Microbiological and physicochemical characterization of a traditionally fermented corn product: "Champús" / Caracterización microbiológica y fisicoquímica de un producto de maíz tradicionalmente fermentado "Champús"

Background: Many native fermented foods in Latin America are made by indigenous communities through processes that preserve their traditions. Among these products is champús, a fermented drink or dessert native to Colombia, Ecuador, and Peru. It has a characteristic flavor between sweet and sour with a low alcohol content, is made from cereals such as corn, wheat, or a mixture of these, and can include fruits and spices. Objectives: This research evaluated the microbiological, physicochemical, and sensory quality characteristics of champús to revalue the consumption of traditional foods. Methods: For this purpose, the microbiological safety criteria, fermenting microorganisms, and physicochemical and sensory parameters were evaluated for two batches of champús prepared by five producers and taking samples at different stages. Results: It was found that the average temperature and relative humidity for processing were between 16.5 ± 2.56 °C and 61.6 ± 9.14 %, respectively, and the products exceeded microbiological criteria such as total coliforms and some microbiological criteria for Escherichia coli and Staphylococcus aureus. There was also a high prevalence of lactic acid bacteria and yeasts throughout the process, with the occurrence of the genera Weissella, Leuconostoc, and Lactobacillus. The presence of organic acids (lactic, acetic, and propionic) and ethanol was evidenced. Champús seems to be a source of calcium, phosphorus, and free amino acids. Conclusions: This information provides a basis to propose improvement plans for small producers and, at the same time, to conduct more detailed studies on the native microbiota of champús

Antecedentes: Muchos de los alimentos nativos fermentados de América Latina son elaborados por las comunidades indígenas mediante procesos que preservan sus tradiciones. Entre estos productos se encuentra el "champús", una bebida o postre fermentado originario de Colombia, Ecuador y Perú. Presenta un sabor característico entre dulce y ácido con un bajo contenido de alcohol, está elaborado a base de cereales como maíz, trigo o la mezcla de estos, y puede llevar entre sus ingredientes frutas y especias. Objetivo: Esta investigación evaluó las características de calidad microbiológica, fisicoquímica y sensorial del champús para revalorizar el consumo de los alimentos tradicionales. Métodos: Se evaluaron criterios de seguridad microbiológica, microorganismos fermentadores, parámetros fisicoquímicos y sensoriales de dos lotes de champús elaborados por 5 productores, tomando muestras en diferentes etapas de proceso. Resultados: Como resultados, se encontró que la temperatura y la humedad relativa promedio de elaboración estuvieron entre 16,5 ± 2,56 °C y 61,6 ± 9,14 % y que los productos superaron los criterios microbiológicos como coliformes totales y algunos criterios microbiológicos como Escherichia coli y Staphylococcus aureus. También hubo una alta prevalencia de bacterias lácticas y levaduras a lo largo del proceso, identificándose los géneros Weissella, Leuconostoc y Lactobacillus. Se evidenció la presencia de ácidos orgánicos (láctico, acético y propiónico) y de etanol. El champús parece ser una fuente de calcio, fósforo y aminoácidos libres. Conclusión: Esta información sirve de base para proponer planes de mejora para los pequeños productores y al mismo tiempo para realizar estudios más detallados sobre la microbiota nativa del champús.

Efficiency of biological treatment for the removal of total and thermotolerant coliform bacteria from domestic sewage / Eficiência do tratamento biológico na remoção de coliformes totais e termotolerantes em esgoto humano

Researchers around the world have focused their efforts on devising combinations of technologies that are not only economically feasible but also effective in mitigating the impacts caused by wastes containing pathogens that pose potential risks to human and animal health. The purpose of this study was to evaluate the performance of a biological treatment system for removing total and thermotolerant coliform bacteria with a view to the possible organic recycling of domestic sewage. To this end, a tubular continuous flow anaerobic digester, with hydraulic retention time (HRT) of 25 days and an optional stabilization pond, were used to treat the sewage produced by 150 people in the municipality of Sertãozinho, SP, Brazil. The samples were collected weekly, always on the same day, at three different sampling points (inlet of the treatment system, the outlet of tubular digester, and the optional stabilization pond), totaling 108 samples. The MPN method was employed to determine the total coliform and thermotolerant coliform populations, using multiple series of three tubes (APHA, 2005). The system proved efficient in reducing the number of indicator bacteria of fecal contamination, showing a removal efficiency of 98.76% for total coliforms and of 99.29% for thermotolerant coliforms. However, a third treatment step involving polishing should be included to render the effluent suitable for use in fertigation or discharge into water bodies.

