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At least 181 records · Page 10Linked to original sources
PubMed2006

Concentrations of perfluorooctanesulfonamides in Canadian total diet study composite food samples collected between 1992 and 2004.

Canadian Total Diet Study composite samples collected from 1992 to 2004 (n = 151) were analyzed for a series of perfluorooctanesulfonamides that are likely breakdown products or manufacturing residuals associated with perfluorooctylsulfonyl phosphate esters. These esters have been incorporated into coatings for paper and paperboard used in food packaging. N-Ethylperfluorooctanesulfonamide (N-EtPFOSA), perfluorooctanesulfonamide, N,N-diethylperfluorooctanesulfonamide, N-methylperfluorooctanesulfonamide, and N,N-dimethylperfluorooctanesulfonamide were extracted using solvent extraction and quantified by gas chromatography-mass spectrometry. Perfluorooctanesulfonamides were detected in the picograms per gram to low nanograms per gram of wet weight range in all food groups tested-baked goods and candy, dairy, eggs, fast food, fish, meat, and foods to be prepared in packaging. The highest concentrations of total perfluorooctanesulfonamides were observed in fast food composites (from less than the method detection limit to 27300 pg/g of wet weight). Concentrations of N-EtPFOSA appeared to decrease over the sampling period (1992-2004) in French fries and other fast food composites; no such trend was apparent in freshwater fish, marine fish, and shellfish composites. A basic estimate of dietary exposure to perfluorooctanesulfonamides suggests that Canadians (>12 years old) are exposed to approximately 73 ng/person/day from these foods.

Canada↗
PubMed1993

Improvements in the microbiological quality of food samples from a hospital cook-chill system since the introduction of HACCP.

A cook-chill system of catering was introduced in Waterford Regional Hospital in December 1989. An intensive system of microbiological monitoring was put in place from day one and after 16 months a Hazard Analysis Critical Control Point (HACCP) system was introduced. Continuous monitoring showed an improvement in the microbiological quality of the food when using HACCP, with more than 90% of samples having total viable counts of less than 1 x 10(3) g-1 and the virtual elimination of pathogens. The introduction of HACCP allowed a reduction in the level of sampling and provided a useful set of records for quality assurance.

Cooking↗
PubMed1994

Determination of sterol content in different food samples by capillary gas chromatography.

An accurate method for the determination of sterols by capillary gas chromatography was developed and applied to the analysis of food. The procedure includes the following steps: dichloromethane-methanol (2:1, v/v) lipid extraction, saponification at 80 degrees C and separation of the unsaponifiable matter with cyclohexane, derivatization to form trimethylsilyl ethers and gas chromatography using 5 alpha-cholestane as the internal standard. The method shows good accuracy, precision and sensitivity and is suitable for the determination of sterols in food.

Animals↗
PubMed2003

Influence of age and dental status on chewing behaviour studied by EMG recordings during consumption of various food samples.

OBJECTIVE: To evaluate the effects of age and dental status on chewing performance in humans. DESIGN: Electromyography recordings (EMG) were made during chewing of six foods (rice, beef, cheese, crispy bread, apple, and peanuts) to compare the masticatory patterns of four subject groups with different ages and dental status. SUBJECTS: Nineteen elders (mean age 67.2 years) classified into three categories according to their number of opposing post-canine teeth pairs (i.e. functional units) and a control group of 10 young adults (mean age 26.5 years) with a high number of functional units. MAIN OUTCOME MEASURES: Number of chewing cycles, chewing time, total muscle activity and muscle activity per chew, burst and inter-burst durations, maximum and mean voltages from EMG recordings. RESULTS: Time-related EMG parameters increased from young subjects to elderly subjects with high, middle and low dental status. Parameters related to EMG voltages per chew decreased in the same order among the different groups of subjects. These tendencies were observed for all the studied products. Subjects with weak muscle contraction may compensate for their poor chewing performance by lengthening both chewing cycle and sequence duration. Additional alterations in the chewing patterns were observed when age effect was associated with a dental status degradation in terms of number of functional units. CONCLUSION: Impairment in mastication for the elderly is due to both ageing and decreasing number of functional pairs of post-canine teeth.

Adult↗
PubMed1999

Accelerated solvent extraction and gas chromatography/mass spectrometry for determination of polycyclic aromatic hydrocarbons in smoked food samples.

Accelerated solvent extraction (ASE) is a new sample extraction method offering a number of advantages such as low pe -extraction cost, reduced solvent and time consumption, and simplified extraction protocols. In this study, the ASE method was applied to the extraction of polycyclic aromatic hydrocarbons (PAHs) from biological samples. For recovery studies, fish tissues and ground pork were used as sample matrices. Sample aliquots fortified with 16 PAHs were extracted by ASE, and the extracts were treated with sulfuric acid and Florisil, followed by gas chromatography-mass spectrometry analysis. The PAH recoveries by the ASE method were found to be comparable with or better than those by Soxhlet extraction. The extraction and quantitation method was then applied to the determination of PAHs in several smoked meat samples obtained from a local market. Up to 12 PAHs were found to be present at concentrations ranging from 3 to 52 ng/g wet sample.

