Bayesian sequential D-D optimal model-robust designs.

Alphabetic optimal design theory assumes that the model for which the optimal design is derived is usually known. However in real-life applications, this assumption may not be credible, as models are rarely known in advance. Therefore, optimal designs derived under the classical approach may be the best design but for the wrong assumed model. In this paper, we extend Neff's (1996) Bayesian two-stage approach to design experiments for the general linear model when initial knowledge of the model is poor. A Bayesian optimality procedure that works well under model uncertainty is used in the first stage and the second stage design is then generated from an optimality procedure that incorporates the improved model knowledge from the first stage. In this way, a Bayesian D-D optimal model robust design is developed. Results show that the Bayesian D-D optimal design is superior in performance to the classical one-stage D-optimal and the one-stage Bayesian D-optimal designs. We also investigate through a simulation study the ratio of sample sizes for the two stages and the minimum sample size desirable in the first stage.Applications; D-D optimality; Knowledge; Model; Two-stage procedure; Posterior probabilities;

An Appraisal of The Small-Scale Agroprocessing Sector in Rodrigues – Part 2: Product Marketing, Training Programmes and Awareness of Support Services

This second and final paper on the agroprocessing sector in Rodrigues dealswith the marketing of agroprocessed products, the relevance of past trainingprogrammes, future training needs in the sector and end-users’ awareness ofsupport services. 119 producers were interviewed using a structured questionnaire. The survey indicated that the products are mostly sold directly to the consumers (69%) by the processors, either along the roadside or market stalls. The products are mainly advertised through word-ofmouth. Most of them do not keep financial, production and sale records and do not calculate their cost of production. 75% of them fix the selling price by adding a mark-up on their perceived cost of production, while some 20.4% rely on the prices set by their competitors. 68% of the respondents An Appraisal of The Small Scale Agroprocessing Sector in Rodrigues- Part 2: Product Marketing, Training Programmes and Awareness of Support Services 59 have followed a training programme and 80% of them find it to bebeneficial. There is a high demand for training in the following areas; food preservation techniques, packaging, food labelling, food safety and quality,business management and marketing skills. Several support institutionsprovide technical information, financial assistance and training to the agroprocessors but their activities are not properly coordinated. Specificrecommendations regarding improved marketing strategies, effective training programmes and support services are made for boosting the agroprocessing sector.Keywords: Rodrigues, small-scale agroprocessors, marketing, training,support institutions

Effects of cutting shapes and thicknesses on the quality of minimally processed pineapple (Ananas comosus), cv. 'Queen Victoria'

Cutting shape and size are physical factors that influence the keeping quality of minimally processed fruits and vegetables. Since these factors have not been studied as determinants of the keeping quality of minimally processed pineapples (MPP) cv. ‘Queen Victoria’, this study was conducted. A 2 x 2 factorial treatment structure laid on a randomized block design (RBD) was used. The treatments, which were blocked by days, were combinations of two cutting shapes (slices and chunks) and two thicknesses (5 mm and 10 mm). Pineapples of 25 - 50% ripeness were minimally processed to give rise to the treatments, which were then vacuum-packed at 47.5 kPa in laminated Low Density Polyethylene (LDPE) vacuum bags and stored at 4 ± 10C for 12 days. Quality changes were evaluated at three-day intervals over a storage period of 12 days. Translucency score was evaluated by comparison method against standard colour charts. Electrical conductivity of leachate (ECL), firmness and pH were measured instrumentally. Ascorbic acid (AA) content was determined by titration with dichlorophenolindophenol (DCPIP) dye. Yeasts and moulds counts (YMC) were also enumerated using the classical standard method. Data were analysed using analysis of variance (ANOVA), and sum of squares due to treatment were split into main effect cutting shape, main effect thickness and interaction effect. All the keeping quality attributes of the MPP were significantly affected by storage time (p<0.001). Cutting shape also significantly affected translucency score (p<0.01), firmness (p<0.01) and YMC (p<0.01). Slices were firmer and had the lowest translucency score and minimized fungal growth as opposed to chunks. No significant interaction effect (p>0.05) was observed between cutting shapes and thicknesses on translucency score, firmness and YMC of the MPP. However, a significant interaction effect was noted between these two variables on ECL (p<0.05) and AA content (p<0.001). A thickness of 10 mm exhibited lower translucency score, higher ECL, reduced firmness and lower AA losses. pH was not significantly affected (p>0.05) by cutting shapes and thicknesses. Ten-mm slices maintained all the above-stated quality parameters, except ECL and pH, when stored at 4 ± 10C for 12 days

An Assessment of the Nutritional Knowledge and Eating Habits of Vegetarians in Mauritius

