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21.
Francielo Vendruscolo 《国际能源研究杂志》2015,39(3):293-302
Hydrogen is a clean energy carrier with great potential to be an alternative fuel. Anaerobic hydrogen fermentation seems to be more favorable, since hydrogen is yielded at high rates and various organic waste and wastewater enriched with carbohydrates as substrate result in low cost for hydrogen production. Abundant biomass from various industries could be a source for biohydrogen production where combination of waste treatment and energy production would be an advantage. Carbohydrate‐rich nitrogen‐deficient solid wastes such as starch residues can be used for hydrogen production by using suitable bioprocess technologies. Alternatively, converting biomass into gaseous fuels, such as biohydrogen, is possibly the most efficient way to use these agroindustrial residues. This review summarizes the potential of starch agroindustrial residues as a substrate for biohydrogen production. Types of potential starch agroindustrial residues, recent developments and bio‐processing conditions for biohydrogen production will be discussed. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
22.
Maria Grazia Basanisi Gianfranco La Bella Gaia Nobili Rosa Coppola Annita Maria Damato Maria Assunta Cafiero Giovanna La Salandra 《International Journal of Food Science & Technology》2020,55(3):1145-1150
The authenticity and traceability of meat products are issues of primary importance to ensure food safety. Unfortunately, food adulteration (e.g. the addition of inexpensive cuts to minced meat products) and mislabelling (e.g. the inclusion of meat from species other than those declared) happens frequently worldwide. The aim of this study was to apply a droplet digital PCR assay for the detection and quantification (copies μL−1) of the beef, pork, horse, sheep, chicken and turkey in meat products. The analysis conducted on commercial meat showed the presence of traces of DNA from other animal species than those declared. We show that the method is highly sensitive, specific and accurate (accuracy = 100%). This method could be adopted by competent food safety authorities to verify compliance with the labelling of meat products and to ensure quality and safety throughout the meat supply chain, from primary production to consumption. 相似文献
23.
纳米纤维素作为一种性能优越的可再生纳米材料,应用前景极为广阔。然而,由于纳米纤维素结构上富含羟基,使其具有极强的亲水性,严重影响了纳米纤维素的疏水性能,并且在一定程度上限制了其在复合材料领域的应用。综述了纳米纤维素疏水改性的研究进展,从物理吸附、表面化学修饰(甲硅烷化、烷酰化、酯化等)、聚合物接枝共聚3个方面简述了目前应用较为广泛的疏水化改性方法,并对疏水纳米纤维素在包装材料、造纸、水净化等方面的应用现状进行了总结。最后对疏水改性纳米纤维素的未来发展进行了展望,旨在为疏水纳米纤维素的研究和应用提供参考。 相似文献
24.
《Food Control》2015
This study aimed to estimate the extent and level of Salmonella contamination of aquatic food products in China, and to determine serotype, virulotype, and the antimicrobial resistance profiles of recovered Salmonella isolates. Out of 554 samples collected from July 2011 to May 2014, 86 (15.5%) tested positive for Salmonella. The highest contamination rate occurred in oysters (23.1%, 6/26), followed by freshwater fish (18.6%, 43/231), shrimp (13.0%, 13/100), and saltwater fish (12.2%, 24/197). The contamination levels generally corresponded to a most probable number (MPN)/g of 0.3–10, although one sample exceeded 110 MPN/g. Among the 103 isolates, S. Typhimurium, S. Wandsworth, S. Thompson, and S. Derby were the most prevalent serovars. Sixty-eight isolates (66.0%) were resistant to at least one antimicrobial, and 35 (34.0%) were resistant to more than three. High rates of resistance were observed for tetracycline (35.9%), ampicillin (28.2%), nalidixic acid (26.2%), trimethoprim-sulfamethoxazole (25.2%), chloramphenicol (20.4%) and streptomycin (18.4%). Of note, S. Thompson isolates exhibited resistance to multiple extended-spectrum cephalosporins, ciprofloxacin, and other antimicrobials. PCR analysis of 15 virulence genes showed that ssaQ, mgtC, siiD, sopB, and bcfC were present in all 103 isolates, whereas the remaining loci were variably distributed. S. Typhimurium, S. Enteritidis, and S. Weltevreden isolates exhibited a wider range of pathogenicity determinants compared with the other strains. Our study provides a comprehensive surveillance on prevalence of Salmonella in aquatic food products from China and indicates its potential risk to public health. These data are valuable for epidemiological studies, risk management, and public health strategies. 相似文献
25.
