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1.
Omega-3 fatty acids are generally under-consumed in Western diets; a factor that may largely be attributed to low intake of oily fish. Although supplementation strategies offer one approach in terms of improving blood fatty acid levels, rates of compliance are generally low due to difficulties in swallowing capsules, or unfavorable aftertastes. Consequently, new approaches, including food-based strategies, may be an alternative approach to improving omega-3 status and the health of public sectors. This paper sets out to discuss and review how the use of novel food vehicle and delivery advancements may be used to improve omega-3 status, which may have wider benefits for public health and well-being.  相似文献   

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Several essential oils of medicinal plants possess proven antimicrobial activity and are suitable for applications on the food industry. The oil from Cymbopogon citratus (lemongrass) has been reported to have a wide range of biological activities. However, there are few controlled studies confirming its antimicrobial activity. The aim of our study was to assess the antimicrobial potential of lemongrass oil against a wide spectrum of food spoilage and pathogenic bacteria and yeast in liquid and vapour phase. The chemical composition of the oil was analyzed by gas chromatography; 14 components were identified and geranial (28.93 %), neral (24.30 %) and myrcene (23.92 %) were the most abundant constituents. Lemongrass oil showed potent antimicrobial activity against Gram positive bacteria and exhibited the strongest antifungal effect against Candida albicans and C. parapsilosis. Minimum inhibitory concentration varied from 0.019 to 1.25 mg mL?1 for Gram positive bacteria and yeasts, indicating Staphylococcus aureus, S. epidermidis and C. albicans as the most susceptible strains. Moreover, the diameter of inhibition zone (DIZ) increased with increasing essential oil (EO) volume. Considerably superior antimicrobial activity was observed in the vapour phase. The DIZ resulting from the exposure to EO vapour was significantly larger than that from the same volume in the liquid phase. The DIZ varied from 22 to 90 mm for Candida strains. There is growing evidence that EO in vapour phase are effective antimicrobial systems and that they do have advantages over the use of oil in liquid phase. Our results imply that lemongrass oil could be useful for the development of novel types of natural preservatives for food control.  相似文献   

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Transgenic and cloned animal production for various purposes has been increasing rapidly in recent times. While the actual impact of these animals in the food chain is unknown, the significance of tracking and monitoring measures to curb accidental and or deliberate release has been discussed. Religious perspectives from different faiths and traditions have been presented. Although the concept of substantial equivalence satisfies the technical and nutritional requirements of these products when assessed against comparators, public opinion and religious concerns should also be considered by the regulators while developing policy regulations. In conclusion, measures to prevent real or perceived risks of transgenic and cloned animals in food production require global coordinated action. It is worthwhile to consider establishing effective tracking systems and analytical procedures as this will be a valuable tool if a global consensus is not reached on policy regulation. © 2015 Society of Chemical Industry  相似文献   

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There is increasing evidence for a viable but non-culturable (VBNC) state in microbes, particularly in the stressing environment presented by modern foods with their varied pre-treatment and packaging strategies. This is a cause for concern because of evidence that microbial pathogens in such a state may retain their capacity to cause infections after ingestion by the consumer despite their inability to grow under the conditions employed in procedures for determining their presence in foods. Heavily stressed pathogenic species of bacteria in a VBNC or not immediately culturable state are potentially dangerous public health problems, particularly as stressed cells may be more virulent than well-fed bacteria. In this viewpoint article, I wish to focus on possible procedures for detecting such organisms and assessing their physiological state.  相似文献   