The objectives of this paper were to identify the nutritional knowledge and beliefs of vegetarians, assess their eating habits and also investigate on the reasons why they have adopted a vegetarian diet. A survey questionnaire was adopted for the study. A quota sampling of 100 vegetarians from four different age groups was targeted and a 24-hour dietary recall was used to analyze the eating habits of a sub-sample of twenty respondents. The respondents were found to be mostly of Hindu origin (85%) and the majority were lacto vegetarians who preferred a meat-free diet on grounds of religious beliefs, dislike of animal flesh as well as for ethical reasons respectively. They are knowledgeable about the importance of micro and macro-nutrients in the vegetarian diet, but the food recall also revealed that only three out of the twenty respondents were consuming balanced meals that is they were having foods from the three food groups namely ‘food for energy’, ‘food for growth’ and ‘food for health’. The mismatch between theoretical knowledge and practice was revealed clearly in the sense that 96 % of the respondents are aware of the concept of balanced diet however; this was not put into practice when analyzing the meals that were consumed. This calls for dietary guidelines and food guide models which are specific to vegetarians as the Mauritian population comprises mostly of Hindus who follow vegetarian diets.Keywords: Vegetarian diet, Nutrition, eating habits and knowledg

Nutritional Status of School Children Aged 8-12 Years in Deprived Areas of Mauritius

This study investigated the nutritional status of school children in deprived areas of Mauritius and determined whether specific socio-economic factors were associated with poor nutritional status among children. A cross-sectional survey was conducted among 240 primary school children aged 8-12 years old. Out of 27 schools located in the deprived regions of Mauritius, eight of them were selected for the study. The data collection tools included a questionnaire, anthropometric measurements (weight and height) and a 24-hour dietary recall. A questionnaire was used to gather information on the socioeconomic profile of the children and their eating patterns. The Centre for Disease Control (CDC) BMI-for-age and stature-for-age percentiles were used to identify children who were stunted (<5th percentile stature-for-age), underweight (< 5th BMI-for age percentile), overweight (85th to 95th percentile BMI-for age) or obese (≥95th percentile BMI-for-age). Findings revealed that the main meals taken by the children included breakfast, lunch and dinner. Ninety two percent of the children mentioned taking breakfast in the morning; the most commonly consumed food commodities being bread, margarine, cheese, jam and tea; milk, yoghurt, fruits or fruit juice were rarely consumed. Packed lunches consisted mainly of eggs and convenience foods such as sausages without any vegetables. Poor snacking habits, that is, high consumption of salty corn-based snacks, were identified among these children. Age of school children was significantly associated (p<0.05) with the amount of money spent on snacks at school. Anthropometric measurements revealed the prevalence of both undernutrition and overnutrition among the children. Thirty seven per cent of the children were underweight, four per cent were overweight, three per cent were obese and there were no cases of stunting. The study findings indicate that the children are being fed the wrong kinds of foods or the wrong proportions. Thus, there is a need for local education and health authorities to develop nutrition education programmes that are contextually sensitive to specifically target school children and parents in deprived areas of Mauritius.Key words: Nutritional status, deprived children, Mauritiu

An assessment of the hygiene level in animal product processing plants in Mauritius

A study was carried out to assess hygiene level in the 20 local animal product processing plants.   Questionnaire based interviews with managers and food handlers gave an overview of perception of hygiene and practices related to it. Checklists using a scoring system, were designed for objective hygiene inspection. According to the checklist, plants and food handlers were classified as “outstanding”, “good”, “average”, “poor” and “very poor”. The plants were mainly large to medium scale and sold their products locally. Six out of the 20 plants had outstanding or good hygiene level as they satisfied most hygiene parameters. The remaining 14 plants had average to very poor hygiene level. This study showed that factors like hygiene training, hazard control systems and other good manufacturing practices affect the hygiene status of a plant. Major problem areas identified were waste disposal, provision of facilities to staff, hazard control, training in hygiene,  cleaning  frequency and lack of mandatory control. These could represent hazard to public health and lead to  financial losses. Some recommendations have been formulated at the industry’s level, at the institutional level and at the consumers’ level.Keywords: Hygiene, animal product processing plants, checklist

Understanding the management practices of animal manure and associated risks of transference of bacterial pathogens to crop vegetables

Manure is commonly used in agricultural production in Mauritius, but little is documented on the local management practices. Animal manure, in particular, is a livestock waste that harbors enteric microorganisms which are potentially pathogenic to humans. The objectives of the study were therefore (i) to shed light on the management practices of manure among cattle and poultry farmers  (manure producers) and carrot and lettuce growers (manure end-users) and any associated health risks and (ii) to determine the prevalence of human pathogens (diarrheagenic Escherichia coli, Salmonella, Listeria monocytogenes and Clostridium perfringens) in manure collected from farmers, vegetable crops fertilized with manure as well as manure-amended soil (MAS) used in crop cultivation. A survey was conducted through in-depth interviews with 16 producers and 36 end-users to gather data on their MMP and their  perception of the health risks associated with manure handling. Samples of manure, MAS and vegetables were also microbiologically analyzed to enumerate and/or detect pathogens. Findings revealed that cattle and poultry manure was an important resource for many small-holder vegetable farmers in Mauritius. The manure distributors or end users had no negative perception of the use of untreated manure for vegetable cultivation and were generally unaware of any biosecurity risks arising from the improper handling or subsequent use of untreated manure. Microbiological analyses however showed that 100% of manure samples collected from cattle farms and 58% of the poultry litter samples tested positive for pathogenic E. coli with population ranging from 3.3 to 6.5 Log CFU/g. Manure-borne pathogens were generally undetectable in the analyzed vegetables hence indicating a low risk of foodborne infections. However, the systematic presence of pathogenic E. coli in cattle manure and frequent occurrence in poultry litter clearly point to a need for creating greater awareness amongst farmers on the occupational health risks associated with handling of raw or inadequately decomposed manure. This study therefore points to the health risks associated with enteric pathogens present in raw or untreated raw manure in Mauritius. Key words: Manure Management, Pathogens, E. coli, Salmonella, Cattle, Poultry, Carrot, Lettuce, Mauritiu

