Improved energy intakes using amylase-digested weaning foods in Tanzanian children with acute diarrhea

Microbial Diversity in African Foods and Beverages: A Systematic Assessment

This article provides a comprehensive and in-depth examination of the microbial diversity inherent in African food and beverages, with a particular emphasis on fermented products. It identifies and characterizes the dominant microorganisms, including both prokaryotes and yeasts, prevalent in these foods, and furthermore, critically analyzes the health benefits of these microbial strains, especially their probiotic properties, which could potentially improve digestion and contribute to human health. Notably, it underscores the vital role these microorganisms play in bolstering food security across Africa by enhancing and preserving food quality and safety. It also delves into the potential applications of microbial products, such as metabolites, in the food industry, suggesting their possible use in food processing and preservation. Conclusively, with a summarization of the key findings, emphasizing the importance of gaining a deep understanding of microbial diversity in African beverages and foods. Such knowledge is crucial not only in promoting food security but also in advancing public health.

Dietary management of childhood diarrhea in low- and middle-income countries: a systematic review

Background

Current WHO guidelines on the management and treatment of diarrhea in children strongly recommend continued feeding alongside the administration of oral rehydration solution and zinc therapy, but there remains some debate regarding the optimal diet or dietary ingredients for feeding children with diarrhea.

Methods

We conducted a systematic search for all published randomized controlled trials evaluating food-based interventions among children under five years old with diarrhea in low- and middle-income countries. We classified 29 eligible studies into one or more comparisons: reduced versus regular lactose liquid feeds, lactose-free versus lactose-containing liquid feeds, lactose-free liquid feeds versus lactose-containing mixed diets, and commercial/specialized ingredients versus home-available ingredients. We used all available outcome data to conduct random-effects meta-analyses to estimate the average effect of each intervention on diarrhea duration, stool output, weight gain and treatment failure risk for studies on acute and persistent diarrhea separately.

Results

Evidence of low-to-moderate quality suggests that among children with acute diarrhea, diluting or fermenting lactose-containing liquid feeds does not affect any outcome when compared with an ordinary lactose-containing liquid feeds. In contrast, moderate quality evidence suggests that lactose-free liquid feeds reduce duration and the risk of treatment failure compared to lactose-containing liquid feeds in acute diarrhea. Only limited evidence of low quality was available to assess either of these two approaches in persistent diarrhea, or to assess lactose-free liquid feeds compared to lactose-containing mixed diets in either acute or persistent diarrhea. For commercially prepared or specialized ingredients compared to home-available ingredients, we found low-to-moderate quality evidence of no effect on any outcome in either acute or persistent diarrhea, though when we restricted these analyses to studies where both intervention and control diets were lactose-free, weight gain in children with acute diarrhea was shown to be greater among those fed with a home-available diet.

Conclusions

Among children in low- and middle-income countries, where the dual burden of diarrhea and malnutrition is greatest and where access to proprietary formulas and specialized ingredients is limited, the use of locally available age-appropriate foods should be promoted for the majority of acute diarrhea cases. Lactose intolerance is an important complication in some cases, but even among those children for whom lactose avoidance may be necessary, nutritionally complete diets comprised of locally available ingredients can be used at least as effectively as commercial preparations or specialized ingredients. These same conclusions may also apply to the dietary management of children with persistent diarrhea, but the evidence remains limited.

Food Viscosity Influences Caloric Intake Compensation and Body Weight in Rats

OBJECTIVE

To determine the effects of food viscosity on the ability of rats to compensate for calories in a dietary supplement.

RESEARCH METHODS AND PROCEDURES

In a series of four experiments, rats consumed dietary supplements equated for caloric and nutritive content but differing in viscosity. Experiments 1 to 3 examined the ability of the rats to compensate for the calories consumed in low- compared with high-viscosity premeals by reducing intake of a subsequent test meal. Caloric compensation was assessed with a wide range of premeal viscosity levels and with two different non-nutritive thickening agents. Experiment 4 assessed the effects of consuming daily a low-viscosity compared with an equicaloric high-viscosity dietary supplement on longer term body weight gain.

RESULTS

Consuming a lower viscosity premeal was followed by significantly more caloric intake (i.e., less caloric compensation) compared with consuming premeals with higher viscosity levels. This effect was not specific to one thickening agent. Furthermore, rats given a low-viscosity supplement daily gained significantly more weight over a 10-week period compared with rats given a high-viscosity supplement.

DISCUSSION

The results of these experiments suggest that food viscosity may be an important determinant of short-term caloric intake and longer term body weight gain.

