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Anion-exchange high-performance liquid chromatography with conductivity detection for the analysis of phytic acid in food.

A sensitive method for the accurate determination of phytic acid in food samples is described. The proposed procedure involves the anion-exchange liquid chromatography with conductivity detection. Initially, two methods of determination of phytic acid were compared: absorptiometry and high-performance ion chromatography (HPIC) with chemically suppressed conductivity detector. Unlike most conventional methods involving precipitation by FeCl3, the simpler and more reliable HPIC assay avoids the numerous assumptions inherent in the iron precipitation and the accuracy is independent of the phytate content. The protocol was also applied to a survey of phytic acid concentration in some cereal, oil and legume seeds.

Deterioration in the nutritional status of young children and their mothers in Brazzaville, Congo, following the 1994 devaluation of the CFA franc

The effects of the January 1994 devaluation of the African Financial Community (CFA) franc on the nutritional situation of the populations concerned has been little documented. We report in this article on two nutritional cross-sectional surveys that were conducted before and after this devaluation (1993 and 1996) in two districts of Brazzaville, Congo. The surveys involved a representative sample of 4206 households with a child aged 4-23 months. Complementary feeding practices and the anthropometric indices of the children and their mothers were compared, adjusting for changes in household socioeconomic characteristics. The results show a decline in the quality of the first complementary foods offered to the infants, i.e. less frequent use of special transitional foods and imported complementary flours (of higher nutritional quality), and preparation of less nutritious local gruels. Overall, the nutritional situation had deteriorated, with greater levels of stunting and wasting among children, mothers with lower body mass index, and infants with reduced birth weights. Increased food prices would appear to be the direct cause of the decreased quality in complementary feeding, but factors other than the devaluation have also had an impact on household welfare. The influence of these factors on nutritional-status is discussed.

Biochemical changes occurring during growth and storage of two yam species

The biochemical changes occurring during growth and storage of two yam cultivars (Dioscorea rotundata cv. Oshei and Dioscorea dumetorum cv. Jakri) were studied. Tubers were harvested at monthly intervals from the fourth to the tenth month after 50% emergence of the planted yam sets. For storage studies, Oshei and Jakri tubers were harvested 9.5 and 9 months post-emergence, respectively. These were stored under prevailing tropical ambient conditions (18-31 degrees C, 62-100% RH) for 1,2,3 and 4 months. All samples were analysed for dry matter, crude protein, carbohydrate, essential amino acids and mineral contents. The maximum dry matter was reached in both cultivars 9 months post-emergence, being 40.4 and 26.4%, respectively for Oshei and Jakri tubers. This was judged to be the optimum time for harvesting. Starch reached maximum values of 86.7 and 78.3 g/100g, respectively after 6 months. Ethanol-soluble sugars declined from 9.4 to 2.3 g/100g in Oshei but remained constant at over 6.0 g/100g in Jakri tubers during growth. Crude protein values increased slightly to a maximum of 5.4 and 8.0 g/100g, respectively for Oshei and Jakri tubers. During storage, weight losses reached 31% in Oshei tubers and 35% in Jakri after 110 days due to sprouting and dehydration. Starch decreased by approximately 3.5-4.5 g/100g while sugars and fibre values increased slightly in both cultivars.

Effects of energy density and sweetness of gruels on Burkinabe infant energy intakes in free living conditions

