From food to offspring down : tissue-specific discrimination and turn-over of stable isotopes in herbivorous waterbirds and other avian foraging guilds

Isotopic discrimination and turn-over are fundamental to the application of stable isotope ecology in animals. However, detailed information for specific tissues and species are widely lacking, notably for herbivorous species. We provide details on tissue-specific carbon and nitrogen discrimination and turn-over times from food to blood, feathers, claws, egg tissues and offspring down feathers in four species of herbivorous waterbirds. Source-to-tissue discrimination factors for carbon (δ¹³C) and nitrogen stable isotope ratios (δ¹⁵N) showed little variation across species but varied between tissues. Apparent discrimination factors ranged between −0.5 to 2.5‰ for δ¹³C and 2.8 to 5.2‰ for δ¹⁵N, and were more similar between blood components than between keratinous tissues or egg tissue. Comparing these results with published data from other species we found no effect of foraging guild on discrimination factors for carbon but a significant foraging-guild effect for nitrogen discrimination factors.

Turn-over of δ¹³C in tissues was most rapid in blood plasma, with a half-life of 4.3 d, whereas δ¹³C in blood cells had a half-life of approximately 32 d. Turn-over times for albumen and yolk in laying females were similar to those of blood plasma, at 3.2 and 6.0 d respectively. Within yolk, we found decreasing half-life times of δ¹³C from inner yolk (13.3 d) to outer yolk (3.1 d), related to the temporal pattern of tissue formation.

We found similarities in tissue-specific turn-over times across all avian species studied to date. Yet, while generalities regarding discrimination factors and tissue turn-over times can be made, a large amount of variation remains unexplained.

Expanding children's food experiences : the impact of a school-based kitchen garden program

Objective: Evaluate achievement of the Stephanie Alexander Kitchen Garden Program in increasing child appreciation of diverse, healthy foods.

Design: Comparative 2-year study.

Setting: Six program and 6 comparison primary schools in rural and metropolitan Victoria, Australia, matched for socioeconomic status and size.

Participants: A total of 764 children in grades 3 to 6 (8–12 years of age) and 562 parents recruited. Retention rates at follow-up included 85% children and 75% parents.

Intervention: Each week of the school year, children spent 45 to 60 minutes in a garden class and 90 minutes in a kitchen class.

Phenomenon of interest: Program impact on children’s willingness to try new foods, capacity to describe foods, and healthy eating.

Analysis: Qualitative data analyzed using inductive thematic analysis. Quantitative data analyzed using random-effects linear regressions adjusted for school clustering.

Results: Child and parent qualitative and quantitative measures (if never tried before, odds ratio 2.0; confidence interval, 1.06–3.58) showed increases in children’s reported willingness to try new foods. No differences in articulation of food descriptions (program vs comparison groups). Qualitative evidence showed that the program extended its influence to healthy eating, but this was not reflected in the quantitative evidence.

Conclusions and Implications: Findings indicate program success in achieving its primary objective, meriting further program research.

More rapid and severe disease outbreaks for aquaculture at the tropics : implications for food security

1. Aquaculture is replacing capture fisheries in supplying the world with dietary protein. Although disease is a major threat to aquaculture production, the underlying global epidemiological patterns are unknown. 2. We analysed disease outbreak severity across different latitudes in a diverse range of aquaculture systems. 3. Disease at lower latitudes progresses more rapidly and results in higher cumulative mortality, in particular at early stages of development and in shellfish. 4. Tropical countries suffer proportionally greater losses in aquaculture during disease outbreaks and have less time to mitigate losses. 5. Synthesis and applications. Disease can present a major problem for food production and security in equatorial regions where fish and shellfish provide a major source of dietary protein. As the incidences of some infectious diseases may increase with climate change, adaptation strategies must consider global patterns in disease vulnerability of aquaculture and develop options to minimize impacts on food production.

Barriers to avoiding fast-food consumption in an environment supportive of unhealthy eating

Objective
To investigate factors (ability, motivation and the environment) that act as barriers to limiting fast-food consumption in women who live in an environment that is supportive of poor eating habits.

Design
Cross-sectional study using self-reports of individual-level data and objectively measured environmental data. Multilevel logistic regression was used to assess factors associated with frequency of fast-food consumption.

