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Many vegetarians report that meat is unpleasant, but little else is known about their affective responses to meat and non-meat foods. Here we explored affective responses to food images in vegetarians and omnivores and tested the hypothesis that vegetarians have global differences in affective processing (e.g., increased disgust sensitivity). We presented pictures of different food items and recorded participants’ affective experience while we recorded peripheral physiology. We found that vegetarians’ self-reported experience of meat meal images was less pleasant than omnivores’, but that other food images were equally pleasant across the two groups. Moreover, vegetarians and omnivores had strikingly similar physiological responses to all food images – including meat meals. We interpret these results from a psychological constructionist perspective, which posits that individuals conceptualize changes in their bodily states in ways that match their beliefs, such that increased sympathetic nervous system activity may be conceptualized as an experience of excitement about a delicious meat meal for omnivores but as an experience of displeasure for a vegetarian who believes meat is cruel, wasteful, impure, or unhealthy. This interpretation is consistent with emerging neuroscience evidence that the brain constructs experience by predicting and making meaning of internal sensations based on past experience and knowledge.  相似文献   

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The newly introduced and improved products offered customers more premium choices, that plus rapid economic growth and rising demand for high quality and nutritional products among customers, stimulated strong growth in the Mengniu Dairy' s UHT milk products. Building on its existing products, the Group has strived for breakthroughs and it lately launched Deluxe Organic Milk, its first organic milk product.  相似文献   

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Texture analysis and modeling are important techniques in food and postharvest research and industrial practice. A wide range of methods have been used to evaluate instrumental results, which provide time-series data of product deformation, thereby allowing a wide range of texture attributes to be calculated from force–time or force–displacement data. Several indices of texture such as the firmness index, crunchiness index and texture index based on “vibration energy density” have been reported, but these are not widely used to quantify food texture. Some modeling and statistical approaches have been adopted to analyze food texture data, including chemical reaction kinetics and the Michaelis–Menton type decay function, mechanistic autocatalytic models based on logistic equation, and the finite element method. However, increasing demand for comprehensive approaches to texture profile analysis, generalized texture indices and fundamental texture models still remain challenges in the food research and industry.  相似文献   

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Exposure of individuals to natural environments, such as forests and coastlines, can promote stress reduction and assist in mental recovery following intensive cognitive activities. Settings as simple as hospital window views onto garden-like scenes can also be influential in reducing patients' postoperative recovery periods and analgesic requirements. This paper reviews the evidence supporting the exploitation of these restorative natural environments in future healthcare strategies. The paper also describes early research addressing the development of multisensory, computer-generated restorative environments for the benefit of patients with a variety of psychologically related conditions (including depression, attention deficit disorder, pain, and sleep deficit), who may be unable to access and experience real natural environments, such as those in hospices, military rehabilitation centers, and long-term care facilities. The Table of Contents art is a virtual reconstruction of Wembury Bay, in the southwest of the UK, based on imported Digital Terrain Elevation Data (DTED) to provide the topography and a high-resolution aerial image to provide a template for the location of 3D building and vegetation models, rock features, and pathways. The 3D environment is rendered using the Unity 3 Game Development Tool and includes spatial sound effects (waves, wind, birdsong, etc.), physics-based features (such as early morning sea mist), time-of-day cycles, and real-time weather changes. The Village Church of St. Werburgh can also be seen in this image.  相似文献   

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Trace elements, most notably aluminium and strontium, have been noted for their role in the development of secondary bone disorders in haemodialysis patients. Due to the large dosages of calcium required for the maintenance of dialysis patients, this study investigated whether the source of calcium chosen for supplementation, including the form of administration (i.e. chewable forms or capsules), has an influence on the total amount of strontium and aluminium ingested daily. A convenience sample of various calcium supplement tablets and antacids was acquired, and strontium and aluminium quantification was performed by wavelength-dispersive X-ray fluorescence spectrometry. The use of readily available oyster shell-based calcium was found potentially to increase the total amount of ingested strontium substantially with concentrations reaching (2.26 ± 0.05) (mg Sr)·(g Ca)?1, while the use of antacids or chewable supplements was found to contain concentrations reaching as high as (1.2 ± 0.3) (mg Al)·(g Ca)?1 in the supplements analysed within this work. It is recommended that the choice of calcium supplement prescribed to individuals undergoing haemodialysis be closely regulated and noted as a possible factor in the prevalence of bone disorders reported in these patients.  相似文献   