Traditional non-alcoholic beverage, Togwa, in East Africa, produced from maize flour and germinated finger millet

The traditional non-alcoholic beverage in East Africa, togwa, produced from the flour of maize and germinated finger millet (finger millet malt), was investigated. The preparation techniques of togwa observed in the rural villages of East Africa are described, and the temperature and pH profile of togwa during its manufacture are also shown. Maize and finger millet malt should be the source of starch and amylase, respectively. Maize flour slurry was heated once with stirring up to around 80 degrees C and cooled to about 50 degrees C, and then finger millet malt flour was added to the warm porridge paste and kept at about 50 degrees C for 20 min. The consistency of the paste was suddenly reduced by addition of finger millet malt flour and the gel paste changed to viscous liquid, which was kept in a container and incubated at ambient temperature for 15 h. After incubation it became sweet and was ready to drink without removal of any insoluble materials. Changes in the concentration of glucose and lactic acid of togwa during its maturation period were measured using portable devices until 70 h incubation at the rural village of Tanzania in a dry season. Glucose level increased with incubation and reached the threshold value of sweetness; 24 h incubation later, the lactate level increased and pH decreased. The preparation techniques of a traditional alcoholic beverage, pombe, were also investigated in the same rural locality, and the differences and characteristics of both traditional beverages are discussed.

Fortified complementary foods with or without alpha-amylase treatment increase hemoglobin but do not reduce breast milk intake of 9-mo-old Zambian infants

BACKGROUND

Malnutrition in late infancy in developing countries may result from poor-quality complementary foods that displace breast milk.

OBJECTIVE

The objective of the study was to assess the effects of fortified complementary blends of different energy densities on growth, hemoglobin concentrations, and breast milk intake of 9-mo-old Zambian infants.

DESIGN

Infants were randomly assigned at 6 mo of age to receive for 3 mo a fortified blend of maize, beans, bambaranuts, and groundnuts [Chilenje Baby Mix (CBM); energy density: 68 kcal/100 g; n = 37] or a similar blend with alpha-amylase (CBMA; energy density: 106 kcal/100 g; n = 44). Cross-sectional data were obtained at 9 mo for a control group of infants (n = 69) not given the diets. Breast milk intake was measured by using the dose-to-the-mother deuterium dilution technique.

RESULTS

No differences in weight or length z scores, all of which were within normal ranges, were seen between groups at 9 mo. Percentage fat mass was significantly (P = 0.01) greater in the infants in both the CBM (23.2 +/- 2.7%) and CBMA (23.4 +/- 2.5%) groups than in the control group (21.6 +/- 2.6%). Hemoglobin concentrations were significantly (P = 0.03) greater in both intervention groups (CBM group: 104 +/- 12 g/L: CBMA group: 103 +/- 12 g/L) than in the control group (98 +/- 14 g/L). Breast milk intake was not significantly (P = 0.87) different between groups (CBM group: 614 +/- 271 g/d; CBMA group: 635 +/- 193 g/d; control group: 653 +/- 221 g/d).

CONCLUSIONS

The study foods improved hemoglobin concentrations without reducing breast milk intake and may be used to improve the nutritional status of infants in developing countries.

Influence of the technological know-how of producers on the biochemical characteristics of red sorghum malt from small scale production units in Ouagadougou (Burkina Faso)

The process of red sorghum malt production was monitored three times in five production units (PU) selected upon their ability to produce malt flours having a high capacity to fluidify high-energy-density gruels. Raw, germinated and degermed seeds were analysed for macronutrient, soluble sugars, phytate and cyanide contents and alpha-amylase activity. Know-how differences between producers lay mainly in the duration and type of equipment used for steeping and germination. Moreover, three PUs applied a maturation step before sun-drying and one PU added ashes to steeped seeds before germination. No significant difference was detected in the proximate composition of malts from the five PUs. For all PUs, traditional malting increased the protein content and decreased the lipid and ash contents, while the fibre content was not affected. Significant increases in sugar contents and in alpha-amylase activity were observed but in variable proportions from one PU to another. The phytate content decreased significantly in all PUs. The cyanide content increased in all PUs but more drastically or less drastically according to the PU. Finally, degerming lowered the cyanide content to an acceptable level for human consumption. The between-PU variability may be due either to the nature and origin of the raw seeds or to technological know-how differences between producers. Further investigations are needed to optimize and standardize the malting process with a view to maximizing alpha-amylase and phytase activities and minimizing the variability of their biochemical characteristics.

