Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
68,661
result(s) for
"Food Microbiology"
Sort by:
Prevalence and serotype distribution of Listeria monocytogenes isolated from foods in Montevideo-Uruguay
The aim of this work was to study the prevalence of Listeria monocytogenes in foods obtained in retail shops and food industries located in Montevideo-Uruguay, and to identify the serogroups of the obtained isolates. Three-thousand one-hundred and seventy-five food samples (frozen, deli meats, ready-to-eat and cheese) were analyzed. The obtained isolates were serogrouped by multiplex PCR and serotyped by conventional procedure. Genetic comparisons were performed using pulsed-field gel electrophoresis on a sub-set of isolates belonging to the same serotype successively recovered from the same establishment. L. monocytogenes was isolated from 11.2% of samples. The highest prevalence was observed in frozen foods (38%), followed by cheese (10%). 1/2b and 4b were the most frequently identified serotypes. In six of 236 analyzed establishments we successively recovered L. monocytogenes isolates belonging to the same serotype. Most of them corresponded to serotype 1/2b. Pulsed-field gel electrophoresis profiles suggest that at least 33% of L. monocytogenes 1/2b isolates are genetically related and that may remain viable for prolonged periods. The observed prevalence of L. monocytogenes was lower than reported in neighboring countries. Our findings highlight the role that frozen foods may play in the spread of this pathogen, and the relevance of serotypes 1/2b and 4b.
Journal Article
Riboflavin-overproducing lactobacilli for the enrichment of fermented soymilk: insights into improved nutritional and functional attributes
The influence of riboflavin (B2)–overproducing lactobacilli on the antioxidant status, isoflavone conversion, off-flavor reduction, amino acid profile, and viscosity of B2-bio-enriched fermented soymilk was investigated. Results showed that B2 in fermented soymilk was notably increased from 0.2 to 3.8 μg/mL for Lactobacillus fermentum UFG169 and to 1.9 μg/mL for Lactobacillus plantarum UFG10. The apparent viscosity significantly changed with rising acidity and agglutination of protein. The off-flavor volatile substances (hexanal and nonanal) were significantly reduced in fermented soymilk. Furthermore, a large amount of glucoside form isoflavones was deglycosylated into bioactive aglycones after 4 h up to 32 h. B2 content and isoflavones significantly improved the antioxidant status of soymilk. Partial least squares regression analysis correlated the strain activity and fermentation time with the improved nutritional and functional soymilk qualities. This study demonstrated the strategy for strain development for B2-bio-enriched fermentation to extend the health-promoting benefits of soymilk and soy-related foods.Key points• B2-enriched fermentation enhanced the nutrition and functional status of soymilk.• Fermentation time significantly affected the apparent viscosity of fermented soymilk.• Off-flavor volatile substances were significantly reduced or even diminished.• Increased B2and bioactive isoflavones contributed to improved antioxidant potential.
Journal Article
Dynamic Changes in Biogenic Amine Content in the Traditional Brewing Process of Soy Sauce
A high concentration of biogenic amines have been reported to be hazardous for human health. This article is an analytical report on one lot to identify the changes of biogenic amines in each period of soy sauce brewing and clarify the key control point for biogenic amine production. The content of putrescine, cadaverine, spermidine, spermine, tryptamine, phenylethylamine, histamine, serotonin, tyramine, and agmatine was detected in the
-making and fermenting process. The content of putrescine increased from 27.11 ± 1.05 to 185.86 ± 1.18 mg/kg in the koji-making process, indicating that putrescine is the main biogenic amine produced by microbes in this period. The content of tryptamine increased to the highest value of 581.77 ± 36.38 mg/L on day 24 of the fermenting process and then decreased rapidly to 81.98 ± 0.20 mg/L at the end (day 122). In addition, histamine and tyramine reached the highest values (486.91 ± 24.67 and 180.84 ± 2.32 mg/L, respectively) after 52 days of fermentation, followed by a decrease to 287.24 ± 15.00 and 144.67 ± 3.61 mg/L, respectively, at the end of the fermenting process. The samples were further characterized by the analysis of other indices, including the content of water, salt, soluble saltless solids, crude fat, total acid, amino acid nitrogen, total nitrogen, and ammonium salt. The content of soluble saltless solids decreased from 9.28 ± 0.16 to 5.30 ± 1.40 g/100 g during the first 38 days of fermentation, followed by an increase to 14.68 ± 1.12 g/100 g during the last 84 days. The content of total acid, crude fat, amino acid nitrogen, total nitrogen, and ammonium salt all increased rapidly in the early stage of the fermenting process and then slowed down.
Journal Article
The case of the undercooked burger
\"Learn about E. coli, the round worm A. lumbricoides, hepatitis A, C. jejuni, and Staphylococcus aureus. Then try to guess the disease in three different cases\"-- Provided by publisher.
Book
Multistate outbreak of Salmonella Paratyphi B variant L(+) tartrate(+) and Salmonella Weltevreden infections linked to imported frozen raw tuna: USA, March–July 2015
Foodborne non-typhoidal salmonellosis causes approximately 1 million illnesses annually in the USA. In April 2015, we investigated a multistate outbreak of 65 Salmonella Paratyphi B variant L(+) tartrate(+) infections associated with frozen raw tuna imported from Indonesia, which was consumed raw in sushi. Forty-six (92%) of 50 case-patients interviewed ate sushi during the week before illness onset, and 44 (98%) of 45 who specified ate sushi containing raw tuna. Two outbreak strains were isolated from the samples of frozen raw tuna. Traceback identified a single importer as a common source of tuna consumed by case-patients; this importer issued three voluntary recalls of tuna sourced from one Indonesian processor. Four Salmonella Weltevreden infections were also linked to this outbreak. Whole-genome sequencing was useful in establishing a link between Salmonella isolated from ill people and tuna. This outbreak highlights the continuing foodborne illness risk associated with raw seafood consumption, the importance of processing seafood in a manner that minimises contamination with pathogenic microorganisms and the continuing need to ensure imported foods are safe to eat. People at higher risk for foodborne illness should not consume undercooked animal products, such as raw seafood.
Journal Article
Evaluating the presence of human pathogens in commercially frozen, biologically appropriate raw pet food sold in Italy
BackgroundBiologically appropriate raw food (BARF) diet is becoming more and more popular among pet owners in Europe. However, there are documented microbiological risks associated with raw feeding, and this study aimed to determine the presence of human pathogens in commercially frozen BARF products sold in Italy.Methods Salmonella species, Escherichia coli O157:H7, Listeria monocytogenes and Campylobacter species were identified. The general microbiological quality of BARF products and hygiene were also evaluated. Sample size was limited and therefore the study may not be representative of a larger sample.ResultsNone of the tested samples showed total bacterial count (TBC) higher than the limit set to consider a sample unacceptable. However, 14 out of 21 samples showed TBC higher than the limit set to consider a sample marginally acceptable. A high percentage of samples were contaminated by the aforementioned pathogens, highlighting the need for pet owners to be aware of the risks of this feeding strategy both to themselves and to their pets.ConclusionsConsidering that BARF diet meals can be prepared at home using the hands, as well as tools and spaces that could be shared, guidelines on safer handling of these pet food products should be recommended by veterinarians and nutritionists.
Journal Article