Particle emission factors during cooking activities

Exposure to particles emitted by cooking activities may be responsible for a variety of respiratory health effects. However, the relationship between these exposures and their subsequent effects on health cannot be evaluated without understanding the properties of the emitted aerosol or the main parameters that influence particle emissions during cooking. Whilst traffic-related emissions, stack emissions and ultrafine particle concentrations (UFP, diameter < 100 nm) in urban ambient air have been widely investigated for many years, indoor exposure to UFPs is a relatively new field and in order to evaluate indoor UFP emissions accurately, it is vital to improve scientific understanding of the main parameters that influence particle number, surface area and mass emissions. The main purpose of this study was to characterise the particle emissions produced during grilling and frying as a function of the food, source, cooking temperature and type of oil. Emission factors, along with particle number concentrations and size distributions were determined in the size range 0.006-20 m using a Scanning Mobility Particle Sizer (SMPS) and an Aerodynamic Particle Sizer (APS). An infrared camera was used to measure the temperature field. Overall, increased emission factors were observed to be a function of increased cooking temperatures. Cooking fatty foods also produced higher particle emission factors than vegetables, mainly in terms of mass concentration, and particle emission factors also varied significantly according to the type of oil used.

Confidence to cook vegetables and the buying habits of Australian households

Cooking skills are emphasized in nutrition promotion but their distribution among population subgroups and relationship to dietary behavior is researched by few population-based studies. This study examined the relationships between confidence to cook, sociodemographic characteristics, and household vegetable purchasing. This cross-sectional study of 426 randomly selected households in Brisbane, Australia, used a validated questionnaire to assess household vegetable purchasing habits and the confidence to cook of the person who most often prepares food for these households. The mutually adjusted odds ratios (ORs) of lacking confidence to cook were assessed across a range of demographic subgroups using multiple logistic regression models. Similarly, mutually adjusted mean vegetable purchasing scores were calculated using multiple linear regression for different population groups and for respondents with varying confidence levels. Lacking confidence to cook using a variety of techniques was more common among respondents with less education (OR 3.30; 95% confidence interval [CI] 1.01 to 10.75) and was less common among respondents who lived with minors (OR 0.22; 95% CI 0.09 to 0.53) and other adults (OR 0.43; 95% CI 0.24 to 0.78). Lack of confidence to prepare vegetables was associated with being male (OR 2.25; 95% CI 1.24 to 4.08), low education (OR 6.60; 95% CI 2.08 to 20.91), lower household income (OR 2.98; 95% CI 1.02 to 8.72) and living with other adults (OR 0.53; 95% CI 0.29 to 0.98). Households bought a greater variety of vegetables on a regular basis when the main chef was confident to prepare them (difference: 18.60; 95% CI 14.66 to 22.54), older (difference: 8.69; 95% CI 4.92 to 12.47), lived with at least one other adult (difference: 5.47; 95% CI 2.82 to 8.12) or at least one minor (difference: 2.86; 95% CI 0.17 to 5.55). Cooking skills may contribute to socioeconomic dietary differences, and may be a useful strategy for promoting fruit and vegetable consumption, particularly among socioeconomically disadvantaged groups.

Should cooking be a dietetic competency?

Aim:  There are issues surrounding the apparent decline and devaluing of cooking skills in the population, potential health impacts and the role of dietitians. The present paper aims to outline several arguments and raise questions on the relationship between cooking and dietetics.---------- Methods:  Evidence from dietetics and nutrition journals and other sources is used to develop positions for dietetics and its relationship to cooking and cooking skills. ---------- Results:  The historical relationship between dietetics and home economics has seen dietetics professionally distance itself by its scientific education on food and nutrition, rather than actual involvement with cooking. In pursuing this rational scientific approach there are concerns that dietitians have inadvertently supported the growth of the functional and convenience food market, particularly given the demise of home economics as a skill-based curricula in schools in several states. There is a need to consider what role cooking skills could have in dietetics training as a professional competency for practice, particularly for public health interventions. This is in the light of Commonwealth government funding that is legitimising cooking skill interventions as a policy response to obesity. There may be a role for dietitians to develop partnerships and train a new professional category or paraprofessionals and/or peer educators to deliver cooking skill interventions. ---------- Conclusion:  There is a need for research on dietitian's views and use of cooking skill interventions. This would help answer whether we should consider cooking and cooking skills as part of our professional practice and whether cooking should be a dietetic competency.