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The emerging field of nanotechnology is concerned with the ability to control structures at the molecular level and create new,complexstructures with fundamentally new properties and functions.Such capability has broad applicability to virtually every one of technology thataffects our lives, including changes in our use of natural resources,in the practice of agriculture and in food sciences.The National NanotechnologyInitiative in the United States expects to invest $ 604 million in 2002,to…  相似文献   

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JZ Zhong  W Liu  CM Liu  QH Wang  T Li  ZC Tu  SJ Luo  XF Cai  YJ Xu 《Journal of dairy science》2012,95(8):4237-4245
Our previous research indicated that dynamic high-pressure microfluidization (DHPM) had a significant effect on the antigenicity of β-lactoglobulin (β-LG). In this study, aggregation and conformational changes subjected to DHPM (0.1-160 MPa) were investigated in relation to antigenicity. When DHPM pressure increased from 0.1 to 80 MPa, disaggregation of β-LG samples and partial unfolding of the molecule were accompanied by an increase in β-LG antigenicity, which was reflected in the decrease of particle size, increase of free sulfhydryl (SH) contents and β-strands contents, and slight exposure of aromatic amino acid residues. At pressures above 80 MPa, the reaggregation of β-LG may contribute to the decrease in antigenicity, which was reflected by an increase in particle size, the formation of aggregates, a decrease of in SH and β-strands contents, and slight changes in aromatic amino acid residues. Aggregation and conformational changes of β-LG under DHPM was related to its antigenicity.  相似文献   

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The acrylamide levels in commercial and homemade Caribbean foods were determined by pre-derivatisation of acrylamide to 2-bromopropenamide and analysed by gas chromatography with mass spectrometric (GC/MS) detection. Over 100 Caribbean food samples were analysed for the presence of acrylamide. These samples include: biscuits, breakfast cereals, banana chips and home-prepared foods: breadfruit; Artocarpus altilis, banana fritters, and dumplings. The limit of detection (LOD) for the GC/MS method was found to be dependent on the type of column used for the GC/MS analysis. The DB-1701 and the DB-VRX columns gave LODs of 20 and 4 μg/kg, respectively. Acrylamide has not been found in raw foods or foods which have been cooked by boiling. Its content in all other foods had concentrations in the range, 65–3640 μg/kg. The relationship between acrylamide levels and precursor concentration as well as the health implications of our findings are discussed.  相似文献   

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Enteric viruses, particularly human Noroviruses (NoV) and hepatitis A virus (HAV), are key food-borne pathogens. The attachment of these pathogens to foodstuff and food-contact surfaces is an important mechanism in the human contamination process. Studies were done to investigate the nature of the physicochemical forces, such as hydrophobic and electrostatic ones, involved in the interaction virus/matrix but, at this day, only few data are available concerning surface properties of viruses and prediction of the adhesion capacity of one specific virus onto matrices is still very difficult. The purpose of this study was to propose a reference system, including a representative virus surrogate, able to predict as close as possible behaviour of pathogenic viruses in term of adhesion on inert (stainless steel and polypropylene) and food surfaces (lettuce leaves, strawberries and raspberries). The adhesion of human pathogenic enteric viruses, cultivable strain of HAV and non-cultivable strains of human NoV (genogroups I and II), have been quantified and compared to these of human enteric viruses surrogates, included the MNV-1 and three F-specific RNA bacteriophages (MS2, GA and Qβ). A standardized approach was developed to assess and quantify viral adhesion on tested matrices after a contact time with each virus using real-time RT-PCR. Methods used for virus recovery were in accordance with the CEN recommendations, including a bovine Enterovirus type 1 as control to monitor the efficiency of the extraction process and amplification procedure from directly extracted or eluted samples. The adhesion of human pathogenic viruses, ranging from 0.1 to 2%, could be comparable for all matrices studied, except for NoV GII on soft fruits. Adhesion percentages obtained for the studied surrogate virus and phages were shown to be comparable to those of HAV and NoV on inert and lettuce surfaces. The MNV-1 appeared as the best candidate to simulate adhesion phenomena of all human pathogenic enteric viruses on all studied surfaces, while MS2 and GA bacteriophages could be a good alternative as model of viral adhesion on inert and lettuce surfaces. These results will be usable to design relevant experimental systems integrating adhesion behaviour of enteric viruses in the assessment of the efficiency of a technological or hygienic industrial process.  相似文献   

