Cereal-based fermented foods as microbiota-directed products for improved child nutrition and health in sub-Saharan Africa

Several strategies, programs and policies have long been developed and implemented to alleviate child malnutrition in sub-Saharan African countries. However, stunting and wasting still persist at an alarming rate, suggesting that alternative strategies are needed to induce faster progress toward the 2030 SDGs targets of reducing malnutrition. Gut microbiota-directed intervention is now being recognized as an unconventional powerful approach to mitigate malnutrition and improve overall child health. In an African setting, manufactured probiotic and synbiotic foods or supplements may not be successful owing to the non-affordability and high attachment of African populations to their food tradition. This review analyses the potential of indigenous fermented cereal-based products including porridges, doughs, beverages, bread- and yoghurt-like products, to be used as microbiota-directed foods for over 6 months children. The discussion includes relevant strategies to effectively enhance the beneficial effects of these products on gut microbiota composition for improved child health and nutrition in sub-Saharan Africa. Characterization of probiotic features and general safety of food processing in sub-Saharan Africa as well as randomized clinical studies are still lacking to fully ascertain the health effects and suitability of these fermented foods in preventing and treating child malnutrition and 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.

Nutritional and Phytochemical Composition of Mahewu (a Southern African Fermented Food Product) Derived from White and Yellow Maize (Zea mays) with Different Inocula

Mahweu is an important indigenous beverage for many low-income and undernourished consumers in southern Africa. As a result, the nutritional and phytochemical profile of mahewu samples (obtained using optimized fermentation and boiling conditions from a previous study) as well as their related raw materials (white and yellow maize) were investigated. At these conditions, white and yellow maize mahewu (WM and YM) were prepared utilizing various inocula including sorghum malt, wheat, millet malt, or maize malt, and the pH, titratable acidity (TTA), total soluble solid (TSS), and proximate analysis were determined. The mineral content, amino acid composition, and phenolic compound profile were also investigated using inductive coupled plasma optical emission spectrometry (ICP-OES), high-performance liquid chromatography (HPLC), and ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS), respectively. Fermentation was observed to have influenced the proximate composition of obtained mahewu samples compared to the raw flour with significant (p ≤ 0.05) improvement in protein from 8.59 to 9.7% (YM) and 8.78 to 9% (WM) as well as carbohydrate from 72.27 to 74.47% (YM) and 71.15 to 72.65% (WM). Sodium, magnesium, phosphorous, potassium, calcium, manganese, iron, copper, and zinc were the minerals detected in the mahewu samples, while potassium was the most abundant mineral, having values ranging from 3051.61 to 3283.38 mg/kg (YM) and 2882.11 to 3129.97 mg/kg (WM). Heavy metals detected in this study were all below the recommended tolerable levels by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Arginine and leucine with values ranging from 0.47 to 0.52 g/100 g (YM) and 0.48 to 0.53 g/100 g (WM) as well as 0.91 to 1.04 g/100 g (YM) and 0.95 to 1.01 g/100 g (WM), respectively, were the most abundant essential amino acids, whereas for non-essential amino acids, glutamic acid, aspartic acid, alanine, and proline were observed to be abundant. Based on the different inocula, the derived mahewu samples prepared using either white or yellow maize have varying nutritional and health beneficial components and the choice of inocula might still be determined by consumer preference.

African fermented foods: overview, emerging benefits, and novel approaches to microbiome profiling

Traditional fermented foods are of major importance with respect to the socio-economic growth, food security, nutrition, and health of African consumers. In several African countries, traditional fermentation processes provide a means of food preservation, improving the shelf life and adding to the nutrients in the food products. As with any fermented foods, the associated food microbiota is of great importance and interest. Recent studies on the microbiome of African fermented foods using high-throughput DNA sequencing techniques have revealed the presence of diverse microbial populations of fundamental, technological, and commercial interest that could be harnessed to further improve health, food safety, and quality. This review provides an overview of African fermented foods, their microbiota, and the health-promoting potential of these foods and microbes.

Tejuino, a Traditional Fermented Beverage: Composition, Safety Quality, and Microbial Identification

This study aims to analyze the chemical and microbial composition and characterize volatile compounds from the artisanal and commercial Tejuino beverage. For this, eight samples are analyzed (four artisanal and four commercial). The chemical and microbiological quality is determined by standard methods, and volatile compounds are determined by solid-phase microextraction. Overall, the physicochemical composition and microbiological quality are higher for artisanal Tejuino (p < 0.05). The pH values were 3.20 and 3.62, and 0.76 and 0.46 meq of lactic acid for artisanal and commercial Tejuino, respectively. With volatile compounds analyzed, esters, benzenes, and aldehydes were predominant; meanwhile, ethanol was a volatile compound with the highest concentration for all samples. Saccharomyces cerevisiae and Limosilactobacillus fermentum were identified in artisanal Tejuino; yeasts of the Pichia genera and Lactiplantibacillus plantarum, for commercial Tejuino, and Enterococcus genus were identified in both samples. The characterization of both types of Tejuino allows us to update the information available on this important Mexican beverage. In addition, the isolation of lactic acid bacteria, as representative bacteria of both drinks, offers an area of opportunity to know the potential functionality of these bacteria in traditional fermented products.