What's cooking for dietetics? A review of the literature

Aim: There has been no systematic research on the role of cooking skills for improving dietary intakes in Australia. Cooking skills are proposed to be declining and/or being devalued. If cooking skills have been devalued and declining, then what evidence is there for this decline and what impact might this have on dietary intakes? The aim of the present paper is to explore these assumptions with particular reference to Australia. The objectives of the present paper are to define the terms cooking and cooking skills, discuss evidence on levels of cooking skills in Australia and describe the evidence linking cooking skills to dietary intakes.---------- Methods: A review of the peer-reviewed literature using multiple databases from 1990 to September 2009.---------- Results: Cooking skills are complex and require a range of processes for people to develop efficiency or confidence in food preparation. There is little evidence on the level of cooking skills in the Australian population and how this relates to dietary intakes. The Australian Bureau of Statistic’s latest Time Use Survey and Household Expenditure Survey suggest that cooking is still a gendered activity and that the time devoted to cooking has changed little in the past 15 years, but there is an increasing use of foods prepared outside the home.---------- Conclusion: Further research is required to examine the prevalence of different types and levels of cooking skills in Australia as well as their potential effects on dietary intakes. Dietitians need evidence about the level of cooking skills people require for healthy dietary intakes.

Investigation into the introduction of clonal strains of Pseudomonas aeruginosa to the cystic fibrosis population by consumption of raw salad vegetables

Most salad vegetables are eaten fresh by consumers. However, raw vegetables may pose a risk of transmitting opportunistic bacteria to immunocompromised people, including cystic fibrosis (CF) patients. In particular, CF patients are vulnerable to chronic Pseudomonas aeruginosa lung infections and this organism is the primary cause of morbidity and mortality in this group. Clonal variants of P. aeruginosa have been identified as emerging threats to people afflicted with CF; however it has not yet been proven from where these clones originate or how they are transmitted. Due to the organisms‟ aquatic environmental niche, it was hypothesised that vegetables may be a source of these clones. To test this hypothesis, lettuce, tomatoes, mushrooms and bean sprout packages (n = 150) were analysed from a green grocer, supermarket and farmers‟ market within the Brisbane region, availability permitting. The internal and external surfaces of the vegetables were separately analysed for the presence of clonal strains of P. aeruginosa using washings and homogenisation techniques, respectively. This separation was in an attempt to establish which surface was contaminated, so that recommendations could be made to decrease or eliminate P. aeruginosa from these foods prior to consumption. Soil and water samples (n = 17) from local farms were also analysed for the presence of P. aeruginosa. Presumptive identification of isolates recovered from these environmental samples was made based on growth on Cetrimide agar at 42°C, presence of the cytochrome-oxidase enzyme and inability to ferment lactose. P. aeruginosa duplex real-time polymerase chain reaction assay (PAduplex) was performed on all bacterial isolates presumptively identified as P. aeruginosa. Enterobacterial repetitive intergenic consensus strain typing PCR (ERIC-PCR) was subsequently performed on confirmed bacterial isolates. Although 72 P. aeruginosa were isolated, none of these proved to be clonal strains. The significance of these findings is that vegetables may pose a risk of transmitting sporadic strains of P. aeruginosa to people afflicted with CF and possibly, other immunocompromised people.

Study of tissue damage during mechanical peeling of tough skinned vegetables

Peeling is an essential phase of post harvesting and processing industry; however the undesirable losses and waste rate that occur during peeling stage are always the main concern of food processing sector. There are three methods of peeling fruits and vegetables including mechanical, chemical and thermal, depending on the class and type of fruit. By comparison, the mechanical method is the most preferred; this method keeps edible portions of produce fresh and creates less damage. Obviously reducing material losses and increasing the quality of the process has a direct effect on the whole efficiency of food processing industry which needs more study on technological aspects of this industrial segment. In order to enhance the effectiveness of food industrial practices it is essential to have a clear understanding of material properties and behaviour of tissues under industrial processes. This paper presents the scheme of research that seeks to examine tissue damage of tough skinned vegetables under mechanical peeling process by developing a novel FE model of the process using explicit dynamic finite element analysis approach. In the proposed study a nonlinear model which will be capable of simulating the peeling process specifically, will be developed. It is expected that unavailable information such as cutting force, maximum shearing force, shear strength, tensile strength and rupture stress will be quantified using the new FEA model. The outcomes will be used to optimize and improve the current mechanical peeling methods of this class of vegetables and thereby enhance the overall effectiveness of processing operations. Presented paper aims to review available literature and previous works have been done in this area of research and identify current gap in modelling and simulation of food processes.

Utilization of bio-oil for cooking and lighting

Among the available alternative sources of energy in Bangladesh bio-oil is recognized to be a promising alternative energy source. Bio-oil can be extracted by pyrolysis as well as expelling or solvent extractionmethod. In these days bio-oil is merely used in vehicles and power plants after some up gradation .However, it is not used for domestic purposes like cooking and lighting due to its high density and viscosity. This paper outlines the design of a gravity stove to use high dense and viscous bio-oil for cooking purpose. For this, Pongamia pinnata (karanj) oil extracted by solvent extraction method is used as fuel fed under gravity force. Efficiency of gravity stove with high dense and viscous bio-oil (karanj) is 11.81% which of kerosene stove is 17.80% also the discharge of karanj oil through gravity stove is sufficient for continuous burning. Thus, bio-oil can be effective replacement of kerosene for domestic purposes.