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Foods containing bioactive components are receiving increasing attention due to their functionality in disease prevention and treatment. Soybean products contain a plethora of bioactive phytochemicals such as isoflavones, saponins, phytic acids, phytosterols, trypsin inhibitors, and peptides. Research has implicated soybean phytochemicals as functioning in cholesterol reduction, cardiovascular disease prevention, diabetic symptoms prevention, bone loss prevention, and cancer prevention. However, some bioactive compounds in soybean are reported to have some adverse effects to health also. Nevertheless, the benefits of soybean bioactive components exceed by far their potential adverse effects. The main objective of this article is to discuss the different soybean bioactive components and their implications to human health.  相似文献   

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An overview is given on the manufacture of the different types of tea along with the most important phenolics present in tea and methods of analysis. Compositional data are presented for green, white and black teas. A differentiation of green and black tea by using the ratio between total phenolics and sum of the major catechins seems to be feasible. For white tea there is no general accepted definition. Possible approaches are geographic origin, the botanical variety and the manufacture or the appearance. The differentiation between green and white teas by the ratio mentioned above is not possible. An erratum to this article is available at .  相似文献   

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Mycobacterium paratuberculosis, an acid-fast bacillus that causes enteritis in ruminants, has been suggested as an etiological agent of Crohn's disease in humans. The mode of transmission is unclear; however, some evidence suggests that humans may become infected via contaminated milk. Currently, it is not known whether commercial pasteurization effectively kills M. paratuberculosis in contaminated raw milk. Using a laboratory-scale pasteurizer unit designed to simulate the high-temperature, short-time method (72 degrees C, 15 sec) currently used by commercial dairies, we previously demonstrated that treatment of raw milk inoculated with 10(4) to 10(6) cfu of M. paratuberculosis/ml reduced numbers to an undetectable level. However, M. paratuberculosis is an intracellular pathogen that resides within the macrophages of the host and evades destruction. We subsequently performed further experiments examining heat treatment of milk inoculated with mammary gland macrophages containing ingested M. paratuberculosis. Heat treatment of these samples under high-temperature, short-time conditions demonstrated that the macrophage does not protect the organism because we were unable to recover any viable M. paratuberculosis from the samples. Conversely, other researchers have demonstrated that a residual population of M. paratuberculosis may survive heat treatment of milk. In addition, a recent news report stated that viable M. paratuberculosis organisms have been cultured from retail-ready milk in Ireland. A summary of past and current studies concerning this issue along with a discussion of methodologies used to recover M. paratuberculosis from experimentally inoculated milk will be presented in this paper.  相似文献   

15.
To offer useful information for milk pasteurization with radio-frequency or microwave heating, the dielectric properties (dielectric constant and dielectric loss factor) of raw cow’s milk and goat’s milk were determined over the frequency range of 10–4,500 MHz and temperature range of 25–75 °C by a vector network analyzer and an open-ended coaxial-line probe. The mathematical models describing the relationship between permittivities and temperature were built, and the power penetration depth was investigated. The results showed that both for cow’s milk and goat’s milk, the dielectric constants decreased with an increase of frequency, and the dielectric loss factor decreased with increasing frequency below 1,000 MHz and increased after that. The dielectric constants decreased with increasing temperature at a given frequency. For raw cow’s milk, the dielectric loss factor almost increased with temperature below about 800 MHz, and decreased with temperature above that. For raw goat’s milk, the loss factor decreased with temperature in whole investigated frequency range. Quadratic equations could be used to describe the relationship between permittivities and temperature at interested frequencies with coefficient of determination higher than 0.96. The penetration depth decreased with increasing frequency. Contrasted to frequency, temperature had less effect on penetration depth. Microwave heating at 915 MHz has great potential for raw cow’s milk pasteurization, while radio-frequency heating at 27.12 and 40.68 MHz and microwave heating at 915 MHz can be used for goat’s milk pasteurization.  相似文献   