Aliar tecnologias que sejam viáveis e ainda eficientes em mitigar o impacto gerado pelos resíduos, que possuem potencial patogênico à saúde humana e animal, tem sido o propósito das ações de pesquisadores em todo o mundo. Dessa forma, objetivou-se avaliar um sistema de tratamento biológico, quanto a redução de coliformes totais e coliformes termotolerantes, visando a possibilidade de reciclagem orgânica do esgoto doméstico. Para tanto foi utilizado um biodigestor tubular de fluxo contínuo com tempo de retenção hidráulica (TRH) de 25 dias e uma lagoa de estabilização facultativa, responsável pelo tratamento de esgoto produzido por 150 pessoas, no município de Sertãozinho/SP. As amostras foram colhidas, semanalmente e sempre no mesmo dia, em três pontos distintos de colheita (entrada do sistema de tratamento, saída do biodigestor tubular e na lagoa de estabilização facultativa), totalizando 108 amostras. Para as determinações das populações de coliformes totais e termotolerantes foi utilizada a técnica do NMP em tubos múltiplos série de três tubos (APHA, 2005). O sistema foi eficiente quanto a redução no número de micro-organismos indicadores de poluição fecal atingindo 98,75% para coliformes totais e 99,26% para os termotolerantes. Entretanto, deve ser prevista mais uma etapa para polimento do efluente dando condições para sua utilização na fertirrigação ou lançamento em corpos de água.

Aspectos fundamentales sobre el género Enterococcus como patógeno de elevada importancia en la actualidad / Fundamental features on he Enterococcus genus as a very important pathogen at present time

En los últimos años el género Enterococcus ha cobrado una gran importancia al nivel internacional por su elevada incidencia en las enfermedades nosocomiales y por la adquisición de resistencia a muchos antimicrobianos. De igual manera, son considerados indicadores de la inocuidad de los alimentos, pues debido a su amplia distribución, pueden encontrarse en estos productos y sobrevivir a los procesos de tratamiento a que son sometidos, por su elevada resistencia a condiciones adversas. Igualmente, se encuentran dentro del grupo de microorganismos indicadores de contaminación fecal de las aguas, y se consideran como el indicador más eficiente para evaluar la calidad del agua de mar para uso recreativo. Aunque en Cuba existen algunos reportes de aislamientos de estos microorganismos en la clínica, el diagnóstico en este sentido aún es insuficiente, también es escasa o nula la búsqueda de estos microorganismos en aguas y alimentos, por lo que resulta imprescindible realizar una revisión bibliográfica sobre esta temática. El objetivo de esta primera revisión consiste en profundizar en los aspectos fundamentales sobre el género Enterococcus.

In the last years Enterococcus genus has gained in relevance due to its high incidence in nosocomials illnesses and resistance acquisition to many antimicrobials agents. These microorganisms are considered indicators of the food inocuit due to their wide distribution, their presence in products and their ability to survive different processes and their high resistance to adverse conditions. Simillary, they are considered as indicators microorganisms of fecal contamination of water, being considered as the most efficient parameter to evaluate the quality of recreational seewater. Although in Cuba exist some reports about the isolations of these microorganisms in the clinic, the diagnosis is still insufficient. Also is poor or null the search of these microorganisms in waters and foods, therefore it is indispensable to carry out a review on this matter. The objective of this first revision consists on approaching the more fundamental aspects related with Enterococcus genus.

Water quality in a lagoon in the southeast pampa region of Argentina / Calidad del agua en una laguna del sudeste pampeano (Argentina)

This work evaluates the chemical and bacteriological qualities of the recreational waters of the Sauce Grande lagoon (Argentina). Samples were taken between March 2002 and December 2003. Ninety-six samples from three sampling stations were analyzed in order to determine the density of aerobic heterotrophic microorganisms, the presence of sulphite-reducing clostridia, and the most probable number of total coliforms, E. coli, fecal enterococci and P. aeruginosa. The water pH, temperature and chemical composition (N-NO3-, PO4³-, Na+, Ca++ +Mg++, EC and SAR) were also determined. Statistical analysis shows an increase in the microbial parameters of fecal pollution and in the population of heterotrophic microorganisms during the warmest months, influenced by higher temperatures and the more intensive recreational use. Bacterial count indicated that fecal pollution was statistically lower at the recreational area monitoring station; however, P. aeruginosa, an opportunistic pathogen, was present in higher than permitted densities in all determinations. These results show that, from the physico-chemical point of view, anthropogenic activities do not significantly affect the quality of the resource.

En el presente trabajo se evaluó la calidad bacteriológica y química en aguas de la laguna Sauce Grande (Argentina). Los muestreos fueron realizados entre marzo de 2002 y diciembre de 2003. Se analizaron un total de 96 muestras provenientes de tres estaciones de monitoreo, determinando: densidad de microorganismos heterótrofos mesófilos, presencia de clostridios sulfito-reductores y número más probable de coliformes totales, Escherichia coli, enterococos fecales y Pseudomonas aeruginosa. También se efectuaron determinaciones de pH, temperatura del agua y composición química (N-NO3-, PO4(3-), Na+, Ca++ + Mg++, CE y RAS). Se observó que en los meses más cálidos se produjo un aumento en los parámetros microbianos indicadores de contaminación fecal y en la población de microorganismos heterotrófos; dicho comportamiento estaría influenciado por el aumento de la temperatura y el mayor uso recreativo del recurso. El recuento de bacterias indicadoras de contaminación fecal fue menor en la estación de monitoreo donde se encuentra ubicado el balneario; no obstante, P. aeruginosa, patógeno oportunista, estuvo presente en todas las determinaciones con densidades mayores a los valores permitidos. Desde el punto de vista fisicoquímico, no hay un aporte antropogénico significativo de contaminantes que afecten la calidad del recurso.