Food Handling↗
PubMed1984

HPLC analysis with fluorometric detection of vitamin C in food samples.

A high performance liquid chromatographic (HPLC) procedure has been developed for the analysis of ascorbic acid and dehydroascorbic acid in complex matrices. Separation is accomplished with an anion-exchange resin and fluorescent detection is achieved through post-column inline chemistry, involving oxidation of ascorbic acid to dehydroascorbic acid followed by reaction with o-phenylenediamine to form a fluorescent product. Lower limits of detection for both forms of vitamin C are well below the levels found in the usual food sources of this vitamin. The extraction procedures developed yield clean samples for analysis with minimal loss of the vitamers during the analytical procedures. Recoveries are in the range of 90-107%. The results obtained with this HPLC procedure agree well with those obtained with a modified version of the classical procedure of Deutsch and Weeks. A variety of foods including fruit juices, vegetables, and fruits were analyzed.

Ascorbic Acid↗
PubMed1998

Reverse micelle formation for acceleration of the supercritical fluid extraction of cholesterol from food samples.

Reverse micelle formation is presented as a new strategy for improving the extraction of polar species with supercritical (SC) CO2. The addition of a reverse-micelleforming reagent prior to SFE accelerates the quantitative extraction of the analyte. The effect was used to develop a method for the determination of cholesterol in solid foods. The proposed method involves the addition of a microemulsion of a nonionic surfactant (Triton X-100) to the sample and dynamic extraction with SC-CO2 at 383 bar and 40 degrees C for 20-40 min. The method was validated using a certified reference material (NIST-SRM 1845) and was subsequently used to analyze low-cholesterol (whole bread, oat biscuits, orange biscuits) and high-cholesterol foods (semiskimmed and whole milk) with excellent results (RSD < 11% in all instances).

Animals↗
PubMed1991

Detection of Clostridium perfringens type A enterotoxin in faecal and food samples using immunomagnetic separation (IMS)-ELISA.

A simple, rapid and sensitive immunoassay, based on immunomagnetic particles (Dynabeads M-280) was developed for detection and quantitation of Clostridium perfringens type A enterotoxin from faecal and food extracts. The assay had a detection limit of 2.5 ng/ml enterotoxin in homogenates of faeces and inoculated meat extracts. The specificity was confirmed by both crossed immunoelectrophoresis and Western immunoblotting techniques, using a purified enterotoxin as standard.

Animals↗
PubMed1980

Lead-210 content of food samples in India.

The paper presents results of measurements made on cereals and composite meal samples collected from Bombay market for their lead-210 content. The details of sampling and analytical chemistry procedures are also given. The Pb210 contents of most of these samples were in the range of 1--5 pCi/kg of cereals samples. The concentrations in composite meal samples were mostly in the range of 1--3.5 pCi of 210Pb per composite meal. The assessment of daily intake of this isotope through food-stuffs has been made.

Edible Grain↗
PubMed2002

Toxic potency of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and polychlorinated biphenyls in food samples from Catalonia (Spain).

A surveillance program on polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) in 29 foodstuff samples produced all over the four provinces in Catalonia (Spain) is presented. The study included the analyses of milk, egg, meat (beef, chicken, and pork), mussel, and olive oil samples. A previously developed method for the simultaneous analysis of the 2,3,7,8-substituted PCDDs/PCDFs and the dioxin-like PCBs, as well as the indicator PCBs, was employed. Total toxicity equivalent (TEQ) values were calculated using the toxicity equivalent factors (TEFs) proposed by the World Health Organization (WHO) for dioxin-like PCBs, PCDDs, and PCDFs. The TEQ(PCDD/F) levels were below the limits proposed in the draft of the EC regulation for food commercialization in the European countries. These limits are the following: 2 pg WHO-TEQ/g fat for pork, 3 pg WHO-TEQ/g fat for milk and chicken, 5 pg WHO-TEQ/g fat for egg and beef, and 3 pg WHO-TEQ/g whole product for fish. The contributions of PCDDs/Fs and dioxin-like PCBs in the total toxicity of the samples were calculated for each matrix. The results showed that the TEQ(PCB) contribution varied from 27% in olive oil samples to 81% in mussel samples. These findings suggest that the regulation of TEQ contents in food should include not only the TEQ(PCDD/F), but also the TEQ(PCB).

Adipose Tissue↗