In free living conditions, 24 breastfed infants, aged 6 to 10 months, were given successively five experimental gruels to study the effect of energy density (ED) and sweetness (sweet taste) on energy intakes (EI). Four gruels (G0, G1, G9 and G20) were prepared with experimental flours which were composed of the same local ingredients and which contained different levels of sucrose. The fifth gruel (GC) was prepared with an industrial flour. G0 had an average ED of 45 kcal/100 g (189 kJ/100 g) and the other gruels an average ED of 110 kcal/100 g (461 kJ/100 g). Although the sugar contents of the flours were 1% for G1, 9% for G0 and G9 and 20% for G20, because of flour composition and gruel dry matter content, the gruel G1 had the same sweetness as G0, G20 the same sweetness as GC and G9 a sweetness between that of G1 and G20. The results show that the amounts of G0 consumed were significantly higher than those of high ED gruels (7.84 for G0 vs 6.12, 5.63, 4.46, 4.72 g/kg body weight/meal, respectively for G20, G9, G1 and GC, P < 0.05). However, EI from high ED gruels were significantly (P < 0.001) higher than those from G0 (6.65, 6.10, 4.86, 4.83 kcal/kg/meal, respectively for G20, G9, G1 and GC vs 3.46 for G0). Energy intakes from G9 and G20 gruels were not significantly different but were significantly higher than those from GC and G1 (P < 0.001). So, consumption of sweet gruels with high ED and composed of local ingredients increased, at least by 76%, the EI from gruels in comparison with those from low ED gruels, but the amounts consumed by the infants remained too low to cover more than 15% of their daily total energy needs.In free living conditions, 24 breastfed infants, aged 6 to 10 months, were given successively five experimental gruels to study the effect of energy density (ED) and sweetness (sweet taste) on energy intakes (EI). Four gruels (G0, G1, G9 and G20) were prepared with experimental flours which were composed of the same local ingredients and which contained different levels of sucrose. The fifth gruel (GC) was prepared with an industrial flour. G0 had an average ED of 45 kcal/100 g (189 kJ/100 g) and the other gruels an average ED of 110 kcal/100 g (461 kJ/100 g). Although the sugar contents of the flours were 1% for G1, 9% for G0 and G9 and 20% for G20, because of flour composition and gruel dry matter content, the gruel G1 had the same sweetness as G0, G20 the same sweetness as GC and G9 a sweetness between that of G1 and G20. The results show that the amounts of G0 consumed were significantly higher than those of high ED gruels (7.84 for G0 vs 6.12, 5.63, 4.46, 4.72 g/kg body weight/meal, respectively for G20, G9, G1 and GC, P < 0.05). However, EI from high ED gruels were significantly (P < 0.001) higher than those from G0 (6.65, 6.10, 4.86, 4.83 kcal/kg/meal, respectively for G20, G9, G1 and GC vs 3.46 for G0). Energy intakes from G9 and G20 gruels were not significantly different but were significantly higher than those from GC and G1 (P < 0.001). So, consumption of sweet gruels with high ED and composed of local ingredients increased, at least by 76%, the EI from gruels in comparison with those from low ED gruels, but the amounts consumed by the infants remained too low to cover more than 15% of their daily total energy needs.

Viscosity of gruels for infants : a comparison of measurement procedures

Numerous studies have been carried out to investigate energy density and consistency of gruels for infants in developing countries. However, starch-rich gruels have a complex rheological behavior and their consistency is difficult to characterize. Many published gruel viscosity data are available, but the lack of standardized viscosity measurement procedures makes comparisons and interpretations difficult. The influences of viscometer type and viscosity measurement conditions on gruels prepared with simple or multicomponent flours were assessed in this study. The results showed a drastic decrease in apparent viscosity when the shear rate increased. Other factors like shear time and gruel temperature also had a marked influence on apparent viscosity. For two types of gruel (maize or multicomponent flour) prepared at different concentrations, correspondences between a short qualitative description of the consistency and apparent viscosity values obtained with several viscometers in different measurement conditions are given. Finally, recommendations are put forward on techniques to obtain valid data on gruel consistency, adapted to each type of study (laboratory, field or large-scale surveys).

Consumption pattern, biochemical composition and nutritional value of fermented pearl millet gruels in Burkina Faso

Ben-kida and ben-saalga are popular pearl-millet-based fermented gruels in Burkina Faso. A survey of 318 households in Ouagadougou (Burkina Faso) showed that they are often used as complementary food for young children. Pearl millet and gruels, sampled in 48 production units, were analysed for proximate composition, factors reducing nutrient bioavailability (phytate, insoluble fibres and iron-binding phenolic compounds), α-galactosides, sugars, total lactic acid and d-lactic acid, zinc and iron contents. The effects of processing of pearl millet into fermented gruel are discussed. Both positive effects (e.g. a decrease in factors reducing nutrient bioavailability or α-galactosides) and undesirable effects (e.g. considerable lipid, protein, iron and zinc losses) were observed. Lactic acid was produced during processing and d(−)-lactate was detected in all samples. The gruels had very low energy density, even after addition of sugar, and low lipid, protein and mineral contents, well below recommendations for complementary foods.

Characterization of the consistency of gruels consumed by infants in developing countries: assessment of the Bostwick consistometer and comparison with viscosity measurements and sensory perception

