62 research outputs found
Optimization of Unit Operations for Microencapsulating Ferrous Fumarate During Scale-Up of Double Fortification of Salt with Iron and Iodine
Objectives: This study evaluates factors responsible for the floating of iron premix in double fortified salt (DFS), which initially affected the large-scale implementation of the salt fortification program in India, and provides solutions to the scale-up of the technology.
Materials and Methods: To mitigate this time-sensitive scale-up challenge. First, the iron premix samples were obtained from the industrial scale-up pilot studies in India, evaluated for the impact of the amount of coating material (5 per cent, 7.5 per cent, and 10 per cent (in weight)), type of formulation (soy stearin, SEPIFILM and hydroxypropyl methylcellulose), amount of titanium dioxide (25-35 per cent (in weight)) used for color masking; Second, we studied the effect of change in the composition of the coating, from 10 per cent (in weight) soy stearin to a double coat with 5 per cent (in weight) hydroxypropyl methylcellulose and 5 per cent soy stearin or 10 per cent soy stearin and 1 per cent (in weight) lecithin mixture, on particle density, floating or sinking property of the iron premix, and on the stability of iodine in the DFS.
Results: It was observed that the hydrophobic nature and the amount of soy stearin used for coating caused the floating issue. The double coating with 5 per cent hydroxypropyl methylcellulose and 5 per cent soy stearin was preferred because lecithin in soy stearin enhanced the moisture-aided adverse interaction between iron and iodine. Shelf-life storage studies proved over 80 per cent iodine retention after 12 months of storage in the DFS formulated with iron premix double-coated with hydroxypropyl methylcellulose and soy stearin.
Conclusion: This proffered solution enabled the full implementation of the double fortification program in India
Iron-Polyphenol Interaction Reduces Iron Bioavailability in Fortified Tea: Competing Complexation to Ensure Iron Bioavailability
Tea seems to be like a logical substrate for iron fortification; however, its fortification with iron presents technical challenges as tea polyphenols form a blue complex with iron that makes both of them unavailable for absorption. The objective of this work was to develop an effective technology, to prevent the interaction of iron and polyphenols by using EDTA as a competing complexing agent. Fortified tea was prepared from premix, prepared by spraying iron and sodium EDTA into tea leaves. Iron concentration in tea was adjusted to 5 mg/cup. Iron content was measured by AAS and the iron-polyphenol complex by spectrophotometry at 560 nm. Sensory evaluation was carried out in order to determine if fortification affects the properties of tea. A molar ratio of 1 : 2 Fe : EDTA was able to avoid complex formation and provide 4 mg of iron per cup of brewed tea. The fortified tea had a similar colour and flavour as ordinary tea, without the development of off-flavours. However, fortified tea with a ratio lower than 1 : 2 had a darker colour and off-flavours. By the addition of EDTA in a molar ratio ≥1 : 2, it is possible to produce an iron fortified tea without the formation of off-flavours
Characterizing the pH-dependent release kinetics of food-grade spray drying encapsulated iron microcapsules
“This work was carried out with the aid of a grant from Canada’s International Development Research Centre (IDRC), and with financial support from the Government of Canada, provided through Global Affairs Canada (GAC).”This detailed study models the release behavior of reverse enteric spray-dried microcapsules under different pH conditions, to better understand the release of iron fortificants. Spray drying is one of the mechanisms used for microencapsulating water-soluble iron salts with desired coating materials. Food fortification is an inexpensive and effective method to increase the intake of iron without compromising dietary customs. Of three models, the Eudragit coating, due to higher solid content, can handle a higher amount of iron payload. The new methodology developed for studying iron release of microencapsulated microparticles could be used in future applications in food fortification research
A Unified Analysis of Balancing Domain Decomposition by Constraints for Discontinuous Galerkin Discretizations
The BDDC algorithm is extended to a large class of discontinuous Galerkin (DG) discretizations of second order elliptic problems. An estimate of C(1 + log(H/h))2 is obtained for the condition number of the preconditioned system where C is a constant independent of h or H or large jumps in the coefficient of the problem. Numerical simulations are presented which confirm the theoretical
results. A key component for the development and analysis of the BDDC algorithm is a novel perspective presenting the DG discretization as the sum of element-wise “local” bilinear forms. The element-wise perspective allows for a simple unified analysis of a variety of DG methods and leads naturally to the appropriate choice for the subdomain-wise local bilinear forms. Additionally, this new perspective enables a connection to be drawn between the DG discretization and a related continuous finite element discretization to simplify the analysis of the BDDC algorithm.Boeing CompanyMassachusetts Institute of Technology (Zakhartchenko Fellowship
Improved salt iodation methods for small-scale salt producers in low-resource settings in Tanzania
Background:
Universal salt iodation will prevent iodine deficiency disorders (IDD). Globally, salt-iodation technologies mostly target large and medium-scale salt-producers. Since most producers in low-income countries are small-scale, we examined and improved the performance of hand and knapsack-sprayers used locally in Tanzania.
