the polymorphisms and several quality traits of dry-cured ham, mainly related to processing and textural properties, were found. PRKAG3 Ile/Val and CAST 249Lys/638Arg presented the highest scores for sensory and processing properties, whatever the salt content. 相似文献
983.
Satisfying America's Fruit Gap: Summary of an Expert Roundtable on the Role of 100% Fruit Juice 下载免费PDF全文
Carol Byrd‐Bredbenner Mario G. Ferruzzi Victor L. Fulgoni III Robert Murray Elizabeth Pivonka Taylor C. Wallace 《Journal of food science》2017,82(7):1523-1534
The 2015 to 2020 Dietary Guidelines for Americans (DGAs) recognize the role of 100% fruit juice in health and in helping people meet daily fruit recommendations and state that 100% fruit juice is a nutrient‐dense beverage that should be a primary choice, along with water and low‐fat/fat‐free milk. The DGAs note that children are consuming 100% fruit juice within recommendations (that is, 120 to 180 mL/d for children aged 1 to 6 y and 236 to 355 mL/d for children aged 7 to 18 y). Evidence shows that compared to nonconsumers, those who consume 100% fruit juice come closer to meeting daily fruit needs and have better diet quality. In children, 100% fruit juice is associated with increased intakes of nutrients such as vitamin C, folate, and potassium. When consumed within the DGA recommendations, 100% fruit juice is not associated with overweight/obesity or childhood dental caries and does not compromise fiber intake. Preliminary data suggest that polyphenols in some 100% fruit juices may inhibit absorption of naturally occurring sugars. Given its role in promoting health and in helping people meet fruit needs, experts participating in a roundtable discussion agreed that there is no science‐based reason to restrict access to 100% fruit juice in public health nutrition policy and programs such as the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Reducing or eliminating 100% fruit juice could lead to unintended consequences such as reduced daily fruit intake and increased consumption of less nutritious beverages (for example, sugar‐sweetened beverages). 相似文献
984.
The effect of high pressure on the log reduction of six strains of Escherichia coli O157:H7 and five serovars of Salmonella enterica was investigated in tryptic soy broth, sterile distilled water, and commercially sterile orange juice (for Salmonella) and apple cider (for E. coli). Samples were subjected to high-pressure processing treatment at 300 and 550 MPa for 2 min at 6 degrees C. Samples were plated onto tryptic soy agar directly after pressurization and after being held for 24 h at 4 degrees C. At 300 MPa, little effect was seen on E. coli O157:H7 strains, while Salmonella serovars varied in resistance, showing reductions between 0.26 and 3.95 log CFU/ml. At 550 MPa, E. coli O157:H7 strains exhibited a range of reductions (0.28 to 4.39 log CFU/ml), while most Salmonella populations decreased beyond the detection limit (> 5-log CFU/ml reduction). The most resistant strains tested were E. coli E009 and Salmonella Agona. Generally, bacterial populations in fruit juices showed larger decreases than did populations in tryptic soy broth and distilled water. E. coli O157:H7 cultures held for 24 h at 4 degrees C after treatment at 550 MPa showed a significant log decrease as compared with cultures directly after treatment (P < or = 0.05), while Salmonella serovars did not show this significant decrease (P > 0.05). All Salmonella serovars tested in orange juice treated at 550 MPa for 2 min at 6 degrees C and held for 24 h showed a > 5-log decrease, while E. coli O157:H7 strains require a higher pressure, higher temperature, longer pressurization, or a chemical additive to achieve a 5-log decrease. 相似文献
985.
Determination of a kinetic factor influencing the vaporescence of flavour components from wort 下载免费PDF全文
Hans Scheuren Frank Schuster Robert Koukol Karl Sommer Frank‐Jürgen Methner Michael Dillenburger 《Journal of the Institute of Brewing》2016,122(2):310-316
The current article considers the question of whether vaporescence during wort boiling affects evaporation via the vapour side mass transport. Thereby the vaporization of unwanted flavour components (such as dimethyl sulphide or benzaldehyde) can be influenced negatively or positively, which affects the amount of energy needed. The question is pursued by pre‐calculation and experimental validation of the vapour side mass stream at the evaporation surface: for that purpose vaporescence trials were carried out in a plant trial, with both benzaldehyde and water as pure substances and a mixture of benzaldehyde and water in an infinite solution (xi < 10?6). Trial parameters were process temperature and volume stream of the gas phase. The results obtained by the trials with pure substances enable pre‐calculation of vapour side mass transport. Then, pre‐calculation is compared with the results of the mixture trials and thus verified. As a result it has to be stated that vaporescence in the brew houses is pre‐calculable and that the mass transport has an impact on the vaporescence at the vapour side boundary layer. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
986.
Maja Mikulic‐Petkovsek Franci Stampar Robert Veberic Helena Sircelj 《Journal of food science》2016,81(8):C1928-C1937
Sugars, organic acids, carotenoids, tocopherols, chlorophylls, and phenolic compounds were quantified in fruit of 4 wild growing Prunus species (wild cherry, bird cherry, blackthorn, and mahaleb cherry) using HPLC‐DAD‐MSn. In wild Prunus, the major sugars were glucose and fructose, whereas malic and citric acids dominated among organic acids. The most abundant classes of phenolic compounds in the analyzed fruit species were anthocyanins, flavonols, derivatives of cinnamic acids, and flavanols. Two major groups of anthocyanins measured in Prunus fruits were cyanidin‐3‐rutinoside and cyanidin‐3‐glucoside. Flavonols were represented by 19 derivatives of quercetin, 10 derivatives of kaempferol, and 2 derivatives of isorhamnetin. The highest total flavonol content was measured in mahaleb cherry and bird cherry, followed by blackthorn and wild cherry fruit. Total phenolic content varied from 2373 (wild cherry) to 11053 mg GAE per kg (bird cherry) and ferric reducing antioxidant power antioxidant activity from 7.26 to 31.54 mM trolox equivalents per kg fruits. 相似文献
987.