Study of mechanical deformations on tough skinned vegetables during mechanical peeling process

Peeling is an essential phase of post harvesting and processing industry; however undesirable processing losses are unavoidable and always have been the main concern of food processing sector. There are three methods of peeling fruits and vegetables including mechanical, chemical and thermal, depending on the class and type of fruit. By comparison, the mechanical methods are the most preferred; mechanical peeling methods do not create any harmful effects on the tissue and they keep edible portions of produce fresh. The main disadvantage of mechanical peeling is the rate of material loss and deformations. Obviously reducing material losses and increasing the quality of the process has a direct effect on the whole efficiency of food processing industry, this needs more study on technological aspects of these operations. In order to enhance the effectiveness of food industrial practices it is essential to have a clear understanding of material properties and behaviour of tissues under industrial processes. This paper presents the scheme of research that seeks to examine tissue damage of tough skinned vegetables under mechanical peeling process by developing a novel FE model of the process using explicit dynamic finite element analysis approach. A computer model of mechanical peeling process will be developed in this study to stimulate the energy consumption and stress strain interactions of cutter and tissue. The available Finite Element softwares and methods will be applied to establish the model. Improving the knowledge of interactions and involves variables in food operation particularly in peeling process is the main objectives of the proposed study. Understanding of these interrelationships will help researchers and designer of food processing equipments to develop new and more efficient technologies. Presented work intends to review available literature and previous works has been done in this area of research and identify current gap in modelling and simulation of food processes.

Utilization of bio-oil for cooking and lighting

Considerable attention has been given to development of renewable energy due to imminent depletion of fossil fuels and environmental concerns over global warming. Therefore, it is necessary to find out all the available alternative sources of energy immediately to meet the increasing energy demand of Bangladesh. Among the available alternative sources of energy in Bangladesh bio-oil is recognized to be a promising alternative energy source. In these days bio-oil is merely used in vehicles and power plants after some up gradation .However, it is not used for domestic purposes like cooking and lighting due to it’s high density and viscosity. A gravity stove is designed to use this high dense and viscous bio-oil for cooking purpose. Efficiency of gravity stove with high dense and viscous bio-oil (karanj) is 11.81% which of kerosene stove is 17.80% also the discharge of karanj oil through gravity stove is sufficient for continuous burning.

Comparing the availability, price, variety and quality of fruits and vegetables across retail outlets and by area level socioeconomic position

Abstract Objective: To explore whether area-level socioeconomic position or the form of retail stream (conventional versus farmers’ market) are associated with differences in the price, availability, variety and quality of a range of fresh fruit and vegetables. Design: A multi-site cross-sectional pilot study of farmers’ markets, supermarkets and independent fruit and vegetable retailers. Each was surveyed to assess the price, availability, variety and quality of 15 fruit and 18 vegetable items. Setting: Retail outlets were located in South-East Queensland. Subjects: Fifteen retail outlets were surveyed (five of each retail stream). Results: Average basket prices were not significantly different across the socioeconomic spectrum however prices in low socioeconomic areas were cheapest. Availability, variety, and quality did not differ across levels of socioeconomic position however the areas with the most socioeconomic disadvantage scored poorest for quality and variety. Supermarkets had significantly better fruit and vegetable availability than farmers’ markets however price, variety and quality scores were not different across retail streams. Results demonstrate a trend to fruit and vegetable prices being more expensive at farmers’ markets, with the price of the Fruit basket being significantly greater at the organic farmer’s market compared with the non-organic farmers’ markets. Conclusions: Neither area-level socioeconomic position nor the form of retail stream was significantly associated with differences in the availability, price, variety and quality of fruit and vegetables, except for availability which was higher in supermarkets than farmers’ markets. Further research is needed to determine what role farmers’ markets can play in affecting fruit and vegetable intake.