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Although high concentrations of zinc and manganese were found in mandibles of insect larvae that bore into seeds, these metals were not detected in mandibles of insect larvae that attack previously damaged seeds. Metals were present in the larval mandibles of a lepidopteran, the Angoumois grain moth (Sitotroga cerealella), and eight coleopterans, the lesser grain borer (Rhyzopertha dominica), cigarette beetle (Lasioderma serricorne), drugstore beetle (Stegobium paniceum), spider beetle (Gibbium aequinoctiale), warehouse beetle (Trogoderma variabile), cadelle (Tenebroides mauritanicus), larger black flour beetle (Cynaeus angustus), and cowpea weevil (Callosobruchus maculatus). Larvae of these species can chew into seeds. Larvae of six other coleopterans, the varied carpet beetle (Anthrenus verbasci), sawtoothed grain beetle (Oryzaephilus surinamensis), rusty grain beetle (Cryptolestes ferrugineus), red flour beetle (Tribolium castaneum), longheaded flour beetle (Latheticus oryzae), and granary weevil (Sitophilus granarius) have little if any ability to chew into seeds, and did not have metal in their mandibles. Larvae of the granary weevil hatch and feed within seeds that were penetrated previously during egg deposition by adults. However, newly hatched larvae of the cowpea weevil and the Angoumois grain moth have to bore through the seed coat before they begin feeding, and they have mandibles with high concentrations of zinc. These data support the hypothesis that deposition of zinc and/or manganese in larval mandibles enhances the larva's ability to penetrate seeds.  相似文献   

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A range of starch granule populations varying in size and shape characteristics was isolated from greengram (CG) and Bengalgram (BG) flours. All the starches were non-ionic and exhibited single state swelling with hihg solubility in water, but extensive solubility in DMSO. The starch content of the different populations varied from 40-80%, whereas the protein and lipid contents of the isolates I to III were lower than those of the isolate IV. Their amylose content ranged between 32-46%. Brabender viscograms indicated low values for peak and setback viscosities in the case of BG starch compared to GG starch. Fatty acid analysis of the lipid fractions indicated predominance of palmitic acid. GG starch exhibited a slightly higher in vitro digestibility than BG starch.  相似文献   

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The variation among bioconcentration factors (BCFs) available in the literature is commonly ascribed to experimental parameters and metabolic capacity. Though bioconcentration is generally considered to be governed by partitioning processes and therefore to depend on the composition of the partition phases, the effect of lipid composition on BCFs measured for hydrophobic organic chemicals has largely escaped attention. The reason may be that the effect cannot easily be studied separately in a conventional BCF test setup and that any subtle effects will often be obscured by the variation normally observed when working with living organisms. In the present study, this variation was circumvented by substituting biota with biological homogenates, which allowed measuring chemical partitioning in a fashion that has proved successful for many other environmental matrixes (e.g., sediments, soils, carbonaceous materials). The appropriateness of using a homogenate as a representation of the organism from which it was derived was demonstrated by a good agreement between homogenate-water partition coefficients (or necroconcentration factors; NCFs) and actual BCFs for PCBs and aquatic worms. Subsequent experiments focused on the intra- and interspecies differences in lipid-normalized NCFs. Intraspecies variation was studied for aquatic worms and sticklebacks, which were acclimatized at different temperatures (5-24 °C), whereas interspecies variation was investigated by determining NCFs for eight different aquatic species. Although temperature-induced intraspecies differences were subtle (<0.16 log units), interspecies differences among lipid-normalized NCFs were as high as 0.9 log units, with homogenates of "simple" organisms showing a lower sorption capacity than those of the more "complex" species. These results suggest that the variation observed in the literature BCFs may partly be caused by differences in lipid composition and contest the usefulness of the common practice of applying generic BCFs in risk assessment of chemicals.  相似文献   

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BACKGROUND: Squid oil contains high concentration of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The purpose of this work was to optimize the process of separation by molecular distillation of ω‐3 fatty acid ethyl esters obtained from squid oil. The separation process was conducted in two stages in a laboratory‐scale molecular distiller. A mathematical model based on the mass transfer phenomena was developed. The Nelder‐Mead numerical method was used to optimize the model. RESULTS: The ω‐3 content in the output material of the stage II increased with the temperature of stage I (T1). The amount of distillated material in stage I increased and the distillated material in the stage II decreased with the increment of T1. That implied a decreasing of the ω‐3 recovery in the distillated material in the stage II. In addition, the ω‐3 recovery increased with the temperature of stage II (T2), but the temperatures should be less than 140 °C to avoid chemical changes. The optimization results showed an optimal process at T1 = 120.5 °C and T2 = 140 °C. CONCLUSION: The theoretical model and the optimization give decision criteria about the operative conditions for reaching the highest yield during molecular distillation of ω‐3 fatty acid ethyl esters. Copyright © 2011 Society of Chemical Industry  相似文献   