Setting
Socio-economically disadvantaged areas in metropolitan Melbourne, Australia.

Subjects
Women (n 932) from thirty-two socio-economically disadvantaged neighbourhoods living within 3 km of six or more fast-food restaurants. Women were randomly sampled in 2007–2008 as part of baseline data collection for the Resilience for Eating and Activity Despite Inequality (READI) study.

Results
Consuming low amounts of fast food was less likely in women with lower perceived ability to shop for and cook healthy foods, lower frequency of family dining, lower family support for healthy eating, more women acquaintances who eat fast food regularly and who lived further from the nearest supermarket. When modelled with the other significant factors, a lower perceived shopping ability, mid levels of family support and living further from the nearest supermarket remained significant. Among those who did not perceive fruits and vegetables to be of high quality, less frequent fast-food consumption was further reduced for those with the lowest confidence in their shopping ability.

Conclusions
Interventions designed to improve women's ability and opportunities to shop for healthy foods may be of value in making those who live in high-risk environments better able to eat healthily.

Independent and joint associations of TV viewing time and snack food consumption with the metabolic syndrome and its components; a cross-sectional study in Australian adults

Background:
Television (TV) viewing time is positively associated with the metabolic syndrome (MetS) in adults. However, the mechanisms through which TV viewing time is associated with MetS risk remain unclear. There is evidence that the consumption of energy-dense, nutrient poor snack foods increases during TV viewing time among adults, suggesting that these behaviors may jointly contribute towards MetS risk. While the association between TV viewing time and the MetS has previously been shown to be independent of adult’s overall dietary intake, the specific influence of snack food consumption on the relationship is yet to be investigated. The purpose of this study was to examine the independent and joint associations of daily TV viewing time and snack food consumption with the MetS and its components in a sample of Australian adults.

Methods:
Population-based, cross-sectional study of 3,110 women and 2,572 men (>35 years) without diabetes or cardiovascular disease. Participants were recruited between May 1999 and Dec 2000 in the six states and the Northern Territory of Australia. Participants were categorised according to self-reported TV viewing time (low: 0-2 hr/d; high: >2 hr/d) and/or consumption of snack foods (low: 0-3 serves/d; high: >3 serves/d). Multivariate odds ratios [95% CI] for the MetS and its components were estimated using gender-specific, forced entry logistic regression.

Results:
OR [95% CI] for the MetS was 3.59 [2.25, 5.74] (p≤0.001) in women and 1.45 [1.02, 3.45] (p = 0.04) in men who jointly reported high TV viewing time and high snack food consumption. Obesity, insulin resistance and hypertension (women only) were also jointly associated with high TV viewing time and high snack food consumption. Further adjustment for diet quality and central adiposity maintained the associations in women. High snack food consumption was also shown to be independently associated with MetS risk [OR: 1.94 (95% CI: 1.45, 2.60), p < 0.001] and hypertension [OR: 1.43 (95% CI: 1.01, 2.02), p = 0.05] in women only. For both men and women, high TV viewing time was independently associated with the MetS and its individual components (except hypertension).

Conclusion:
TV viewing time and snack food consumption are independently and jointly associated with the MetS and its components, particularly in women. In addition to physical activity, population strategies targeting MetS prevention should address high TV time and excessive snack food intake.

Stable isotope-based community metrics as a tool to identify patterns in food web structure in east African estuaries