Spontaneously fermented millet product as a natural probiotic treatment for diarrhoea in young children: an intervention study in Northern Ghana

Indigenous lactic acid fermented foods may have potential as probiotic treatment for diarrhoea, due to high levels of lactic acid bacteria. In this study the effect of a millet drink, spontaneously fermented by lactic acid bacteria, as a therapeutic agent among Ghanaian children with diarrhoea, was assessed. Children below 5 years of age coming to Northern Ghana health clinics for treatment of diarrhoea were randomised to two groups. Children of both groups received treatment for diarrhoea given at the local clinic. The intervention group in addition received up to 300 ml fermented millet drink (KSW) daily for 5 days after enrolment. The clinical outcome of diarrhoea and reported well-being were registered every day for the 5-day intervention and again 14 days after diagnosis. Among 184 children (mean age 17.4, standard deviation 11.3 months) included, no effects of the intervention were found with respect to stool frequency, stool consistency and duration of diarrhoea. However, KSW was associated with greater reported well-being 14 days after the start of the intervention (P=0.02). The fact that no effect of KSW on diarrhoea was observed could be because many children had a mild form of diarrhoea, and many were treated with antibiotics. Either this could have affected the lactic acid bacteria, or the lactic acid bacteria in KSW had no probiotic effects. It is speculated that the effect after two weeks could be due to a preventing effect of KSW on antibiotic-associated diarrhoea which could help reducing persistent diarrhoea.

Use of starter cultures of lactic acid bacteria and yeasts in the preparation of togwa, a Tanzanian fermented food

Starter cultures of lactic acid bacteria (Lactobacillus brevis, Lactobacillus cellobiosus, Lactobacillus fermentum, Lactobacillus plantarum and Pediococcus pentosaceus) and yeasts (Candida pelliculosa, Candida tropicalis, Issatchenkia orientalis and Saccharomyes cerevisiae) isolated from native togwa were tested singly or in combination for their ability to ferment maize-sorghum gruel to produce togwa. All species of bacteria showed an ability to ferment the gruel as judged by lowering the pH from 5.87 to 3.24-3.49 and increasing the titratable acidity from 0.08% to 0.30-0.44% (w/w, lactic acid) in 24 h. Yeasts used singly showed little activity within 12 h, but lowered the pH to 3.57-4.81 and increased the acidity to 0.11-0.21% in 24 h. Yeasts in co-culture with lactic acid bacteria (LAB) had a modest effect on the final acidity (P<0.05). The number of lactic acid bacteria and yeasts increased while the Enterobacteriaceae decreased with fermentation time. The pH was lowered and lactic acid produced significantly (P<0.05) fastest in natural togwa fermentation and in samples fermented by L. plantarum or L. plantarum in co-culture with I. orientalis. The content of fermentable sugars was reduced during fermentation. Most volatile flavour compounds were produced in samples from fermentation by P. pentosaceus and I. orientalis in co-culture with either L. plantarum or L. brevis.

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.

Household-level technologies to improve the availability and preparation of adequate and safe complementary foods

Plant-based complementary foods are the main source of nutrients for many young children in developing countries. They may, however, present problems in providing nutritionally adequate and safe diets for older infants and young children. The high starch content leads to low-nutrient diets that are bulky and dense, with high levels of antinutritive factors such as phytates, tannins, lectins, and enzyme inhibitors. Phytates impair mineral bioavailability, lectins interfere with intestinal structure, and enzyme inhibitors inhibit digestive enzymes. In addition, there is often microbial contamination, which leads to diarrhea, growth-faltering, and impaired development, and the presence of chemical contaminants may lead to neurological disease and goiter. The fact that some fruits containing carotenoids are only available seasonally contributes to the vulnerability of children receiving predominantly plant-based diets. Traditional household food technologies have been used for centuries to improve the quality and safety of complementary foods. These include dehulling, peeling, soaking, germination, fermentation, and drying. While modern communities tend to reject these technologies in favor of more convenient fast-food preparations, there is now a resurgence of interest in older technologies as a possible means of improving the quality and safety of complementary foods when the basic diet cannot be changed for economic reasons. This paper describes the biology, safety, practicability, and acceptability of these traditional processes at the household or community level, as well as the gaps in research, so that more effective policies and programs can be implemented to improve the quality and safety of complementary foods.

Nutritional management of acute diarrhea

Despite recommendations from several bodies such as the World Health Organization and others that feeding should be continued during diarrhea, the practice of withholding food during the early stages of diarrhea is still widespread. This contributes to a deterioration in patients' nutritional state. The principal controversy in the nutritional therapy of acute gastroenteritis centers on the relative risks of cows'-milk feeds. The two things that need to be considered in determining the optimum approach to feeding the child with acute diarrhea are the optimum timing for feeding children in relation to the onset of and recovery from symptoms and, secondly, the effects of specific food ingredients in the diet. Recent studies have demonstrated that the vast majority of young children with acute diarrhea can be successfully managed with continued feeding of undiluted non-human milk. Routine dilution of milk and routine use of lactose-free formula are not necessary, especially when oral rehydration therapy and early feeding (in addition to milk) form the basic approach to the clinical management of diarrhea in children. Confounding factors are the severity of the diarrhea, coexistent malnutrition, and young age (< 1 y); such infants are much more likely to have complications from early feeding with undiluted milk and some would advocate use of specifically designed lactose-free formula in such children. Children who are fed exclusively with human milk and those who receive solid foods with or without human milk may safely continue to receive their usual diets during diarrhea. Those who are fed exclusively with non-human milk--especially when very young and with severe diarrhea or malnutrition--should be closely observed if they continue to consume milk or they should receive a special formulation (e.g., a cereal-milk mixture or fermented milk product). The use of nutrient-dense mixtures of common foods may be advisable to promote compensatory growth in those who lose weight during illness or because of anorexia or malabsorption.