Melissa Fuster Ellen Messer Robert F. Houser Hedi Deman Patricia Palma De Fulladolsa Odilia I. Bermudez 《Food and Foodways: Explorations in the History and Culture of》2013,21(4):288-314
This study presents an assessment of local definitions and perceptions concerning healthy eating through a study in four resource-poor border communities in El Salvador. The study included focus groups, key-informant interviews, and observations of the food environment. Local definitions of healthy eating elicited through focus groups were compared to the national Salvadoran dietary guidelines recommendations. The comparison revealed several areas of overlap (including the importance of dietary variety, fruits, and vegetables, among others) and omissions (mention of limiting sweets/candy, salt, sugar, and alcohol). Focus group participants expressed concerns over the origin of their foods and whether food contained harmful chemicals. These conversations also revealed the contradictions between nutrition knowledge and preferences for foods classified as unhealthy. This article concludes with a discussion about barriers to healthy eating identified in the focus groups and through the food environment assessment. 相似文献
988.
Quinone emissions from gasoline and diesel motor vehicles 总被引:2,自引:0,他引:2
Jakober CA Riddle SG Robert MA Destaillats H Charles MJ Green PG Kleeman MJ 《Environmental science & technology》2007,41(13):4548-4554
Gas- and particle-phase emissions from gasoline and diesel vehicles operated on chassis dynamometers were collected using annular denuders, quartz filters, and PUF substrates. Quinone species were measured using O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine derivatization in conjunction with gas chromatography-mass spectrometry and high-performance liquid chromatography-mass spectrometry. Nine quinones were observed, ranging from C6 to C16. New species identified in motor vehicle exhaust include methyl-1,4-benzoquinone, 2-methyl-1,4-naphthoquinone (MNQN), and aceanthrenequinone. Gas-phase motor vehicle emissions of quinones are also reported for the first time. Six gas-phase quinones were quantified with emission rates of 2-28 000 microg L(-1) fuel consumed. The most abundant gas-phase quinones were 1,4-benzoquinone (BON) and MNQN. The gas-phase fraction was > or = 69% of quinone mass for light-duty gasoline emissions, and > or = 84% for heavy-duty diesel emissions. Eight particle-phase quinones were observed between 2 and 1600 microg L(-1), with BQN the most abundant species followed by 9,10-phenanthrenequinone and 1,2-naphthoquinone. Current particle-phase quinone measurements agree well with the few available previous results. Further research is needed concerning the gas-particle partitioning behavior of quinones in ambient and combustion source conditions. 相似文献
989.
Ivask A Suarez E Patel T Boren D Ji Z Holden P Telesca D Damoiseaux R Bradley KA Godwin H 《Environmental science & technology》2012,46(4):2398-2405
By exploiting a genome-wide collection of bacterial single-gene deletion mutants, we have studied the toxicological pathways of a 60-nm cationic (amino-functionalized) polystyrene nanomaterial (PS-NH(2)) in bacterial cells. The IC(50) of commercially available 60 nm PS-NH(2) was determined to be 158 μg/mL, the IC(5) is 108 μg/mL, and the IC(90) is 190 μg/mL for the parent E. coli strain of the gene deletion library. Over 4000 single nonessential gene deletion mutants of Escherichia coli were screened for the growth phenotype of each strain in the presence and absence of PS-NH(2). This revealed that genes clusters in the lipopolysaccharide biosynthetic pathway, outer membrane transport channels, ubiquinone biosynthetic pathways, flagellar movement, and DNA repair systems are all important to how this organism responds to cationic nanomaterials. These results, coupled with those from confirmatory assays described herein, suggest that the primary mechanisms of toxicity of the 60-nm PS-NH(2) nanomaterial in E. coli are destabilization of the outer membrane and production of reactive oxygen species. The methodology reported herein should prove generally useful for identifying pathways that are involved in how cells respond to a broad range of nanomaterials and for determining the mechanisms of cellular toxicity of different types of nanomaterials. 相似文献
990.
Holmes RW Anderson BS Phillips BM Hunt JW Crane DB Mekebri A Connor V 《Environmental science & technology》2008,42(18):7003-7009
A statewide investigation of urban creek sediment toxicity was conducted in California in recognition of increased incidences of toxicity linked to pyrethroid pesticides. The goals were to examine the spatial occurrence and magnitude of sediment toxicity in California urban creeks, and to examine the role of pyrethroids in toxic urban creek sediment samples. After a preliminary screening of 90 sites, 30 creeks were sampled in eight geographical regions. Sediment toxicity was assessed using 10 day bioassays with the resident amphipod Hyalella azteca. Bioassays were conducted at two test temperatures of 23 degrees C and at 15 degrees C to provide evidence of the cause of toxicity, and to more accurately reflect ambient environmental temperatures. Twenty-five of 30 samples were toxic when tested at 23 degrees C, and all 30 samples were toxic when tested at 15 degrees C. The magnitude of toxicity increased in samples tested at 15 degrees C suggesting the influence of pyrethroids, which are more toxic at colder temperatures. Pyrethroids were present in all sediment samples and were the only compounds detected at concentrations toxic to H. azteca. Bifenthrin was the pyrethroid of greatest toxicological concern, occurring in all 30 samples at concentrations up to 219 ng/g. Pyrethroid contamination of urban creeks was most severe in the Los Angeles, Central Valley, and San Diego regions, respectively. However, pyrethroids were also linked to urban creek aquatic toxicity in all regions sampled, including the less urbanized areas of the North Coast and Lake Tahoe. 相似文献