'Savoir fare': are cooking skills a new morality

There has been a recent surge of interest in cooking skills in a diverse range of fields, such as health, education and public policy. There appears to be an assumption that cooking skills are in decline and that this is having an adverse impact on individual health and well-being, and family wholesomeness. The problematisation of cooking skills is not new, and can be seen in a number of historical developments that have specified particular pedagogies about food and eating. The purpose of this paper is to examine pedagogies on cooking skills and the importance accorded them. The paper draws on Foucault’s work on governmentality. By using examples from the USA, UK and Australia, the paper demonstrates the ways that authoritative discourses on the know how and the know what about food and cooking – called here ‘savoir fare’ – are developed and promulgated. These discourses, and the moral panics in which they are embedded, require individuals to make choices about what to cook and how to cook, and in doing so establish moral pedagogies concerning good and bad cooking. The development of food literacy programmes, which see cooking skills as life skills, further extends the obligations to ‘cook properly’ to wider populations. The emphasis on cooking knowledge and skills has ushered in new forms of government, firstly, through a relationship between expertise and politics which is readily visible through the authority that underpins the need to develop skills in food provisioning and preparation; secondly, through a new pluralisation of ‘social’ technologies which invites a range of private-public interest through, for example, television cooking programmes featuring cooking skills, albeit it set in a particular milieu of entertainment; and lastly, through a new specification of the subject can be seen in the formation of a choosing subject, one which has to problematise food choice in relation to expert advice and guidance. A governmentality focus shows that as discourses develop about what is the correct level of ‘savoir fare’, new discursive subject positions are opened up. Armed with the understanding of what is considered expert-endorsed acceptable food knowledge, subjects judge themselves through self-surveillance. The result is a powerful food and family morality that is both disciplined and disciplinary.

Recipe for success : cooking up a storm in the technology classroom

Ingredients: - 1 cup Vision - 100ml ‘Real World’ Application - 100ml Unit Structure/Organisation - 100ml Student-centric Approach [optional: Add Social Media/Popular Culture for extra goodness] - Large Dollop of Passion + Enthusiasm - Sprinkle of Approachability Mix all ingredients well. Cover and leave to rise in a Lecture Theatre for 1.5 hours. Cook in a Classroom for 1.5 hours. Garnish with a dash of Humour before serving. Serves 170 Students

Cooking enhances but the degree of ripeness does not affect provitamin A carotenoid bioavailability from bananas

Banana is a staple crop in many regions where vitamin A deficiency is prevalent, making it a target for provitamin A biofortification. However, matrix effects may limit provitamin A bioavailability from bananas. The retinol bioefficacies of unripe and ripe bananas (study 1A), unripe high-provitamin A bananas (study 1B), and raw and cooked bananas (study 2) were determined in retinol-depleted Mongolian gerbils (n = 97/study) using positive and negative controls. After feeding a retinol-deficient diet for 6 and 4 wk in studies 1 and 2, respectively, customized diets containing 60, 30, or 15% banana were fed for 17 and 13 d, respectively. In study 1A, the hepatic retinol of the 60% ripe Cavendish group (0.52 ± 0.13 μmol retinol/liver) differed from baseline (0.65 ± 0.15 μmol retinol/liver) and was higher than the negative control group (0.39 ± 0.16 μmol retinol/liver; P < 0.0065). In study 1B, no groups differed from baseline (0.65 ± 0.15 μmol retinol/liver; P = 0.20). In study 2, the 60% raw Butobe group (0.68 ± 0.17 μmol retinol/liver) differed from the 60% cooked Butobe group (0.87 ± 0.24 μmol retinol/liver); neither group differed from baseline (0.80 ± 0.27 μmol retinol/liver; P < 0.0001). Total liver retinol was higher in the groups fed cooked bananas than in those fed raw (P = 0.0027). Body weights did not differ even though gerbils ate more green, ripe, and raw bananas than cooked, suggesting a greater indigestible component. In conclusion, thermal processing, but not ripening, improves the retinol bioefficacy of bananas. Food matrix modification affects carotenoid bioavailability from provitamin A biofortification targets.

Children exposure assessment to ultrafine particles and black carbon: The role of transport and cooking activities

An accurate evaluation of the airborne particle dose-response relationship requires detailed measurements of the actual particle concentration levels that people are exposed to, in every microenvironment in which they reside. The aim of this work was to perform an exposure assessment of children in relation to two different aerosol species: ultrafine particles (UFPs) and black carbon (BC). To this purpose, personal exposure measurements, in terms of UFP and BC concentrations, were performed on 103 children aged 8-11 years (10.1 ± 1.1 years) using hand-held particle counters and aethalometers. Simultaneously, a time-activity diary and a portable GPS were used to determine the children’s daily time-activity pattern and estimate their inhaled dose of UFPs and BC. The median concentration to which the study population was exposed was found to be comparable to the high levels typically detected in urban traffic microenvironments, in terms of both particle number (2.2×104 part. cm-3) and BC (3.8 μg m-3) concentrations. Daily inhaled doses were also found to be relatively high and were equal to 3.35×1011 part. day-1 and 3.92×101 μg day-1 for UFPs and BC, respectively. Cooking and using transportation were recognized as the main activities contributing to overall daily exposure, when normalized according to their corresponding time contribution for UFPs and BC, respectively. Therefore, UFPs and BC could represent tracers of children exposure to particulate pollution from indoor cooking activities and transportation microenvironments, respectively.