PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Food samples”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources
PubMed1976

Differences between the anorexic actions of amphetamine and fenfluramine--possible effects on hunger and satiety.

The inhition of feeding in rats brought about by amphetamine and fenfluramine was continuously monitored for periods of up to 24 h using a pellet detecting eatometer. For rats tested under conditions of food deprivation the two drugs gave rise to distinctive anorexic profiles: amphetamine delayed the onset of eating whereas fenfluramine allowed eating to commence normally but brought about an early termination of the initial bout of feeding. When the drugs were administrated to rats with free access to food, analysis of the meal pattern showed that amphetamine gave rise to a small increase in the inter-meal interval while fenfluramine brought about a clear reduction tion in meal size. It is suggested that the contrasting modes of action of these drugs represent an effect of amphetamine upon hunger and an action of fenfluramine on satiety. This suggestion is in keeping with the proposed mechanisms of action of these drugs, amphetamine acting upon a hpothalamic motivational system and fenfluramine acting by means of a postulated serotoninergic satiety system. Use of the continuous monitoring technique has pointed pointed to certain limitations in the assessment of anorexic drug action by means of discrete food sampling periods.

Animals↗
PubMed1979

Discrimination learning without short-term memory: dissociation of memory processes in pigeons.

Pigeons were trained to perform delayed matching to samples of food and no food when each sample concurrently served as the outcome of a discrimination learning trial which immediately preceded each matching trial. Ambient light presented during the delays after the samples of food or no food severely disrupted matching but had no effect on the rate of discrimination learning.

Animals↗
PubMed2026

Ribotyping for Accurate Identification of Infectious Bacteria in Animal-Derived Foods and Laboratory Samples: Implications for Human Health.

Ribotyping is a molecular typing approach based on ribosomal RNA (rRNA) gene sequences for the identification and characterization of bacterial strains. This review aims to evaluate the effectiveness of ribotyping in the identification of infectious bacteria in animal-derived foods and veterinary samples. A narrative literature review was conducted using major scientific databases, including PubMed, Scopus, Google Scholar, and Web of Science, covering studies published to 2025. Relevant articles were selected based on their focus on ribotyping methodologies (e.g., RFLP-, PCR-, and automated ribotyping) and their applications in food safety, veterinary microbiology, and zoonotic disease investigations. The findings indicate that ribotyping has been widely applied for epidemiological investigations, source tracking, and characterization of foodborne and zoonotic pathogens. These approaches have contributed to understanding bacterial diversity and monitoring antibiotic resistance patterns in animal populations and related food products. However, compared with high-resolution molecular techniques such as whole genome sequencing (WGS), ribotyping demonstrates lower discriminatory power and limited resolution for fine-scale epidemiological analysis. Despite these limitations, ribotyping remains a useful, accessible, and cost-effective tool in certain laboratory and surveillance settings, particularly where advanced genomic technologies are not readily available. Overall, integrating ribotyping with newer genomic approaches can enhance the monitoring and control of infectious bacteria, thereby supporting animal health, food safety, and public health outcomes.

animal-derived foods↗
PubMed1979

Analysis of foods for iodine: interlaboratory study.

An accurate, reproducible method for less than or equal to 1 ppm iodine in foods is required for nutritional labeling. In order to ascertain the current status of iodine analysis in foods, 7 samples, representing different food classes, were analyzed by 8 laboratories. Six laboratories used their modifications of the Ce-As-I catalytic method preceded by alkaline dry ashing. Two laboratories used neutron activation analysis (NAA), with differing radiochemical separations. The study showed wide discrepancy in analytical results. Mean relative standard deviation for all laboratories was 77.9% between laboratories; 19.1% within-laboratories. Laboratories using NAA had only slightly better precision than did laboratories using the chemical method. The lowest level reported on the entire group of samples ranged among laboratories from 0.0089 to 0.65 ppm. Figures reported by a laboratory are, in general, consistently high or consistently low. The only differences in methodology which may possibly correlate with level of iodine obtained are the use of NAA technique and use of manual, rather than automated, colorimetry.

Colorimetry↗
PubMed1979

Comparison of Stomacher and Waring Blendor for homogenizing foods to be examined for Clostridium perfringens.

The Colworth Stomacher Model 400 homogenizer was compared with the Waring Blendor for preparing food homogenates to be examined for Clostridium perfringens. Forty-eight samples representing 6 different food types were inoculated with C. perfringens and examined by the AOAC official first action method for enumeration of C. perfringens in foods. Identical paired specimens of each food type were blended with the 2 devices, and plate counts were made as specified in the official first action method. The effects of frozen storage on plate counts were determined by examining 24 food samples that had been stored for 3 days at -68 degrees C and homogenized both devices. Results of a statistical analysis of the experimental data indicated no significant difference overall (P greater than 0.05) in the plate counts of homogenates prepared with the Waring Blendor or the Stomacher 400, either before or after frozen storage of the food samples. However, the overall plate count average of the 48 samples was slightly higher with the Waring Blendor than with the Stomacher 400 homogenizer.