1.Quantitative tools to describe biological communities are important for conservation and ecological management. The analysis of trophic structure can be used to quantitatively describe communities. Stable isotope analysis is useful to describe trophic organization, but statistical models that allow the identification of general patterns and comparisons between systems/sampling periods have only recently been developed. 2.Here, stable isotope-based Bayesian community-wide metrics are used to investigate patterns in trophic structure in five estuaries that differ in size, sediment yield and catchment vegetation cover (C3/C4): the Zambezi in Mozambique, the Tana in Kenya and the Rianila, the Betsiboka and Pangalanes Canal (sampled at Ambila) in Madagascar. 3.Primary producers, invertebrates and fish of different trophic ecologies were sampled at each estuary before and after the 2010–2011 wet season. Trophic length, estimated based on δ15N, varied between 3·6 (Ambila) and 4·7 levels (Zambezi) and did not vary seasonally for any estuary. Trophic structure differed the most at Ambila, where trophic diversity and trophic redundancy were lower than at the other estuaries. Among the four open estuaries, the Betsiboka and Tana (C4-dominated) had lower trophic diversity than the Zambezi and Rianila (C3-dominated), probably due to the high loads of suspended sediment, which limited the availability of aquatic sources. 4.There was seasonality in trophic structure at Ambila and Betsiboka, as trophic diversity increased and trophic redundancy decreased from the prewet to the postwet season. For Ambila, this probably resulted from the higher variability and availability of sources after the wet season, which allowed diets to diversify. For the Betsiboka, where aquatic productivity is low, this was likely due to a greater input of terrestrial material during the wet season. 5.The comparative analysis of community-wide metrics was useful to detect patterns in trophic structure and identify differences/similarities in trophic organization related to environmental conditions. However, more widespread application of these approaches across different faunal communities in contrasting ecosystems is required to allow identification of robust large-scale patterns in trophic structure. The approach used here may also find application in comparing food web organization before and after impacts or monitoring ecological recovery after rehabilitation.

Food choices that achieve calcium adequacy in older women

Aim
In a sample of older women, we assessed the proportion who met the estimated average requirement (1100 mg/day) for calcium and the dietary food choices that achieved calcium adequacy. We also assessed if the diets adequate in dietary calcium were consistent with the other dietary recommendations for health.

Methods
Baseline data from women aged 50+ years who were recruited for dietary intervention studies were included as a proxy for usual intake. Analyses of usual food and nutrient intake were derived from two 24-hour recalls.

Results
Women (n = 145) aged 50+ years (mean age 59.3 (SD 5.5) years, mean calcium intake of 815 (323) mg calcium/day) participated. Approximately one-fifth met the estimated average requirement for calcium (21%, n = 31); among this group, dairy products contributed to 61% of calcium intake (mean 2.8 (SD 1.0) servings/day). Milk contributed 33% (425 mg) of total dietary calcium. Three per cent consumed skim milk only. Both groups (calcium adequate/inadequate) exceeded the suggested dietary target (≤10%) recommended for percent energy from saturated fat, 13.4% (3.7%) and 11.7% (3.5%), respectively. In the adequate group, if skim milk replaced full-fat and reduced-fat milk, then percent energy from saturated fat would fall by 3% (from 13.4% of energy to 10.4% of energy).

Conclusions
Consumption of at least 2.8 servings/day of dairy products is likely to ensure an adequate calcium intake (>1100 mg) in women over 50 years. However, to ensure saturated fat remains at recommended levels, usual consumption of full-fat and reduced-fat milk should be replaced with skim milk.

Family food involvement and frequency of famiy dinner meals among Australian children aged 10-12 years. Cross-sectional and longitudinal associations with dietary patterns

Involvement in meal preparation and eating meals with the family are associated with better dietary patterns in adolescents, however little research has included older children or longitudinal study designs. This 3-year longitudinal study examines cross-sectional and longitudinal associations between family food involvement, family dinner meal frequency and dietary patterns during late childhood. Questionnaires were completed by parents of 188 children from Greater Melbourne, Australia at baseline in 2002 (mean age = 11.25 years) and at follow-up in 2006 (mean age = 14.16 years). Principal components analysis (PCA) was used to identify dietary patterns. Factor analysis (FA) was used to determine the principal factors from six indicators of family food involvement. Multiple linear regression models were used to predict the dietary patterns of children and adolescents at baseline and at follow-up, 3 years later, from baseline indicators of family food involvement and frequency of family dinner meals. PCA revealed two dietary patterns, labeled a healthful pattern and an energy-dense pattern. FA revealed one factor for family food involvement. Cross-sectionally among boys, family food involvement score (β = 0.55, 95% CI: 0.02, 1.07) and eating family dinner meals daily (β = 1.11, 95% CI: 0.27, 1.96) during late childhood were positively associated with the healthful pattern. Eating family dinner meals daily was inversely associated with the energy-dense pattern, cross-sectionally among boys (β = −0.56, 95% CI: −1.06, −0.06). No significant cross-sectional associations were found among girls and no significant longitudinal associations were found for either gender. Involvement in family food and eating dinner with the family during late childhood may have a positive influence on dietary patterns of boys. No evidence was found to suggest the effects on dietary patterns persist into adolescence.

