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951.
Sushi is a traditional Japanese food, mostly consisting of rice and raw fish. Fish is considered a healthy food, but as with other animal products, consumption of raw muscle incurs potential health risks such as ingestion of pathogenic bacteria or parasites. In this study, 250 sushi samples were analyzed for their microbiological status and the prevalence of pathogenic bacteria. A comparison was made between frozen sushi from supermarkets and fresh sushi from sushi bars. Aerobic mesophilic bacteria counts differed for sushi from these two sources, with means of 2.7 log CFU/g for frozen sushi and 6.3 log CFU/g for fresh sushi. The prevalence of Escherichia coli and Staphylococcus aureus was higher in the fresh samples. Salmonella was found in four (1.6%) of the sushi samples, and Listeria monocytogenes was found in three (1.2%) of the samples. These results indicate that the microbiological quality of industrially processed sushi is higher than that of freshly prepared sushi. The quality of freshly prepared sushi strongly depends on the skills and habits of the preparation cooks, which may vary. 相似文献
952.
María Teresa Pretel María Serrano Asunción Amorós Felix Romojaro 《European Food Research and Technology》1999,209(2):130-134
Ethylene synthesis and metabolism were studied in apricot fruits (Prunus armeniaca L. cv. Búlida, under controlled atmosphere (CA) conditions (20% CO2 and 20% O2; 20% CO2 and 1% O2; 0.03% CO2 and 1% O2) and at a temperature of 2 °C. In control apricots stored outdoors in air containing 20% O2 and 0.03% CO2, the evolution of the physical and chemical parameters characteristic of ripening (loss of texture, decrease in acidity and
increase in soluble solids) was slow during the storage period. However, for apricots stored in CAs containing 1% O2 and 20% or 0.03% CO2, these parameters did not show significant changes during the storage period. Ethylene production was completely inhibited
in apricots stored in the three CAs, while control fruits showed a maximum ethylene level after 2 weeks of storage. This inhibition
was accompanied by lower levels of 1-aminocyclopropane-1-carboxylic acid, free and total, which were more pronounced in apricots
stored in the CAs containing 20% CO2. In apricots stored in the CAs containing 1% O2, the ethanol content increased after 1 week of storage, and this caused a smell and taste that made the fruits unsuitable
for consumption.
Received: 16 October 1998 相似文献
953.
Aspects of high hydrostatic pressure food processing: Perspectives on technology and food safety 总被引:1,自引:0,他引:1
Kemal Aganovic Christian Hertel Rudi. F. Vogel Reimar Johne Oliver Schlüter Uwe Schwarzenbolz Henry Jäger Thomas Holzhauser Johannes Bergmair Angelika Roth Robert Sevenich Niels Bandick Sabine E. Kulling Dietrich Knorr Karl-Heinz Engel Volker Heinz 《Comprehensive Reviews in Food Science and Food Safety》2021,20(4):3225-3266
The last two decades saw a steady increase of high hydrostatic pressure (HHP) used for treatment of foods. Although the science of biomaterials exposed to high pressure started more than a century ago, there still seem to be a number of unanswered questions regarding safety of foods processed using HHP. This review gives an overview on historical development and fundamental aspects of HHP, as well as on potential risks associated with HHP food applications based on available literature. Beside the combination of pressure and temperature, as major factors impacting inactivation of vegetative bacterial cells, bacterial endospores, viruses, and parasites, factors, such as food matrix, water content, presence of dissolved substances, and pH value, also have significant influence on their inactivation by pressure. As a result, pressure treatment of foods should be considered for specific food groups and in accordance with their specific chemical and physical properties. The pressure necessary for inactivation of viruses is in many instances slightly lower than that for vegetative bacterial cells; however, data for food relevant human virus types are missing due to the lack of methods for determining their infectivity. Parasites can be inactivated by comparatively lower pressure than vegetative bacterial cells. The degrees to which chemical reactions progress under pressure treatments are different to those of conventional thermal processes, for example, HHP leads to lower amounts of acrylamide and furan. Additionally, the formation of new unknown or unexpected substances has not yet been observed. To date, no safety-relevant chemical changes have been described for foods treated by HHP. Based on existing sensitization to non-HHP-treated food, the allergenic potential of HHP-treated food is more likely to be equivalent to untreated food. Initial findings on changes in packaging materials under HHP have not yet been adequately supported by scientific data. 相似文献
954.