Effects of adding cellulose on rheological characteristics of wheat flour dough and on bread quality

Several studies have associated the consumption of dietary fibre with positive health effects and as a result a wide array of fibre ingredients has been developed to be included as part of formulation of functional food. Powdered cellulose is one type of fibre ingredient that is finding wide application in food, mainly in functional bread, either to increase level of fibre or to reduce calorific value. However, the inclusion of fibre in a formulation will inevitably bring about certain changes to the product. This current study investigated the effects of adding different levels (2, 4 and 6 %) of powdered cellulose on the rheological properties of wheat dough and bread qualities. The main dough characteristics assessed were farinograph water absorption, resistance and extensibility; while bread was evaluated for volume, weight, crumb softness and nutritional values (level of insoluble dietary fibre and calorie content). The bread qualities of cellulose-added bread were compared to those of brown bread. Findings revealed that water absorption of the dough and its stability against over-mixing increased significantly (P<0.05) with increasing level of powdered cellulose. Although the dough became more resistant, it lost extensibility; and thus bread of smaller volume was observed, with a decrease of about 200 cm3 at 6 % level cellulose, compared to plain bread. Cellulose-added bread was slightly heavier than plain bread and brown bread by about 5 – 15 grams. At 4 and 6 % level of fibre, bread had softer crumbs compared to both plain white bread and brown bread. With 6 % cellulose, the level of insoluble dietary fibre was 13.8 %, as compared to 6 % in plain bread and 13.1 % in brown bread. At 6 % cellulose there was a decrease of 77kcal and 47kcal compared to plain and brown bread respectively. Addition of cellulose at 2 and 4% gave bread with larger volume without improving the nutritional characteristics. At 6 % level of cellulose, bread had almost same level of insoluble dietary fibre than that of brown bread, but still offering better quality in terms of volume, weight, colour and texture compared to the brown bread. Therefore addition of powdered cellulose at level 6 % was found to be most appropriate for the purpose of functional bread.Keywords: Cellulose, rheology, flour, bread, insoluble fibre, calori

Hormonal Regulation Of Sex Expression Of Two Local Cultivators Of Cucurbits

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NUTRITIONAL STATUS OF SCHOOL CHILDREN AGED 8-12 YEARS IN DEPRIVED AREAS OF MAURITIUS

ABSTRACT This study investigated the nutritional status of school children in deprived areas of Mauritius and determined whether specific socio-economic factors were associated with poor nutritional status among children. A cross-sectional survey was conducted among 240 primary school children aged 8-12 years old. Out of 27 schools located in the deprived regions of Mauritius, eight of them were selected for the study. The data collection tools included a questionnaire, anthropometric measurements (weight and height) and a 24-hour dietary recall. A questionnaire was used to gather information on the socioeconomic profile of the children and their eating patterns. The Centre for Disease Control (CDC) BMI-for-age and stature-for-age percentiles were used to identify children who were stunted (<5 th percentile stature-for-age), underweight (< 5 th BMI-for age percentile), overweight (85 th to 95 th percentile BMI-for age) or obese (≥95 th percentile BMI-for-age). Findings revealed that the main meals taken by the children included breakfast, lunch and dinner. Ninety two percent of the children mentioned taking breakfast in the morning; the most commonly consumed food commodities being bread, margarine, cheese, jam and tea; milk, yoghurt, fruits or fruit juice were rarely consumed. Packed lunches consisted mainly of eggs and convenience foods such as sausages without any vegetables. Poor snacking habits, that is, high consumption of salty corn-based snacks, were identified among these children. Age of school children was significantly associated (p<0.05) with the amount of money spent on snacks at school. Anthropometric measurements revealed the prevalence of both undernutrition and overnutrition among the children. Thirty seven per cent of the children were underweight, four per cent were overweight, three per cent were obese and there were no cases of stunting. The study findings indicate that the children are being fed the wrong kinds of foods or the wrong proportions. Thus, there is a need for local education and health authorities to develop nutrition education programmes that are contextually sensitive to specifically target school children and parents in deprived areas of Mauritius