Towards global benchmarking of food environments and policies to reduce obesity and diet-related non-communicable diseases : design and methods for nation-wide surveys

Introduction: 

Food references and marketing in popular magazines for children and adolescents in New Zealand. A content analysis

Food marketing is recognized as an important factor influencing children's food preferences and consumption. The purpose of this study was to examine the nature and extent of unhealthy food marketing and non-branded food references in magazines targeted at and popular among children and adolescents 10–17 years in New Zealand. A content analysis was conducted of all food references (branded and non-branded) found in the five magazines with the highest readership among 10–17 year olds, and the three magazines (of which two were already included among the five most popular magazines) targeted to 10–17 year olds. For each of the six magazines one issue per month (n = 72 issues in total) over a one-year period (December 2012–January 2014) was included. All foods referenced were classified into healthy/unhealthy according to the food-based Ministry of Health classification system. Branded food references (30% of total) were more frequent for unhealthy (43%) compared to healthy (25%) foods. Magazines specifically targeted to children and adolescents contained a significantly higher proportion of unhealthy branded food references (72%, n = 51/71) compared to the most popular magazines among children and adolescents (42%, n = 133/317), of which most were targeted to women. ‘Snack items’ such as chocolates and ice creams were marketed most frequently (n = 104; 36%), while ‘vegetables and fruits’ were marketed the least frequently (n = 9; 3%). Direct advertisements accounted for 27% of branded food references and 25% of those featured health or nutrition claims. Both branded and non-branded food references were common within magazines targeted at and popular among children and adolescents, and skewed toward unhealthy foods. This raises concerns about the effectiveness of self-regulation in marketing and emphasizes that government regulations are needed in order to curb children's current potential high exposures to unhealthy food marketing. In addition, magazine editors could take socially responsible editorial positions in regard to healthy eating.

Characterisation of lipase fatty acid selectivity using novel omega-3 pNP-acyl esters

 Lipases have applications for the industrial processing of lipids, including concentrating and/or modifying fish oil derived omega-3 fatty acids, widely used as nutritional supplement and functional food ingredients. A range of para-nitrophenol (pNP) acyl esters were synthesised as a means to rapidly screen lipases for fatty acid selectivity using spectrophotometric detection. The chosen esters were based primarily on the most abundant fatty acids present in anchovy and tuna oils. pNP derivatives of C16:1 n-7, C18:1 n-9 (OA), C18:2 n-6 (LA), C18:3 n-3 (ALA), C20:5 n-3 (EPA) and C22:6 n-3 (DHA) were synthesised. Storage stability of these pNP derivatives was shown to be at least 6 months and all pNP derivatives, including those of EPA and DHA, were shown to be stable throughout the conditions of the assay. We applied the new assay substrates for the determination of fatty acid selectivity of five widely utilised lipases. Results showed that the lipase from Candida rugosa was the most selective in terms of omega-3 specificity, preferentially hydrolysing all other medium– long chain substrates. Lipases from Rhizomucor miehei and Thermomyces lanuginosa also showed selectivity, with a significant preference for saturated fatty acids. Candida Antarctica lipase B and Aspergillus niger lipase were the least selective.

Evaluation of bread crumbs as a potential carbon source for the growth of Thraustochytrid species for oil and omega-3 production

The utilization of food waste by microorganisms to produce omega-3 fatty acids or biofuel is a potentially low cost method with positive environmental benefits. In the present study, the marine microorganisms Thraustochytrium sp. AH-2 and Schizochytrium sp. SR21 were used to evaluate the potential of breadcrumbs as an alternate carbon source for the production of lipids under static fermentation conditions. For the Thraustochytrium sp. AH-2, submerged liquid fermentation with 3% glucose produced 4.3 g/L of biomass and 44.16 mg/g of saturated fatty acids after seven days. Static fermentation with 0.5% and 1% breadcrumbs resulted in 2.5 and 4.7 g/L of biomass, and 42.4 and 33.6 mg/g of saturated fatty acids, respectively. Scanning electron microscopic (SEM) studies confirmed the growth of both strains on breadcrumbs. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy for both strains were consistent with the utilization of breadcrumbs for the production of unsaturated lipids, albeit at relatively low levels. The total lipid yield for static fermentation with bread crumbs was marginally lower than that of fermentation with glucose media, while the yield of unsaturated fatty acids was considerably lower, indicating that static fermentation may be more appropriate for the production of biodiesel than for the production of omega-3 rich oils in these strains.

