Microbiological quality of local soymilk: a public health appraisal

Abstract

The ubiquity in the hawking of locally produced soymilk, packaged in different forms, was considered a public health concern. The attendant increase in the rate of soymilk consumption has encouraged low scale production of the milk under household condition with little or no regard to quality control measures. Accordingly, branded and unbranded soymilk samples were subjected to microbiological analyses to ascertain their hygienic standard of production. The soymilk samples were found to have pH in the range of pH 7.2 to 7.5. Screening for microbial contaminants revealed generally high bacterial and fungal counts of 2.9 x 10⁷ cells/ml. to 1.02 x 10⁸ cells/ml. and 3.5 x 10⁷ to 2.13 x 10⁸ cells/ml. respectively as well as high Most Probable Number (180⁺) of coliform bacilli per 100ml of each sample. Regular contamination with Escherichia coli, other faecal coliforms and Staphylococcus aureus was detected in all the samples. In addition, Pseudomonas aeruginosa, other Gram-negative bacilli and streptobacilli were detected in most of the nylon packed (unbranded) samples. The fungal isolates were mainly Aspergillus spp., Penicillium spp and Fusarium. The microbial population detected in terms of number and types reflected poor hygienic standard of production, constituting a public health hazard among the populace. There is a need to streamline soymilk
production for proper monitoring and quality assurance.

Keywords: Microbiological quality, local soymilk, public health.

La non-regularisation dans la vente a la sauvette du lait de soja produit localement et ensechete sous differentes formes est considere comme un probleme de sante publique. L’augmentation du taux de consommation du lait de soja a encourage la production a basse echelle de lait domestiquement et sans respect des mesures de controle de la qualite. Respectivement d’echantellons de marques deposes et non - inregistre’s de lait de soja etaient passees sous analyses microbiologigues pour determiner leur niveau hygiunique de production. Des echantillons de lait de soja s’averaient avoir un pH de 7.2 a 7.5. In selectionnant par contamination microbienne le taux de bacteries et de fungites s’averaient deve’s 2.9 x 10⁷ cellules/ml - 1.02 x 10⁸ cellules/ml et 3.5 x 10⁷ - 2.13 x 10⁸ cellules/ml respectivement, aussi le nombre eleve le plus problable (1.80⁺) de bacille coliforme par 100ml de chaque echanlellon. La contamination reguliere de Escherichia. coli (E-coli), di autres coliforme fecaux et de staphylocoques Aureus etait detecte dans tous les echantillons. De plus, despseudonome aeruginoso, d’autres bacilles de gramme negative et desstreptocoques etaient detectees dans la plupart des echantillons ensaches (non- enregistres). Les fungites isoles etaient principalement l’aspergille sp, penicillium sp et Fusaruum sp. la population microbienne detectee en nombre et types reflecte la pauvre standard d’Hygiene de production constituent un danger (obstacle) pour la sante publique. It est d’interet de controler (regulariser) strictement la production du lait de soja et L’assurance de la qualite.

Mots cle: Qualite microbiologiques, lait de soja locale, sante’ publique.