ABSTRACTThis paper proposes the multiple-hypotheses image segmentation and feed-forward neural network classifier for food recognition to improve the performance. Initially, the food or meal image is given as input. Then, the segmentation is applied to identify the regions, where a particular food item is located using salient region detection, multi-scale segmentation, and fast rejection. Then, the features of every food item are extracted by the global feature and local feature extraction. After the features are obtained, the classification is performed for each segmented region using a feed-forward neural network model. Finally, the calorie value is computed with the aid of (i) food volume and (ii) calorie and nutrition measure based on mass value. The experimental results and performance evaluation are validated. The outcome of the proposed method attains 0.947 for Macro Average Accuracy (MAA) and 0.959 for Standard Accuracy (SA), which provides better classification performance. 相似文献
26.
《Food Control》2015
A telephone survey was carried out on 13,486 randomly selected households located in the Abruzzo region (central Italy). Three questionnaires were specifically designed in relation to three different groups of foods (Meat and meat products, Fishery products, Fruit and vegetables). Questions were mainly focused on the amount and number of purchases, type of retailer, and home food handling practices with respect to the week prior to the interview. Data were classified according to a multilingual thesaurus system (LanguaL). Results allowed to estimate domestic purchases (in kg) per capita for different food categories. The category “Red meat/Cattle” accounted for a large part of purchases in the “meat and meat products” group (10.9 kg per capita/year; 32.2% of purchases in the group) while the category “Fish or related organism/Fish” was the most purchased in the “fishery products” group (6.9 kg per capita/year; 63.3%). The aggregation of more detailed characteristics enabled the identification of popular categories of foods, such as “Red meat/Cattle/Divided into pieces” (25% of the “meat and meat products” group). Significant differences (p < 0.05) were found between the four different provinces (L'Aquila, Chieti, Pescara and Teramo) with respect to “Poultry/Chicken” and “Red meat/Cattle” categories. Householders were also asked about post-purchase food handling practices that might be hazardous to food safety. More than 20% of those surveyed stated that they thawed frozen meat at room temperature. The degree of doneness after cooking of different food categories was generally high: over 90% of products purchased in the majority of meat and fish categories were properly cooked. However a noticeable proportion of householders (about 15%) reported medium or rare cooking of “Red meat/Cattle” and “Red meat/Swine”. Differences (p < 0.05) were also found between consumers of different ages, with people over 65 years old being more prone to freeze meat and cook it thoroughly.The survey was carried out in a specific geographic area and on a statistically significant sample of households, thus allowing a collection of data on domestic habits relating to food purchases and home food handling practices. This information should be included in the framework of quantitative microbial risk assessment (QMRA) models as a measure of the actual exposure of consumers to pathogenic microorganism. The LanguaL system also proved to be a practical language-independent method useful not only to identify and describe food items but also to classify them according to specific food safety characteristics. 相似文献
27.
28.
This study was undertaken to develop a modified atmosphere package to control microbial growth in ready‐to‐eat (RTE) products stored at ambient temperature. Ethanol and/or limonene associated with modified atmosphere (CO2 : O2 : N2 = 30% : 5% : 65%) was used to inhibit the growth of total air‐borne microorganisms and Escherichia coli in RTE products stored at 25°C. The results indicated that 0.05% ethanol vapour in the headspace was effective to inhibit the growth of air‐borne microorganisms and E. coli at 25°C for 72 h in a model study, and the effectiveness was related to ethanol content. Both 73 ppm limonene and 0.05% ethanol vapour enhanced the bacteriostatic effect of modified atmosphere in RTE sushi roll products, and no off‐flavour was detected using this formulated gas; however, no significant inhibitory effect was observed for RTE cold noodle products. This study concludes that combinations of carbon dioxide, ethanol or limonene vapours are effective to inhibit microbial growth in RTE food at ambient temperature, and the outcome may be due to the hurdle effect. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
29.
The Industry Council for Development (ICD) is an Industry Non Governmental Organisation established in 1990; it aims to contribute to improving public health through partnership projects on food safety and nutrition. This paper presents ICD’s activities in the past years and explains the reasons why the food industry should have a vested interest in supporting training and education of health professionals in food safety. 相似文献
30.