Recent advances in omega-3: health benefits, sources, products and bioavailability

The joint symposium of The Omega-3 Centre and the Australasian Section American Oil Chemists Society; Recent Advances in Omega-3: Health Benefits, Sources, Products and Bioavailability, was held November 7, 2013 in Newcastle, NSW, Australia. Over 115 attendees received new information on a range of health benefits, aquaculture as a sustainable source of supply, and current and potential new and novel sources of these essential omega-3 long-chain (LC, ≥ C20) polyunsaturated fatty acid nutrients (also termed LC omega-3). The theme of "Food versus Fuel" was an inspired way to present a vast array of emerging and ground breaking Omega-3 research that has application across many disciplines. Eleven papers submitted following from the Omega-3 Symposium are published in this Special Issue volume, with topics covered including: an update on the use of the Omega-3 Index (O3I), the effects of dosage and concurrent intake of vitamins/minerals on omega-3 incorporation into red blood cells, the possible use of the O3I as a measure of risk for adiposity, the need for and progress with new land plant sources of docosahexaenoic acid (DHA, 22:6ω3), the current status of farmed Australian and New Zealand fish, and also supplements, in terms of their LC omega-3 and persistent organic pollutants (POP) content, progress with cheap carbon sources in the culture of DHA-producing single cell organisms, a detailed examination of the lipids of the New Zealand Greenshell mussel, and a pilot investigation of the purification of New Zealand hoki liver oil by short path distillation. The selection of papers in this Special Issue collectively highlights a range of forward looking and also new and including positive scientific outcomes occurring in the omega-3 field.

Does food store access modify associations between intrapersonal factors and fruit and vegetable consumption?

Background/Objectives:Existing theoretical frameworks suggest that healthy eating is facilitated by an individual's ability, motivation and environmental opportunities. It is plausible, although largely untested, that the importance of factors related to ability and motivation differ under varied environmental conditions. This study aimed to determine whether the magnitude of associations between fruit and vegetable consumption and intrapersonal factors (ability and motivation) were modified by differences in access to stores selling these items (environmental opportunities).Subjects/Methods: Cross-sectional analysis of 4335 women from socioeconomically disadvantaged neighbourhoods in the state of Victoria, Australia. Self-reported fruit and vegetable consumption was assessed against a number of ability- and motivation-related factors. To examine whether associations were modified by store access, interactions with access to supermarkets and greengrocers within 2 km of participants' households were tested.Results:Of the two factors related to ability and seven factors related to motivation, almost all were associated with fruit and vegetable consumption. In general, associations were not modified by store access suggesting that these factors were not tempered by environmental opportunities.Conclusions:This study provides little support for the hypothesis that the importance of intra-personal factors to fruit and vegetable consumption is modified by food store access. Further research on this topic is required to inform behaviour change interventions.European Journal of Clinical Nutrition advance online publication, 21 January 2015; doi:10.1038/ejcn.2014.287.

Complex coacervation with whey protein isolate and gum arabic for the microencapsulation of omega-3 rich tuna oil.

Tuna oil rich in omega-3 fatty acids was microencapsulated in whey protein isolate (WPI)-gum arabic (GA) complex coacervates, and subsequently dried using spray and freeze drying to produce solid microcapsules. The oxidative stability, oil microencapsulation efficiency, surface oil and morphology of these solid microcapsules were determined. The complex coacervation process between WPI and GA was optimised in terms of pH, and WPI-to-GA ratio, using zeta potential, turbidity, and morphology of the microcapsules. The optimum pH and WPI-to-GA ratio for complex coacervation was found to be 3.75 and 3 : 1, respectively. The spray dried solid microcapsules had better stability against oxidation, higher oil microencapsulation efficiency and lower surface oil content compared to the freeze dried microcapsules. The surface of the spray dried microcapsules did not show microscopic pores while the surface of the freeze dried microcapsules was more porous. This study suggests that solid microcapsules of omega-3 rich oils can be produced using WPI-GA complex coacervates followed by spray drying and these microcapsules can be quite stable against oxidation. These microcapsules can have many potential applications in the functional food and nutraceuticals industry.