Bacteriological Techniques↗
PubMed1977

Double-antibody solid-phase enzyme immunoassay for the detection of staphylococcal enterotoxin A.

A simple double-antibody enzyme immunoassay that uses a microtechnique was developed for detecting staphylococcal enterotoxin A in food products. Sample preparation can be completed in less than 15 min. Assay sensitivity ranges from 0.4 ng (20-h test time) to 3.2 ng (1- to 3-h test time) of toxin per ml of prepared sample. Separation and detection of enterotoxin from spiked food products ranged between 72 and 98% of the amount added.

Enterotoxins↗
PubMedDate not supplied

Food and environmental aspects of infant botulism in California.

In an effort to identify vehicles by which Clostridium botulinum spores might have reached the intestine of patients with infant botulism, 555 samples of foods, drugs, and environmental specimens were examined. Of the food items, C. botulinum was only found in nine of 90 (10%) honey specimens. Five patients had been exposed to honey that contained C. botulinum, and ingestion of honey was found to be a significant risk factor for type B infant botulism (P = 0.005). In addition, C. botulinum was isolated from five samples of soil (three from case homes, two from control homes) and from vacuum cleaner dust from one case home. In every instance in which C. botulinum was isolated from a specimen of honey, soil, or duct associated with a case of infant botulism, the type of toxin (A or B) in the honey, soil, or dust isolate matched the type of toxin of the organism recovered from the infant. Isolation of C. botulinum from the soil of homes of control infants emphasizes the ubiquitous distribution of and exposure to this organism and suggests that host factors are important in the development of illness. Prevention of infant botulism will depend on the identification of these host factors, as well as on the identification of other vehicles that, like honey, may convey C. botulinum spores to susceptible infants.

Botulism↗
PubMed2026

Design of an innovative framework based hybrid catalyst for simultaneous and sensitive monitoring of food additive and preservative of vanillin and nitrite in direct samples.

As vanillin (VAN) and nitrite (NIT) contamination in the food chain poses substantial threats to environmental and public health, rapid and portable detection is essential. The present study presents the first electrochemical sensor report based on a hybrid composite of Ni-TPA-MOF and MoS2/Co3O4. The oxidation of VAN and NIT exhibited sharp peaks and less over-potential on Ni-TPA-MOF/MoS2/Co3O4/GCE than on control electrode surfaces. On modified composite electrode surfaces, pH and scan rate were investigated for VAN and NIT. Further, the oxidation current exhibited high linearity at VAN and NIT concentrations of 5 nM-1000 μM and 3 nM-1250 μM, with detection limits of 0.102 nM and 0.073 nM (S/N = 3). We also applied anti-interfering ability (five/ten-fold excess of co-interfering compounds) and practical tests to various food-based real samples, with high recoveries of 98.85-102.41%. This study highlights the catalytic properties of Ni-TPA-MOF/MoS2/Co3O4 and demonstrates the sensor as a promising tool for food safety.

Benzaldehydes↗
PubMed1979

[Hygienic significance of sterigmatocystin in vegetable foods. 3. Occurrence of sterigmatocystin].

A total of 142 samples of vegetable foods was examined for the occurrence of sterigmatocystin. The samples examined were fruits and vegetables which had spontaneously gone mouldy or begun to rot under natural conditions on the one hand, and organoleptically impeccable fruit juices and maize specimens on the other hand. The samples were taken at the manufacturing plant or procured on the market in the framework of operative controls. Sterigmatocystin was detected in none of the samples under investigation. From this it may be concluded that the risk of its occurrence in vegetable foods is not very great in our country. Nevertheless, due to its cancerogenic and toxic properties, sterigmatocystin should remain included in the examination for mycotoxins in the framework of food control.

Fruit↗
PubMed1977

Anti-microbial treatment for hospital carpets.

Seven commercial bactericides, three hospital disinfectants and one carpet finish were examined for their ability to show diffusible bactericidal activity in agar, their ability to prevent the multiplication of a known number of micro-organisms applied to the treated carpet and the occurrence or otherwise of odours after contamination of the carpet samples with food and secretions. None of the carpet bactericides tested showed any diffusible bactericidal activity, but some had a certain degree of effectiveness in suppressing odours.

Ammonia↗
PubMed1977

Aflatoxin and liver cancer in Karachi, a preliminary survey.

A cause and effect relationship of Aflatoxin and liver cancer is well established. The incidence of liver cancer is 3.6% in Karachi (Zuberi et al., 1976) and Aflatoxins have been detected in 43% of 28 samples of food analysed in this study. The long term ingestion of aflatoxin with food may have some effect on the existing pattern of liver cancer in Karachi.

