Seila Sar

The importance of amylose and amylopectin fine structures for starch digestibility in cooked rice grains

Statistically and causally meaningful relationships are established between starch molecular structures (obtained by size-exclusion chromatography, proton NMR and multiple-angle laser light scattering) and digestibility of cooked rice grains (measured by in vitro digestion). Significant correlations are observed between starch digestion rate and molecular structural characteristics, including fine structures of the distributions of branch (chain) lengths in both amylose and amylopectin. The in vitro digestion rate tends to increase with longer amylose branches and smaller ratios of long amylopectin and long amylose branches to short amylopectin branches, although the statistical analyses show that further data are needed to establish this unambiguously. These new relationships between fine starch structural features and digestibility of cooked rice grains are mechanistically reasonable, but suggestive rather than statistically definitive.

Effects of rice variety and growth location in Cambodia on grain composition and starch structure

The effects of variety and growth location on grain composition and starch structures were investigated using three rice (Oryza sativa L.) cultivars (Phka Romduol, Sen Pidao and IR66) with different amylose contents. All the three cultivars were planted in three different agro-climatic zones (Phnom Penh, Coastal and Plateau) of Cambodia. The protein content of polished grains increased when rice was planted at a location with higher average temperature, but their lipid content decreased. The amylose content and degree of branching were not greatly affected by the minor temperature differences among the growing locations. Starch fine structures characterized by the chain-length distribution were significantly different among the cultivars, but not significantly among different locations. The results suggested that protein and lipid biosyntheses were more sensitive to the environmental temperature than that of starch in rice grains.

Estimated effects of white rice consumption and rice variety selection on incidence of type 2 diabetes in Cambodia

OBJECTIVE Rice consumption patterns are considered an important risk factor for diabetes in many countries. The present study aimed to model the impact of a shift in consumption of white rice from current to appropriately reduced levels and a shift in rice variety from one with a high glycaemic index to one with a low glycaemic index, on the burden of type 2 diabetes in Cambodia. DESIGN Prevent Plus software was used to model the impact of selected changes to white rice consumption on the burden of type 2 diabetes. Data used for modelling included: demographic projections, relative risk estimates for white rice consumption and diabetes, diabetes incidence, rice type and quantities consumed. The 10-year projections were based on different scenarios of changes in risk factors. RESULTS With no intervention, 10-year projections showed that total new diabetes cases will increase from 11 315 (9·1 per 10 000 person-years) for the year 2011 to 14 852 new cases (12·4 per 10 000 person-years) in 2020. However, this increase will be reduced by 27 % (average across 10 years) with a change in rice variety from Phka Rumdual to IR66 and by 26 % (average across 10 years) with a 25 % reduction in quantity from current consumption levels. CONCLUSIONS Changing rice consumption patterns has potential for an important impact on diabetes risk, with a change of rice variety having a similar impact on the burden of diabetes in communities consuming rice with a high glycaemic index as a 25 % reduction in the quantity of rice consumed. Similar effects are likely for other countries with rice as a staple food, diversity in rice varieties and high incidence of diabetes.

Health Implications of Rice Cultivar Diversity and Carbohydrate Digestibilty in Cambodia

Abstract of paper that presented at 20th International Congress of Nutrition, Granada, September 2013.Background and Objectives: Indonesia is one of the countries facing nutrition transition with an increased proportion of the middle-class population. Few studies explored young child feeding practice amongst middle class families in developing countries. This study aims to assess child feeding practices and their associations with child nutritional status in urban area of Indonesia. Methods: The study was designed as a mixed-method study in an urban middle-class community, comprising of a qualitative study amongst 26 families of young children and a case-control study involving 288 (109 cases and 179 controls) children aged 12-36 months. Cases were mild to moderately underweight children, while controls were normal weight children. The data collection methods consisted of in-depth interview for the qualitative phase and anthropometry measurements, structured interviews pertaining to child feeding practices and 24-hours recall for the quantitative phase. Results: The qualitative study suggested that mothers appeared to have positive attitude and were familiar with many brands of toddler formula milk. Mothers reported challenges in encouraging their children to eat and relied on formula milk to increase child’s food intake.The results of the case-control study showed that only 10.4% children received six-month exclusive breastfeeding and there was a significantly higher proportion of control than case children who were offered formula milk within their first month of life. Almost all children (91.7%, CI = 87.7 – 94.5) had low dietary diversity (consumed 1-3 food groups) in the last 24 hours. Formula milk was the largest contributor to child’s energy intake amongst the control children. Conclusions: The low dietary diversity warn potential problems for the health of Indonesian children. A large government strategy on complementary feeding practices including controlling the marketing activities of formula milk need to be enhanced.