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Relative concentrations of αS-casein (αS-CN) phosphorylation isoforms vary considerably among milk of individual cows. We aimed to explore to what extent genetic and other factors contribute to the variation in relative concentrations of αS-CN phosphorylation isoforms and the phosphorylation degree of αS-CN defined as the proportion of isoforms with higher degrees of phosphorylation. We also investigated the associations of genetic variants of milk proteins and casein haplotypes with relative concentrations of αS-CN phosphorylation isoforms and with the phosphorylation degree of αS-CN in French Montbéliarde cattle from the cheese production area of Franche-Comté. Detailed milk protein composition was determined by liquid chromatography coupled with electrospray ionization mass spectrometry from 531 test-day morning milk samples. Parity, lactation stage, and genetic variation of cows contributed to the phenotypic variation in relative concentrations of individual αS-CN phosphorylation isoforms and in the phosphorylation degree of αS-CN. As lactation progressed, we observed a significant increase for relative concentrations of αS-CN isoforms with higher degrees of phosphorylation (αS1-CN-9P, αS2-CN-13P, and αS2-CN-14P) as well as for the phosphorylation degree of both αS1-CN and αS2-CN. Furthermore, the β-CN I variant was associated with a greater proportion of isoforms with lower degrees of phosphorylation (αS1-CN-8P, αS2-CN-10P, and αS2-CN-11P); the β-CN B variant was associated with a greater proportion of isoforms with higher degrees of phosphorylation (αS1-CN-9P, αS2-CN-12P to αS2-CN-14P). The heritability estimates were low to moderate for relative concentrations of αS2-CN phosphorylation isoforms (0.07 to 0.32), high for relative concentrations of αS1-CN-8P (0.84) and αS1-CN-9P (0.56), and moderate for phosphorylation degrees of αS1-CN (0.37) and αS2-CN (0.23). Future studies investigating relations between the phosphorylation degree of αS-CN and technological properties of milk will be beneficial for the dairy industry.  相似文献   

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Genebanks conserve key resources for handling current and future challenges to food production and security. The role of genebanks has evolved from primarily serving plant breeders to include long-term biodiversity conservation and distribution to a wider user community. International policy frameworks stress the complementarity of ex situ and in situ conservation and management, but a dichotomy prevails in the public and scholarly agricultural development discourse. Here, we present a study of existing linkages between the two conservation and management approaches, their challenges and future options. First, we show that farmers, farmer organizations, and NGOs now comprise a considerable user group of genebank material, receiving at least 8% of the seed samples distributed from international genebanks in 2015, on par with the proportion distributed to the commercial seed sector. Second, we map and categorize approaches to introduce genebank material into farmers’ seed systems. Based on a survey, interviews and a literature review we categorize direct genebank-farmer linkages into six categories: (1) Reintroduction, (2) Emergency Seed Interventions, (3) Community Seed Banks, (4) Participatory Plant Breeding, (5) Variety Introduction, and (6) Integrative Seed System Approaches. We investigate the merits of these approaches as alternative and complementary pathways for enhancing farmers’ access to crop diversity. Finally, we discuss challenges related to scale, sustainability and legal frame conditions and point out opportunities to realize synergies to achieve the ultimate goal of the ex situ conservation agenda and the farmers’ rights agenda, namely to strengthen farmers’ access to suitable seeds.  相似文献   

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Efforts to manage the environmental risks of selenium (Se) in freshwater ecosystems have focused primarily on fish and birds, with invertebrates most often considered only as dietary sources of Se to higher trophic levels. Relatively little attention has been given to the risk of Se toxicity to invertebrates. Based on a review of 156 aqueous, dietary, or internal Se concentrations associated with toxic effects in 29 macroinvertebrate species, we found that water concentrations associated with acute lethality varied > 1000-fold among taxa, whereas toxic dietary concentrations varied approximately 100-fold and toxic internal concentrations varied about 30-fold. Sublethal effects occurred at approximately 10-fold lower concentrations than lethality. Sublethal effects occurred at 1-30 microg Se/g dry weight in invertebrate tissue, a range that encompasses proposed dietary thresholds for toxicity to fish and water birds, suggesting that Se may cause toxic effects in some invertebrate species at concentrations considered to be "safe" for the organisms consuming them.  相似文献   

20.
Several food additives are added in food for their preservation to maintain the freshness of food (antioxidants) or to slow down or stop the growth of microorganisms (preservative agents). Nitrites and nitrates are used as preservative agents in meat. Nitrites give a smoked taste, a pinkish color in the meat and protect the consumers against the risk of bacterial deterioration. Their addition is however very limited as, in high dose, it can have risks on human health and the environment. Nitrites may also combine with secondary or tertiary amines to form N-nitroso derivatives. Certain N-nitroso compounds have been shown to produce cancers in a wide range of laboratory animals. Thus, alternatives of nitrates and nitrites are the object of numerous research studies. Alternatives, such as the addition of vitamins, fruits, chemicals products, natural products containing nitrite or spices, which have similar properties of nitrites, are in evaluation. In fact, spices are considered to have several organoleptic and anti-microbial properties which would be interesting to study. Several spices and combinations of spices are being progressively evaluated. This review discusses the sources of nitrites and nitrates, their use as additives in food products, their physicochemical properties, their negatives effects and the use of alternatives of nitrites and nitrates in preserving meat products.  相似文献   

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