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This research investigated the intakes of six intense sweeteners: acesulfame-K (E950), aspartame (E951), cyclamate (E952), saccharin (E954), sucralose (E955), and steviol glycosides (E960) in the diets of Irish adults, using data from the National Adult Nutrition Survey. A food label survey that included products currently available on the Irish market supplemented the analysis. Sweetener intakes were investigated using three different exposure scenarios; beginning with a crude assessment which assumed that all foods permitted to contain the additives of interest always did contain them, and at their maximum permitted level (Tier 1). Refined assessments estimated intakes of the six sweeteners using food consumption data up to brand level with additive occurrence data from a survey of products currently available on the Irish market (Tier 2) and sweetener concentration data (Tier 3). Results of all exposure assessment scenarios demonstrate that intakes of each of the sweeteners of interest by the total population were below the relevant ADI level (mg kg?1 bodyweight?1), even by high consumers (P99). The three sweeteners consumed in highest amounts were acesulfame-k, aspartame, and sucralose. The main sources of these sweeteners in the diet were ‘cider and perry’, ‘energy reduced and no added sugar (ER and NAS) carbonated flavoured drinks’, ‘table-top sweeteners’, ‘dairy products’, ‘solid food supplements’, and ‘sauces’. Intakes of the six intense sweeteners are currently not a concern among Irish adults. However, exposure to these chemicals should be monitored on a regular basis due to evolving market and consumption patterns.  相似文献   
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European consumers, in general, have negative attitudes towards the use of gene technology in food production. The objective of this study was to examine whether taste and health benefits influence the acceptability of genetically modified (gm) products when they are presented as real product alternatives. Consumers in Denmark, Finland, Norway and Sweden (n=738) assessed two cheeses: one was labelled as genetically modified (preferred in an earlier product test) and the other as conventional (neutral in an earlier product test). A smaller control group received two cheeses with blind codes. Labelling decreased consumers' intentions to buy the originally preferred gm-labelled cheese, but still the intentions were at the same level with the conventionally labelled option. Participants chose two gm cheeses out of five possible when given the option to take cheese home after tasting. Intentions to buy gm cheese could best be explained by respondents' attitudes towards gene technology and perceived taste benefits. General health interest was also a reinforcer of intentions for gm cheese with reduced fat content.  相似文献   
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Determination of trimethylamine in milk using an MS based electronic Nose   总被引:2,自引:0,他引:2  
A simple, rapid, reliable and highly automated analytical method has been developed to determine trimethylamine (TMA) in milk using an MS based electronic nose (SMart Nose). A set of Swedish milk samples with and without naturally occurring TMA was used to compare this new method with sensory analysis and dynamic headspace (DHS) gas chromatography with flame ionisation detection (GC-FID). The results show good agreement between these three analytical methods. A lower detection limit (0.5 mg kg-1) and better repeatability were achieved with this new method compared to both sensory and DHS GC-FID analyses (1-2 mg kg-1). The user-friendly multivariate analysis software provided with the SMart Nose system was used for TMA determination via a numerical PCA. Using Excel, peak intensity, correlated with TMA concentration via a second order equation, gave similar results. Thus, this is an up to date method of choice for the quantitative determination of TMA in milk. It is also able to give further qualitative information on the milk analysed using the PCA analysis supplied with this equipment.  相似文献   
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A study was conducted in 2009 to identify risk factors of Campylobacter spp. transmission from the digestive tract to the carcasses of standard broilers (slaughter age: 37 day, carcass weight: 1.3 kg on average). Counts of Campylobacter were performed on pools of 10 ceca and 10 neck-skins from 108 Campylobacter ceca-positive batches in three slaughterhouses. Technical and health data also was collected on the broilers: age, size, carcass weight (mean and standard deviation), condemnation rate, mortality rate and nature of treatment during the rearing period.Cecal counts varied from 4.8 to 10.2 log10 cfu/g. In seventeen batches (15.7%), the skin count was below the detection limit. In the 91 batches with positive neck-skin test results, the counts varied from 2.0 to 5.2 log10 cfu/g. Standard deviation of carcass weight, condemnation rate, slaughter rate and cecal count were significantly lower and growth rate higher in the 17 batches where neck-skin results were not detected positive. Multivariate analysis showed that batches with higher standard deviation of carcass weight were 5 to 9 fold more at risk of having detectable carcass contamination. Among the 91 positive neck-skin batches, only slaughter rate and cecal counts were found to have a significant but limited effect on the level of neck-skin contamination. As far as body weight homogeneity may be affected by disease, better health control can contribute to a reduction of the contamination of the broiler carcasses in Campylobacter carrier batches.  相似文献   
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Spices are parts of plants that due to their properties are used as colorants, preservatives, or medicine. The uses of spices have been known since long time, and the interest in the potential of spices is remarkable due to the chemical compounds contained in spices, such as phenylpropanoids, terpenes, flavonoids, and anthocyanins. Spices, such as cumin (cuminaldehyde), clove (eugenol), and cinnamon (cinnamaldehyde) among others, are known and studied for their antimicrobial and antioxidant properties due to their main chemical compounds. These spices have the potential to be used as preservatives in many foods namely in processed meat to replace chemical preservatives. Main chemical compounds in spices also confer other properties providing a variety of applications to spices, such as insecticidal, medicines, colorants, and natural flavoring. Spices provide beneficial effects, such as antioxidant activity levels that are comparable to regular chemical antioxidants used so they can be used as a natural alternative to synthetic preservatives. In this review, the main characteristics of spices will be described as well as their chemical properties, different applications of these spices, and the advantages and disadvantages of their use.  相似文献   
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Determination of biotin content in 10 fish‐meals produced from different species was performed by a microbiological assay using Lactobacillus plantarum as test organism. The contents of biotin in the fish‐meal samples ranged between 0.36 and 0.80 mg kg−1. Most of the fish‐meals contained approximately 0.4 mg biotin kg−1. The highest value was found in meal processed from sand eel (Ammodytes marinus). The precision of the assay showed a 2.7% relative standard deviation. Recovery using addition of biotin to the fish‐meal ranged between 93 and 95%. Testing of extraction procedure suggested that hydrolysis in 1.5 M H2SO4 at 121 °C for 3 h is sufficient for biotin to be liberated from proteins and amino acids. © 1999 Society of Chemical Industry  相似文献   
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