Aflatoxins↗
PubMed1979

Atomic absorption determination of tin in foods: collaborative study.

Samples of green beans, applesauce, and a fruit juice were fortified with tin at 3 levels. Collaborators were asked to digest the samples, using HNO3-H2SO4, add methanol to enhance the absorption signal, and aspirate directly, using a nitrous oxide-acetylene flame. Results were received from 8 laboratories including 4 from Europe. However, only 6 laboratories used the prescribed methodology. All results were considered acceptable. The method has been adopted as interim official first action.

Beverages↗
PubMed1979

Sample homogenization procedure for determination of lead in canned foods.

To improve the homogeneity of canned foods before Pb determination, composited samples or single can contents (150--500 g) are treated with an equal weight of dilute nitric acid, and then thoroughly blended in a high efficiency, probe-type Polytron homogenizer; subsamples are then either dry-ashed or wet-ashed in preparation for analysis. Within-can variability is reduced from the 20--50% coefficient of variation range obtained with conventional blending procedures to a coefficient of variation of less than 5% by using the proceudre described. Precision data for Pb, using both the probe-type and conventional blade-type homogenizers, are compared. The procedure described for Pb determination was used to analyze a number of canned products. Data indicate that the Polytron plus dilute acid procedure improves overall Pb homogeneity for subtle as well as severe initial Pb heterogeneity.

Food Analysis↗
PubMed1977

The reliability of the examination of foods, processed for safety, for enteric pathogens and Enterobacteriaceae: a mathematical and ecological study.

Because of the paucity of quantitative data on numbers of other enteric pathogens in food, the reliability of the examination of processed foods for Enterobacteriaceae was estimated taking Salmonella as a model. For this purpose an assessment was carried out of the risk of accepting Salmonella contaminated consignments of foods, despite a negative outcome of (i) examination of 1.5 kg samples for Salmonella; (ii) examination of one or two 1 g samples for Enterobacteriaceae; (iii) simultaneous application of both tests. The computations were based on the results of the examination of 6830 samples of dried foods, processed for safety, out of a total of 18170 samples.Only 69 samples permitted the exact calculation of the epsilon-factor, defined as c.f.u./g of Enterobacteriaceae/c.f.u./g of Salmonella; 4642 were positive for the former group but ;free' from Salmonella, and the rest were negative in both tests. Numbers of c.f.u./g for both groups, and hence the epsilon-factors, varied widely between commodities and also between different consignments of the same food product. The average for epsilon amounted to 5.8 x 10(3), far from the base-line value of 0.75 x 10(3) assessed earlier. In only 0.1% of samples did the Enterobacteriaceae test fail to achieve the required consumer protection.This investigation therefore substantiates that testing foods processed for safety by examining accurately chosen quantities for ecologically well selected and taxonomically thoroughly defined index organisms is a most effective procedure in terms both of consumer protection and simplicity of examination without compelling the food industry to achieve hardly attainable microbiological quality standards.

Bacteriological Techniques↗
PubMed1977

Collaborative study of a method for the detection of Clostridium botulinum and its toxins in foods.

The mouse toxicity and protection technique for the detection and identification of Clostridium botulinum and its toxins in foods was collaboratively studied by 11 laboratories. Each laboratory received 4 samples of cream of mushroom soup; 2 contained spores and toxin of C. botulinum type A, 1 contained spores and toxin of C. botulinum type E, and 1 contained spores of C. sporogenes. The media used were cooked meat medium (beef heart or chopped liver broth) and trypticase peptone glucose yeast extract broth with trypsin. The results indicate that this method has a high degree of repeatability and reproducibility. All 11 laboratories correctly identified the toxins and the nontoxic sample in the food and detected and identified the viable spores in the samples by means of the subsequent cultures. This method has been adopted as official first action.

Biological Assay↗
PubMed1979

[Hygienic significance of patulin in food. 2. Occurrence of patulin in fruit and vegetables].

The analyses of more than 200 samples of various foods of plant origin showed that patulin was contained in 36% of the fresh and canned fruits infested with mould, and in 7% of the vegetables. Besides apples, pears, plums, peaches and tomatoes contained also patulin. In organoleptically impeccable fruit juices, the contamination rates were 40% (for apple juice) and 16% (for the other juices, such as sour cherry, currant, sea buckthorn juices). The patulin content varied from 20 to 200 microgram/l, the mean value being 80 microgram/l. It ranged from 0.1 to 5 microgram/g in apples and sterile apple preserves. The authors discuss the hygienic-toxicologic significance of these findings, and suggest to include patulin in the examination of foods for mycotoxins, stipulating a permissible value.

Food Analysis↗