955.
Ng N Prabandari YS Padmawati RS Okah F Haddock CK Nichter M Nichter M Muramoto M Poston WS Pyle SA Mahardinata N Lando HA 《Tobacco control》2007,16(3):190-196
Objective
To explore Indonesian physician''s smoking behaviours, their attitudes and clinical practices towards smoking cessation.Design
Cross‐sectional survey.Setting
Physicians working in Jogjakarta Province, Indonesia, between October and December 2003.Subjects
447 of 690 (65%) physicians with clinical responsibilities responded to the survey (236 men, 211 women), of which 15% were medical faculty, 35% residents and 50% community physicians.Results
22% of male (n = 50) and 1% of female (n = 2) physicians were current smokers. Approximately 72% of physicians did not routinely ask about their patient''s smoking status. A majority of physicians (80%) believed that smoking up to 10 cigarettes a day was not harmful for health. The predictors for asking patients about smoking were being male, a non‐smoker and a medical resident. The odds of advising patients to quit were significantly greater among physicians who perceived themselves as sufficiently trained in smoking cessation.Conclusions
Lack of training in smoking cessation seems to be a major obstacle to physicians actively engaging in smoking cessation activities. Indonesian physicians need to be educated on the importance of routinely asking their patients about their tobacco use and offering practical advice on how to quit smoking.Tobacco use is one of the greatest causes of preventable deaths and disease in human history. According to the World Bank, four‐fifths of the world''s 1.1 billion smokers live in low‐income or middle‐income countries.1 East Asian and Pacific countries currently account for about 38% of the world''s smokers and men, especially those aged 30–49 years, account for about 80% of these smokers.2 In Indonesia, 59% of male, but only <5% of women, smoke.3 Notably, the rates of tobacco use, especially among adolescents and young adults in East Asia, continue to rise.1 Although reliable national data are unavailable for Indonesia, estimates in 2004 showed a high incidence rate of tobacco‐attributable mortality and morbidity.4 For example, in 2002, the International Agency of Research on Cancer Globocan estimated that the age‐standardised mortality of respiratory tract cancer in Indonesia among men was 68.5 per 100 000 population, but that among women was only 21.5 per 100 000 population.5Nations such as Indonesia continue to bear significant health and socioeconomic burdens associated with tobacco use, primarily due to aggressive tobacco industries marketing and the slow progress in tobacco control activities resulting from a strong dependency of the national economy on the tobacco trade.6 To reduce the economic and health burden from cigarette smoking, effective measures for smoking cessation and tobacco control are clearly needed. Public health education, and governmental policies such as taxation on sales and restrictions on advertisement may serve as useful tools to limit the use of tobacco products.7,8 Currently, such measures are lacking in Indonesia.Smoking behaviour and attitudes towards smoking cessation by healthcare providers in Western countries have been studied extensively.9,10,11 Research findings suggest that asking about smoking and offering advice about cessation help smokers quit.12,13,14,15,16 Of equal importance is the observation that the smoking status of healthcare providers may influence their willingness to offer smoking cessation advice to smokers.16,17 Unfortunately, limited research is available on non‐Western countries in regard to behaviours, perceptions and attitudes towards smoking among physicians and other healthcare providers.16,18,19,20Understanding the attitudes of health professionals towards cessation of tobacco use is an important early step in the development of a country''s comprehensive anti‐tobacco initiative. This step is especially important in countries like Indonesia, where there are few anti‐tobacco initiatives and physicians play a particularly important role as opinion leaders and role models. To understand physician''s attitudes towards tobacco, we conducted a survey of physicians to explore a range of issues including smoking behaviours, and their attitudes and clinical practices regarding smoking. 相似文献956.
