Microbiological Quality and Safety of Mandrakpa, a Traditional Fermented Cereal Beverage from Bunia, Ituri Province, Democratic Republic of the Congo

Abstract

Purpose: This study evaluated the microbiological quality and safety of Mandrakpa, a traditional spontaneously fermented cereal beverage widely consumed in Bunia, Democratic Republic of the Congo, for which microbiological safety data were previously unavailable.

Methodology: Thirty Mandrakpa samples were collected from six production and sales areas in Bunia. Samples were analyzed for pH, total aerobic mesophilic bacteria (TAMB), lactic acid bacteria (LAB), yeasts, moulds, total coliforms, faecal coliforms, Staphylococcus aureus, and Salmonella spp. Microbial counts were expressed as log₁₀ CFU/mL. Differences among sampling areas were assessed using one-way analysis of variance (ANOVA) followed by Tukey’s HSD test at p < 0.05.

Findings: The pH of Mandrakpa ranged from 4.62 to 5.02, with an overall mean of 4.84 ± 0.17, indicating active fermentation and a consistently acidic environment. Total aerobic mesophilic bacteria ranged from 6.06 ± 0.04 to 7.31 ± 0.05 log₁₀ CFU/mL, while LAB populations ranged from 5.33 ± 0.04 to 6.74 ± 0.06 log₁₀ CFU/mL. Yeast counts varied from 4.94 ± 0.07 to 6.72 ± 0.68 log₁₀ CFU/mL, and mould counts ranged from 5.00 ± 0.00 to 5.48 ± 0.19 log₁₀ CFU/mL. Total coliforms and faecal coliforms were detected in all samples, with counts ranging from 3.26 ± 0.21 to 3.47 ± 0.02 log₁₀ CFU/mL and from 2.93 ± 0.06 to 3.32 ± 0.04 log₁₀ CFU/mL, respectively, exceeding internationally accepted microbiological limits for ready-to-eat foods. Staphylococcus aureus was detected in all samples at levels ranging from 2.49 ± 0.17 to 4.19 ± 0.12 log₁₀ CFU/mL, with most samples exceeding the alert threshold associated with potential enterotoxin production. Salmonella spp. was not detected in any of the 30 samples analyzed after selective enrichment and biochemical confirmation. One-way ANOVA revealed significant differences among sampling areas for TAMB, LAB and S. aureus (p < 0.05).

Unique Contribution to Theory, Practice and Policy: The study demonstrates that LAB-mediated fermentation and the resulting acidic pH contribute to the inhibition of enteric pathogens such as Salmonella spp. and support the microbiological stability of Mandrakpa. However, fermentation alone does not prevent contamination by hygiene-related microorganisms. The widespread presence of faecal coliforms, elevated mould counts, and high levels of Staphylococcus aureus highlight critical deficiencies in water quality, equipment sanitation, and handling practices. Although Mandrakpa shows considerable potential as a fermented cereal beverage, it does not currently meet international microbiological safety standards. The implementation of good hygienic practices, vendor training, and the development of controlled fermentation systems using selected starter cultures are recommended to improve product safety while preserving its traditional characteristics.