Maternal Preferences for Consistency of Complementary Foods in Guatemala

Increasing the nutrient density of complementary food mixtures is a common strategy for improving child nutrition in developing countries. Such modification, however, typically increases the viscosity of the mixtures, which may not appeal to caretakers or children. To assess maternal preference for complementary food consistency, 46 rural Guatemalan mothers, each of whom had a child between 6 and 14 months of age, were interviewed by trained data collectors and participated in focus group discussions. Strong opinions regarding consistencies of complementary foods were identified, which varied according to the child's age and health status. Mothers preferred thinner complementary foods for children less than one year old and thicker foods for children more than one year old. When the child had a cough or fever, most mothers preferred thin, liquid complementary foods. When the child had diarrhoea, about half of the mothers believed thinner complementary foods would replace the water the child lost with diarrhoea, whereas other mothers believed that thicker complementary foods would harden the stool or stop diarrhoea. This information will help guide efforts to develop improved complementary foods, particularly those for use during illness in underprivileged populations of developing countries.

Dietary management of acute diarrhoea in children: effect of fermented and amylase-digested weaning foods on intestinal permeability

BACKGROUND

There is a strong relationship between diarrhoea, malnutrition, and intestinal integrity. To investigate the effect of different dietary-treatment on intestinal permeability during acute diarrhoea, 87 Tanzanian children aged 6-25 months were recruited to this study when admitted to hospital.

METHODS

Children with acute diarrhoea were rehydrated and then randomly assigned to one of three dietary treatment groups: a conventional low-energy density porridge, a high-energy density amylase digested porridge (AMD), or a high-energy density amylase digested and then fermented porridge (FAD). Lactulose/mannitol permeability tests were performed on admission, at 3 days, and at follow-up 2 and 4 weeks after discharge. The lactulose/mannitol (L/M) ratios were compared between dietary treatment groups and to a group of age-matched, healthy control subjects.

RESULTS

Children with diarrhoea had higher L/M ratios (geometric mean 0.85, 95% CI 0.68-1.05) compared with control subjects (0.14, 0.12-0.17) on admission. There was a significant difference in the change in L/M ratio between admission and 3 days between dietary treatment groups in favour of the FAD group (p < 0.05).

CONCLUSIONS

Dietary treatment and intestinal damage at admission explain 13.5% of the variation in L/M ratio, but when age at admission and age at weaning are included as covariants, 21.9% is explained. FAD porridge seems to be more effective in the treatment of intestinal permeability than AMD or conventional porridge. Urinary lactose concentrations in spot urine samples taken prior to the permeability test were also measured. There was a significant correlation with the L/M ratio (correlation coefficient = 0.62, p < 0.001).

Comparison of milk and maize based diets in kwashiorkor

The dual sugar test of intestinal permeability is a reliable non-invasive way of assessing the response of the small intestinal mucosa to nutritional rehabilitation.

AIM

To compare a local mix of maize-soya-egg to the standard milk diet in the treatment of kwashiorkor.

DESIGN

The diets were alternated three monthly in the sequence milk-maize-milk. There were a total of 533 kwashiorkor admissions of at least five days during the study who received either milk or maize. Intestinal permeability was assessed at weekly intervals by the lactulose-rhamnose test in 100 kwashiorkor cases, including 55 on milk and 45 on the maize diet.

RESULTS

Permeability ratios (95% confidence interval) on the milk diet improved by a mean of 6.4 (1.7 to 11.1) compared with -6.8 (-16.8 to 5.0) in the maize group. The improved permeability on milk occurred despite more diarrhoea, which constituted 34.8% of hospital days (29.8 to 39.8) compared with 24.3% (17.8 to 30.8) in the maize group. Case fatality rates for all 533 kwashiorkor admissions were 13.6% v 20.9%, respectively, giving a relative risk of death in the maize group of 1.54 (1.04 to 2.28). The maize group also had more clinical sepsis (60% v 31%) and less weight gain (2.9 v 4.4 g/kg/day) than the milk group.

IMPLICATIONS

Milk is superior to a local maize based diet in the treatment of kwashiorkor in terms of mortality, weight gain, clinical sepsis, and improvement in intestinal permeability.