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To understand effects of milling, scented rice ‘Cheonjihyang-1-se’ was milled from 10 to 140 s and changes in volatiles, phytonutrients, and fatty acids were evaluated. Among 43 identified odor-active compounds, four volatiles, including hexan-3-one, exhibited decreases of up to 78%, while four others including (E)-non-2-enal, increased following milling. Levels of 2-acetyl-1-pyrroline, the most distinctive popcorn-flavoring compound in scented rice, were not affected by the degree of milling (DM). Partial least squares discriminant analyses of volatiles were able to differentiate white rice according to the DM. Benzene and 2-pentylfuran showed the highest variable importance in projection scores, which could be applied in estimating the DM of rice. Milling significantly decreased tocopherols, tocotrienols, squalene, phytosterols contents and oleic acid composition, while palmitic acid composition was increased. These results suggest milling-dependent variations in phytonutrient levels and lipid composition, as well as changes in aroma and subsequent market quality, in ‘Cheonjihyang-1-se’ rice.  相似文献   

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Studies performed in 2001 and 2003 surveyed the release of carcinogenic nitrosamines and nitrosatable substances from rubber toy balloons by extraction with artificial saliva and gas chromatography-thermal energy analysis (GC-TEA). 81% of the 16 in 2001 sampled balloons and 93% of the 14 in 2003 sampled balloons released nitrosamines above the recommended level in Germany of 10 mug per kg material. Furthermore, 32 rubber condom samples collected in 2004 from the German market were surveyed for nitrosamines by determining the amount migrating into an artificial sweat test solution. The levels released from condoms varied from < 10 to 660 mug per kg material (i. e., up to 1.4 mug nitrosamines per condom). In a model calculation, not considering the differences that may exist in the resorption rate, we have calculated that the exposure from condoms may exceed the exposure from food 1.5-3 fold. To our knowledge so far no legal binding legislation exists worldwide concerning nitrosamine migration from toy balloons or condoms.  相似文献   

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A method is described to lower the detection limit for mineral oil saturated hydrocarbons (MOSH) in foods as compared to the on-line HPLC–LC–GC–FID method described previously: samples are preseparated (enriched) by conventional liquid chromatography on activated silica gel and activated aluminum oxide. The silica gel retains up to 1 g of fat or oil, the aluminum oxide up to 2 mg n-alkanes of at least 24 carbon atoms, i.e. plant paraffins which may severely hinder the analysis of the mineral paraffins. The efficacy of the method is shown for an apple and sunflower oil. Oils extracted from manually harvested seeds grown in fields or gardens contained between 0.14 and 0.77 mg/kg MOSH. In the oils from seeds sampled in an oil mill, this value was increased to 3.3–9.3 mg/kg, indicating a contamination during harvest, transport and/or storage. Concentrations in commercial refined sunflower oils ranged between 2.7 and 32 mg/kg, averaging 11.2 mg/kg. Since deodorization removes a substantial part of the MOSH, this suggests a further contamination in the oil mill. The contamination affected all samples at a similar level, indicating that it occurs systematically by the presently used technology.  相似文献   

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BACKGROUND: A number of retail shops in Copenhagen sell fresh cassava roots. Cassava roots contain the toxic cyanogenic glucoside linamarin. A survey was made of the shop characteristics, origin of the roots, buyers, shop owner's knowledge of toxicity levels, and actual toxicity levels. RESULTS: Shops selling fresh cassava were shown mostly to be owned by persons originating in the Middle East or Afghanistan, buyers were found to predominantly be of African origin, and sellers' knowledge concerning the potential toxicity was found to be very restricted. Seventy‐six per cent of the roots purchased had a total cyanogenic potentials (CNp) above the 50 mg HCN equivalents kg?1 dry weight (d.w.) proposed as acceptable by an EU working group. Two of 25 roots purchased had CNp higher than 340 mg HCN eq. kg?1 d.w. CONCLUSION: The EU has previously made risk assessments concerning cassava and cyanogenic compounds. In the light of the conclusions drawn, the EU needs to make decisions about how to deal with the regulation and control of fresh cassava roots imported to the European food market. Also cassava root products and cassava leaves should be considered. Copyright © 2009 Society of Chemical Industry  相似文献   

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