Standardized techniques are still needed to characterize the consistency of gruels for infants in developing countries. The aim of this study was to evaluate the interest of the use of the Bostwick consistometer. Bostwick flow was measured on gruels prepared with different flours, at low or high energy density (i.e. without or with amylase). The range of Bostwick flow, from 0 to 240 mm/30 sec, adequately described a wide range of gruel consistencies from completely liquid to almost solid. However, the temperature of the gruel must be carefully controlled during measurements as Bostwick flow is highly temperature dependent, especially in the case of gruels with high energy density. The relationship between Bostwick flow and apparent viscosity proved to depend on the type of gruel: at an apparent viscosity of 1 Pa.sec, gruels prepared from maize, rice, millet or multicomponent flours had different Bostwick flow values of, respectively, 20, 35, 75 and 55 mm/30 sec. Sensory analysis was then performed with a panel of mothers of infants and young children in Ouagadougou (Burkina Faso). Gruels of similar apparent viscosity and different Bostwick flow distances or of inversely similar Bostwick flow distances and different apparent viscosities were prepared by adding carob seed flour, and differentiation and ranking tests were then carried out. Both types of test revealed that mothers differentiated similar gruels having different Bostwick flow distances more easily than gruels having different apparent viscosities. It can thus be concluded that Bostwick flow, which is an empirical multi-criteria parameter, conveys the sensory perception of gruel consistency better than apparent viscosity.

Does the consumption of amylase-containing gruels impact on the energy intake and growth of Congolese infants?

OBJECTIVE To assess the effect of the incorporation of amylase in maize-based flours prepared as gruels on the energy intake and growth of Congolese infants. DESIGN A randomised controlled trial. At 18 weeks of age, infants were randomised into either an intervention group, where they were provided with a maize/soya-based flour that contained amylase, or a control group, where they were provided with a similar flour that did not contain amylase. SETTING Urban borough of Poto-Poto in Brazzaville, The Congo. SUBJECTS Eighty infants (40 in each group) were randomised into intervention and control groups. Three infants in the intervention group and two controls subsequently dropped out. RESULTS At 24 weeks, the addition of amylase resulted in a significant increase in energy intake (in kJ kg-1 day-1) from gruels without affecting breast milk consumption. In contrast, total energy intake (in kJ kg-1 day-1) did not differ significantly between groups (P= 0.08). After adjustment for morbidity and previous growth, infants in the intervention group showed better growth in length during the trial (+0.22 cm month-1; P= 0.04), especially between 24 and 31 weeks of age (+0.51 cm month-1; P< 0.01). There were no differences in weight velocity between groups. CONCLUSIONS The findings of this study suggest that the consumption of amylase-treated gruels allows an increase in energy intake from these gruels without affecting breast milk consumption but has no impact on total daily energy intake. However, if started after 6 months, it could be effective in preventing faltering of infant linear growth.

Marketing Complementary Foods and Supplements in Burkina Faso, Madagascar, and Vietnam: Lessons Learned from the Nutridev Program

Background Sustainable approaches to improving infant and young child feeding are needed. The Nutridev program worked in Vietnam, Madagascar, and Burkina Faso to test different strategies to improve complementary feeding using fortified products sold to families. Objective To review the experiences of programs producing and marketing fortified complementary foods and to report on the feasibility of local production and marketing of fortified complementary foods to increase usage of high-quality foods among children of low-income families in a self-sustaining manner. Methods Project documents, surveys of mothers, and production and sales reports were reviewed. Results Nutridev experience in Vietnam, Madagascar, and Burkina Faso demonstrates that it is possible to produce affordable, high-quality complementary foods and supplements locally in developing countries. Strategies to make products readily available to the targeted population and to convince this population to consume them yielded mixed results, varying greatly based on the strategy utilized and the context in which it was implemented. Conclusions In several contexts, the optimal approach appears to be strengthening the existing food distribution network to sell complementary foods and supplements, with the implementation of a temporary promotion and nutrition education network in partnership with local authorities (e.g., health services)to increase awareness among families about the fortified complementary food product and optimal feeding practices. In urban areas, where the density of the population is high, design and implementation of specific networks very close to consumers seems to be a good way to combine economic sustainability and good consumption levels.

Home-processing of the dishes constituting the main sources of micronutrients in the diet of preschool children in rural Burkina Faso

The diet of 200 randomly selected 1-year-old to 5-year-old children was studied in a rural area of Burkina Faso. The mothers took part in a questionnaire survey and a 24-h dietary recall to index the type and the ingested quantities of the food consumed by the child the previous day. The average percentages of the Recommended Nutrient Intake met by the consumption of a dish component per meal did not exceed 25% for energy, iron, zinc and vitamin A. With respect to their initial composition and the quantities ingested, several dish components such as starchy-based products (millet-based-tô) or sauces (red sorrel leaves, dried okra) were good sources of micronutrients in the childrens diets. Several dish components were selected and their preparation observed in six households to obtain precise details of the recipe. Several ingredients (42) and unit operations (nine) were used to prepare the local foods. Cooking in water (boiling), which was the main unit operation, did not exceed 43 min and the temperature used was under 100°C. Several ingredients were subjected to two or three thermal treatments and the duration of cooking reached 56 min in groundnut sauce. The most at-risk unit operations likely to decrease the nutritional quality were cooking in water followed by draining or cooking for a long time.