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Food Environment (food + environment)
Selected AbstractsInfluence of temperature on biofilm formation by Listeria monocytogenes on various food-contact surfaces: relationship with motility and cell surface hydrophobicityJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2008G. Di Bonaventura Abstract Aims:, To assess the ability of Listeria monocytogenes to form biofilm on different food-contact surfaces with regard to different temperatures, cellular hydrophobicity and motility. Methods and Results:, Forty-four L. monocytogenes strains from food and food environment were tested for biofilm formation by crystal violet staining. Biofilm levels were significantly higher on glass at 4, 12 and 22°C, as compared with polystyrene and stainless steel. At 37°C, L. monocytogenes produced biofilm at significantly higher levels on glass and stainless steel, as compared with polystyrene. Hydrophobicity was significantly (P < 0·05) higher at 37°C than at 4, 12 and 22°C. Thirty (68·2%) of 44 strains tested showed swimming at 22°C and 4 (9·1%) of those were also motile at 12°C. No correlation was observed between swimming and biofilm production. Conclusions:,L. monocytogenes can adhere to and form biofilms on food-processing surfaces. Biofilm formation is significantly influenced by temperature, probably modifying cell surface hydrophobicity. Significance and Impacts of the Study:, Biofilm formation creates major problems in the food industry because it may represent an important source of food contamination. Our results are therefore important in finding ways to prevent contamination because they contribute to a better understanding on how L. monocytogenes can establish biofilms in food industry and therefore survive in the processing environment. [source] Fluctuating asymmetry of sexual and nonsexual traits in stalk-eyed flies: a poor indicator of developmental stress and genetic qualityJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 1 2000Bjorksten It has been proposed that females use fluctuating asymmetry (FA) in sexual ornaments to assess male quality. FA of sexual traits is predicted to show greater sensitivity to stress than FA of nonsexual traits, and to be heritable. We used a half-sib mating design and manipulation of larval food environment to test these predictions on stalk-eyed flies, Cyrtodiopsis dalmanni, in which females prefer males with larger eyespans. We measured size and FA of eyestalks and of two nonsexually selected characters, wing length and width. We found no evidence of an increase in FA under larval food stress in any of the individual traits, although trait size decreased under stress. We combined FA across traits into a single composite index, and found that males reared in the most benign larval environment had significantly higher composite FA than males reared on other media. There was no such effect in females. Heritability of FA was not significantly different from zero in any of the traits, in any of the environments, although trait sizes showed high heritability. We conclude that FA in sexual and nonsexual traits is a poor indicator of developmental stress and genetic quality. [source] Schoolchildren's Consumption of Competitive Foods and Beverages, Excluding à la Carte,JOURNAL OF SCHOOL HEALTH, Issue 9 2010Madhuri Kakarala MD BACKGROUND: Competitive foods/beverages are those in school vending machines, school stores, snack bars, special sales, and items sold à la carte in the school cafeteria that compete with United States Department of Agriculture (USDA) meal program offerings. Grouping à la carte items with less nutritious items allowed in less regulated venues may obfuscate analysis of the school competitive food environment. Excluding à la carte items from competitive foods, the objectives were to: (1) assess competitive food use by gender, ethnicity, eligibility for free or reduced-price meals, and participation in school meals programs, (2) determine differences between grade levels in energy intakes obtained from food sources, (3) determine the nutrient intake derived from competitive foods for students who consumed them, and (4) determine energy-adjusted differences in 24-hour nutrient intakes of protein, calcium, iron, and other selected nutrients between competitive food consumer and nonconsumers. METHODS: Competitive foods/beverages use, excluding à la carte items, was examined using the third School Nutrition Dietary Assessment Study (SNDA III), a nationally representative sample of 2309 schoolchildren in grades 1 to 12. Mean nutrient intakes were adjusted for energy intake and other covariates, and differences between consumers and nonconsumers of competitive items were determined using analysis of variance and sudaan. RESULTS: Excluding à la carte items, 22% of schoolchildren consumed competitive items in a representative school day and use was highest in high school. Consumers of competitive items other than à la carte had significantly higher mean energy, sugar intakes, and lower sodium, dietary fiber, B vitamins, and iron intakes than nonconsumers. CONCLUSIONS: Use of competitive foods/beverages, excluding à la carte, was detrimental to children's diet quality. [source] Development and demonstration of RNA isolation and RT,PCR procedures to detect Escherichia coli O157:H7 gene expression on beef carcass surfacesLETTERS IN APPLIED MICROBIOLOGY, Issue 4 2000E.D. Berry Preventing the development of pathogen resistance to processing and preservation techniques will require an understanding of the genetic mechanisms that pathogens use in situ to adapt and develop tolerance to stresses they encounter in the food environment. RNA isolation and reverse-transcription (RT),PCR protocols were developed as tools to detect gene expression in bacteria on beef carcass surfaces. The utility of these procedures was demonstrated by detecting the expression of a selectively-inducible green fluorescent protein (GFP) gene in a plasmid-transformed strain of Escherichia coli O157:H7 inoculated onto beef carcass surface tissue. These procedures should serve as useful tools for studying the genetic responses of bacteria when exposed to antimicrobial interventions applied to food animal carcasses. [source] Cyber claims: How do we protect public health nutrition within a rapidly changing food environment?NUTRITION & DIETETICS, Issue 3 2006Mark Lawrence PhD [source] Model of the home food environment pertaining to childhood obesityNUTRITION REVIEWS, Issue 3 2008Richard R Rosenkranz The home food environment can be conceptualized as overlapping interactive domains composed of built and natural, sociocultural, political and economic, micro-level and macro-level environments. Each type and level of environment uniquely contributes influence through a mosaic of determinants depicting the home food environment as a major setting for shaping child dietary behavior and the development of obesity. Obesity is a multifactorial problem, and the home food environmental aspects described here represent a substantial part of the full environmental context in which a child grows, develops, eats, and behaves. The present review includes selected literature relevant to the home food environment's influence on obesity with the aim of presenting an ecologically informed model for future research and intervention in the home food environment. [source] Measurement of Food Availability in the HomeNUTRITION REVIEWS, Issue 2 2006Maria Bryant PhD The importance of environment on food choices has recently received increased attention. One environment likely to be influential is the home food environment. This review examines 23 studies that used either researcher-conducted open inventories or self-report checklists to assess food availability in the home. Only three were open inventories (this technique is rarely used, most likely because of low feasibility). Self-report checklists varied in length and the items included. Two checklists, validated using observation, showed high sensitivity and specificity (87% or above). We provide recommendations to develop and validate population-specific tools that measure home food availability. [source] | |||||||||||||