Christine Rühmkorf Heinrich Rübsam Thomas Becker Christian Bork Kristin Voiges Petra Mischnick Markus J. Brandt Rudi F. Vogel 《European Food Research and Technology》2012,235(1):139-146
The effect of structurally different bacterial homoexopolysaccharides on gluten-free bread quality and their properties to act as hydrocolloids was investigated. Furthermore, exopolysaccharides (EPS) were analyzed structurally by asymmetrical flow field flow fractionation and methylation analysis. Breads were made of buckwheat and rice flour with EPS of Lactobacillus (L.) curvatus TMW 1.624, L. reuteri TMW 1.106, L. animalis TMW 1.971, and L. sanfranciscensis TMW 1.392 or hydroxypropylmethylcellulose (HPMC) at 1?% w/w flour base. Water-holding capacity, specific volume, crumb analysis, baking loss, moisture content, and crumb hardness were determined. Only HPMC and the glucan of L. curvatus TMW 1.624 retained water, and all supplements increased the specific volume. Furthermore, crumb hardness was decreased by additives to different extents. The moisture content, baking loss, and crumb firmness were improved most by dextran of L. curvatus TMW 1.624. Structure analysis of EPS revealed that L. animalis TMW 1.971 produces a fructan and a glucan and that the dextran of L. curvatus TMW 1.624 had highest molecular weight of analyzed EPS, ranging from 118 to 242 MDa. A methylation analysis demonstrated differences in branching. Dextran of L. reuteri TMW 1.106 is branched in position 4 (18?C19?%), whereas dextran of L. curvatus TMW 1.624 is branched in position 3 (8?C9?%). Overall, this study gives insight into structure function relations of different EPS. A structure function relation is suggested in which high weight average molar mass (Mw) and branching at position 3 of the glucose monomer foster a compact conformation of the molecule, which enables an increased water-binding capacity and promotes superior (structural) effects in gluten-free breads. The dextran of L. curvatus TMW 1.624 was the most promising candidate for applications in gluten-free bread quality improvements as it retains its size distribution and root mean square even with increasing Mw and forms an increasingly compact molecule. 相似文献
957.
Heavy metal removal from sewage sludge ash by thermochemical treatment with gaseous hydrochloric acid 总被引:1,自引:0,他引:1
Sewage sludge ash (SSA) is a suitable raw material for fertilizers due to its high phosphorus (P) content. However, heavy metals must be removed before agricultural application and P should be transferred into a bioavailable form. The utilization of gaseous hydrochloric acid for thermochemical heavy metal removal from SSA at approximately 1000 °C was investigated and compared to the utilization of alkaline earth metal chlorides. The heavy metal removal efficiency increased as expected with higher gas concentration, longer retention time and higher temperature. Equivalent heavy metal removal efficiency were achieved with these different Cl-donors under comparable conditions (150 g Cl/kg SSA, 1000 °C). In contrast, the bioavailability of the P-bearing compounds present in the SSA after thermal treatment with gaseous HCl was not as good as the bioavailability of the P-bearing compounds formed by the utilization of magnesium chloride. This disadvantage was overcome by mixing MgCO(3) as an Mg-donor to the SSA before thermochemical treatment with the gaseous Cl-donor. A test series under systematic variation of the operational parameters showed that copper removal is more depending on the retention time than the removal of zinc. Zn-removal was declined by a decreasing ratio of the partial pressures of ZnCl(2) and water. 相似文献
958.