Methods:
We studied three salt facilities on the Bagamoyo coast, investigating procedures for preparing potassium-iodate solution, salt spraying and mixing. Different concentrations of solution were prepared and tested using different iodation methods, with the aim of attaining correct and homogeneous iodine levels under real-life conditions. Levels achieved by manual mixing were compared to those achieved by machine mixing.
Results:
The overall median iodation level in samples of salt iodated using previously existing methods was 10.6 ppm (range 1.1 – 110.0 ppm), with much higher levels in the top than the bottom layers of the salt bags, p < 0.0001. Experimentation using knapsack-sprayers and manual mixing led to the reliable achievement of levels (60.9 ppm ± 7.4) that fell within the recommended range of 40 – 80 ppm. The improved methods yielded homogenous iodine concentrations in all layers of salt-bags (p = 0.58) with 96% of the samples (n = 45) falling within 40 – 80 ppm compared to only 9% (n = 45) before the experiment and training (p < 0.0001). For knapsack-spraying, a machine mixer improved the iodine levels and homogeneity slightly compared to manual mixing (p = 0.05).
Conclusion:
Supervised, standardized salt iodation procedures adapted to local circumstances can yield homogeneous iodine levels within the required range, overcoming a major obstacle to universal salt iodation
Household and market survey on availability of adequately iodized salt in the Volta region, Ghana
This is an Accepted Manuscript of an article published by Taylor & Francis in International Journal of Health Promotion and Education on 27/10/2016, available online: http://www.tandfonline.com/doi/full/10.1080/14635240.2016.1250658Consumption of adequately iodized salt (AIS) ≥15ppm is one of the criteria for measuring progress towards universal salt iodization (USI) and sustainable elimination of iodine deficiency disorders. After series of health promotion activities, this survey was conducted to evaluate the extent to which USI was achieved. Cross-sectional survey was conducted in 1,961 households and 350 markets to estimate the iodine levels of salt consumed or sold. Three degrees of iodization were estimated from fine, coarse and granular texture salt using MBI rapid field test kits. Differences in iodization levels were determined using Bonferroni test in STATA. Determinants for household utilization of AIS were identified using regression analysis and reported as odds ratio (OR). Availability of AIS in households (24.5%) and markets (30.9%) was far below the 90% recommendation. No differences where observed in urban (26.8%) and rural (24.1%) households. Households that used fine-texture salt (OR: 40.13; CI: 30.1-53.4) or stored salt in original packs (OR: 8.02; CI: 6.01-10.70) were more likely to consume AIS. Across districts, highest household availability of AIS was 51.7% while the least was 7.5%. The district with the highest market availability of AIS was 85.7% while the least was 8.3%. Almost 32% of the traders were aware that selling non-iodized salt was unauthorized but out of this, only 12% sold AIS. Public education should emphasis appropriate handling and storage of salt throughout the supply chain. To ensure adequate salt fortification with iodine, improved surveillance of factories and mining sites is recommended
Сберегательное поведение в контексте исследования белорусской деловой культуры
Материалы X Международной научной конференции 25–26 мая 2017 г
Continuous Ethanol Fermentation in Immersed, Cross-Flow Microfiltration Membrane Bioreactor with Cell Retention
The key objective of this study was to devise a continuous ZeeWeed® membrane-based, immersed, microfiltration (MF) laboratory scale fermentation system for ethanol production with cell retention to achieve effective ethanol productivity, flux rates and sugar utilization. The new bioreactor was compared to the fermentation kinetics’ of the ultrafiltration unit.A synthetic glucose based medium was fermented by fresh, baker’s yeast to produce ethanol. The cells were not recycled; the medium was continuously withdrawn by filtration through an internal, immersed hollow-fiber cartridge. In this way, the inside of the membrane was exposed to the ethanolic solution, while broth with viable yeast cells remained outside the membrane. This design, with a cell retention system, provided much less membrane fouling (loss of about 76% of the original water flux after 96 hours of filtration) than while using the ultrafiltration (UF) external hollow-fiber membrane with cell recycling (loss of 97% of the original water flux after 2-3 hours of operation). Both modules converted at least 95% of glucose with biomass concentration of 30 g/L, and the final ethanol concentration of 62 g/L. However, the UF membrane became plugged after only 2 hrs of operation. The ZeeWeed® membrane operated successfully for 96 hrs with a final flux of 4 L/h m2 with ethanol concentration of 62.4 g/l, biomass yield 0.34 g/g and cell viability of 95.3%. This concept could be successfully used for biofuel production. A very strong positive correlation was observed between the biomass and EtOH concentration (R=0.98; at
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