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11.
《Food Control》2006,17(8):631-636
Recently, DNA-based techniques became very common for the detection of genetically modified organisms (GMOs) in food products. For rapid and easy detection of GMOs, polymerase chain reaction (PCR) screening methods, which amplify common transgenic elements, are applied in routine analysis. Incorporation of PCR and membrane method introduced in this study offer an alternative detection of GMOs. In this study, a total of 32 samples and three certified reference materials were tested for the existence of the 35S promoter of cauliflower mosaic virus (CaMV) and 5-enol-pyruvyl-shikimate-3-phosphate synthase (EPSPS) gene residues. Dot blot screening system introduced in this study can be routinely used as a semi-quantitative screening of GMOs. 相似文献
12.
《Journal of Visual Communication and Image Representation》2008,19(1):42-55
In visual cognition, illusions help elucidate certain intriguing latent perceptual functions of the human vision system, and their proper mathematical modeling and computational simulation are therefore deeply beneficial to both biological and computer vision. Inspired by existent prior works, the current paper proposes a first-order energy-based model for analyzing and simulating illusory contours. The lower complexity of the proposed model facilitates rigorous mathematical analysis on the detailed geometric structures of illusory contours. After being asymptotically approximated by classical active contours, the proposed model is then robustly computed using the celebrated level-set method of Osher and Sethian [S. Osher, J.A. Sethian, Fronts propagating with curvature-dependent speed: algorithms based on Hamilton–Jacobi formulations, J. Comput. Phys., 79 (12) (1988) 12–49] with a natural supervising scheme. Potential cognitive implications of the mathematical results are addressed, and generic computational examples are demonstrated and discussed. 相似文献
13.
《Food Control》2006,17(8):676-679
In this study, the presence of Listeria spp. was investigated in a total of 157 raw milk and dairy product samples sold in Antakya (Antioch). The prevalence of Listeria spp. in raw milk and Turkish white cheese samples was found to be 2.12% and 8.23%, respectively. Listeria monocytogenes was not isolated from raw milk and found in only two cheese samples (2.35%). No Listeria spp. were isolated in any of the butter and yoghurt samples. 相似文献
14.
《Food Control》2007,18(5):554-557
The incidence of Listeria spp. in the salt-water edible fish and in the environment of fish markets in Thessaloniki, Northern Greece was studied. One hundred and twenty raw/fresh fish bought at the fish markets of Thessaloniki (Northern Greece), were sampled and tested for presence of Listeria species using a two step enrichment procedure, followed by plating on two selective agars and subsequent biochemical identification of the isolates. Five fish samples were positive for Listeria spp. and in only one sample L. monocytogenes was detected. Also, 100 samples of knives, hands, boxes etc were sampled and 18 samples were positive for Listeria spp. and five for L. monocytogenes. L. innocua was more common being detected in four fish samples and 13 environmental samples. L. seeligeri was detected only in one environmental sample. Our findings indicate that only a few fish were contaminated with Listeria spp., while the level of contamination of the environment of fish markets was higher. 相似文献
15.
16.
《Construction and Building Materials》2005,19(2):117-126
The dumping of spent grains is going to be more difficult because of the increasing number of cattle. That means new ways of dumping must be developed.The goal of the work was to test the technical properties of bricks produced with spent grains added to increase porosity.The flexural strength of the fired samples remained at 8.5 MPa; the air-dried samples exhibited a small increase in flexural strength. The shrinkage and true density were almost identical, while the raw density, capacity for water absorption and open porosity showed minor differences.In the large-scale experiment no problems were observed during the production. The bricks produced with spent grains possessed a comparable or higher strength, a higher porosity and a reduced density after firing than those from a standard production clay. Because of the lower sintering temperatures the fired clay product was more strongly sintered, exhibiting both greater strength and higher porosity. 相似文献
17.
Raw and heat processed peanut flours were found to contain higher in vitro trypsin inhibitor activity and lectin content than similarly processed soy flour. When fed to weanling rats at a level of 10% protein, the response pattern in food consumption, growth, liver function, and serum chemistries was not consistent among or between the groups. It is concluded that the levels of antinutritional factors in legumes do not correlate with their overall biological impact in feeding studies with the rat. 相似文献
18.
《Innovative Food Science and Emerging Technologies》2007,8(1):73-83
Conjoint analytic surveys were administered to 225 potential consumers of foods processed by innovative and emerging food technologies in order to assess the factors contributing to their interest in using such products. Respondents included 1) a consumer panel of civilian lab employees, 2) shoppers in a mall in the northeastern U.S., and 3) U.S. military troops on training exercises. Respondents rated their interest in 49 different food product concepts that varied in food type, processing or production technology, costs, benefits, risks, endorsing agencies, and product information. Results showed that the relative importance of factors did not vary greatly among the consumer groups. Perceived risks associated with the technologies were the most important factors influencing interest in use. Among the emerging technologies assessed, irradiation and genetic modification resulted in the greatest negative effect on likely use, while high pressure processing produced the most positive effect. The term “cold preservation” had positive associations for all groups, but “minimally processed” had negative associations. Implications of the data for the marketing of foods processed by innovative and emerging technologies are discussed.Industrial relevanceThe food industry is currently interested in a variety of novel production and processing technologies that may result in economical and improved quality products. However, consumer attitudes toward and conceptions of these new technologies can greatly influence their success in the marketplace. The results of this study show that “perceived risks” of the technologies are the most important determinant of interest in their use by consumers. This and other data uncovered in this study suggest that industry must be vigilant in their knowledge of consumer attitudes toward these processes in order to avoid unexpected failure of these products upon market introduction. 相似文献
19.
《Food Control》2007,18(2):93-101
The antimicrobial properties of pure phenolic compounds and polyphenols of different wines against pathogens were investigated. It was observed that bacterial species exhibited different sensitivities towards the different concentrations of phenolic compounds. Escherichia coli was the most sensitive bacterium and Flavobacterium sp. was resistant against all phenolic compounds tested. All wine samples showed antimicrobial properties and the inhibition increased when the polyphenols concentration of wines increased. Clarified wines were inactive against all bacteria, indicating that polyphenolic compounds present in red wines, are responsible for the antimicrobial effects observed. The different concentrations of polyphenols in wines could have an important impact on consumers with the consequent increase in wine commercialization. 相似文献
20.
Male weanling rats were subjected to standard 28-day PER trials following the outline by the AOAC (1984) except that the diets contained 8.5% protein (N × 6.25) as one of six wheat-based breakfast cereals, white flour, whole wheat flour or casein. One of the cereals was an extrusion puffed product, three were flaked and toasted cereals and two were extruded cereals. Of the two extruded cereals, one was lightly toasted and the other was more heavily toasted. Relative PER (R-PER) was lowest for the puffed cereal (- 15.3) and highest for the extruded-lightly toasted cereal (69.9). R-PER for the flaked cereals ranged from 1.7 to 16.3; the other extruded cereal had a R-PER of 2.8 and each of the two flours had a R-PER of 42.9. 相似文献