Gabriel Adegoke Ronke Gbadamosi Felix Evwoerhurhoma Phyllis Uzo-peters Kolawole Falade Olu Itiola Olanrewanju Moody Brent Skura 《European Food Research and Technology》2002,214(5):408-411
When maize and soybeans were stored under ambient conditions (26ǃ °C/RH 75LJ%) using the ground material of the spice Aframomum danielli (family Zingiberaceae), mouldiness and insect infestation were controlled for 15 months. After eight weeks of storage, chemical compositions of maize and soybeans (moisture content, mc 10.0%) treated with 4.0%, 6.0% and 8.0% ground powder of A. danielli did not differ significantly (P=0.05) from those of untreated (control) samples. However, chemical compositions of samples maintained at 15.0% and 20.0% mc respectively were different from those of control samples (P>0.05). At 10.0% mc, maize and soybean samples treated with different concentrations of A. danielli powder were preferred to treated samples maintained at 15.0% and 20.0% respectively. The preservative capability of the powder of A. danielli was associated with phytochemical components tentatively identified as alkaloids. Viability of maize and soybeans was not affected by treatment with A. danielli powder. The powder of A. danielli has some protective effects on liver cells because it exerted no hepatotoxic effect on test albino rats as serum enzyme levels of glutamate oxaloacetate transmaminase (SGOT), glutamate pyruvate transaminase (SGPT) and alkaline phosphatase (ALP) were lowered by 67.0%, 86.3% and 49.7% respectively when compared with control albino rats not fed with A. danielli powder in their rations (meals). 相似文献
959.
Dittmar J Voegelin A Maurer F Roberts LC Hug SJ Saha GC Ali MA Badruzzaman AB Kretzschmar R 《Environmental science & technology》2010,44(23):8842-8848
Groundwater rich in arsenic (As) is extensively used for dry season boro rice cultivation in Bangladesh, leading to long-term As accumulation in soils. This may result in increasing levels of As in rice straw and grain, and eventually, in decreasing rice yields due to As phytotoxicity. In this study, we investigated the As contents of rice straw and grain over three consecutive harvest seasons (2005-2007) in a paddy field in Munshiganj, Bangladesh, which exhibits a documented gradient in soil As caused by annual irrigation with As-rich groundwater since the early 1990s. The field data revealed that straw and grain As concentrations were elevated in the field and highest near the irrigation water inlet, where As concentrations in both soil and irrigation water were highest. Additionally, a pot experiment with soils and rice seeds from the field site was carried out in which soil and irrigation water As were varied in a full factorial design. The results suggested that both soil As accumulated in previous years and As freshly introduced with irrigation water influence As uptake during rice growth. At similar soil As contents, plants grown in pots exhibited similar grain and straw As contents as plants grown in the field. This suggested that the results from pot experiments performed at higher soil As levels can be used to assess the effect of continuing soil As accumulation on As content and yield of rice. On the basis of a recently published scenario of long-term As accumulation at the study site, we estimate that, under unchanged irrigation practice, average grain As concentrations will increase from currently ~0.15 mg As kg(-1) to 0.25-0.58 mg As kg(-1) by the year 2050. This translates to a 1.5-3.8 times higher As intake by the local population via rice, possibly exceeding the provisional tolerable As intake value defined by FAO/WHO. 相似文献
960.
Reich F Atanassova V Haunhorst E Klein G 《International journal of food microbiology》2008,127(1-2):116-120
For the presence and number of Campylobacter, 18 broiler flocks were sampled over a period of 18 months. A total of 70% of the flocks were positive for Campylobacter, with higher prevalence found in summer and autumn, compared to winter and spring. Positive flocks showed contamination rates above 90%, in negative flocks this was lower, mostly below 50%. The enumeration showed a decrease in Campylobacter during processing of positive flocks. The numbers were highest in carcasses after scalding/defeathering (mean 5.9 log(10) cfu/carcass) and dropped by 0.7 log(10) cfu/carcass after chilling. A positive correlation was observed between the number of Campylobacter present in the caeca and the number of bacteria present on carcasses and cut products. When a negative flock was slaughtered after Campylobacter positive flocks, the number of positive samples was higher compared to the case when a negative flock had been slaughtered previously. C. jejuni was isolated from 73.6% of the poultry samples. 相似文献