Bacterias ácido lácticas nativas como cultivo iniciador para la elaboración de queso crema mexicano

espanolIntroduccion. Los cultivos bacterianos iniciadores son empleados exitosamente en la elaboracion de quesos artesanales, ayudan a mantener las caracteristicas sensoriales sui generis, ademas, controlan la presencia de patogenos. Se ha reportado que las cepas nativas son las mejores opciones para realizar esta funcion. Objetivo. El objetivo de la presente investigacion fue evaluar el efecto de la adicion de bacterias acido lacticas (BAL), aisladas del proceso artesanal de elaboracion de queso como iniciadoras en la elaboracion de queso crema a partir de leche pasteurizada. Materiales y metodos. El trabajo se realizo en la region de Ocosingo, Chiapas, Mexico, durante los meses de febrero a noviembre del ano 2016. Se aislaron 37 cepas de diferente morfologia, provenientes de leche, queso y suero, de las cuales 21 fueron Gram positivas, catalasa y peroxidasa negativas. Por su capacidad acidificante, se seleccionaron ocho cepas con las cuales se formularon seis tratamientos (combinaciones de tres cepas). Resultados. El tratamiento que sensorialmente fue mas aceptado por los consumidores, se reestructuro en tres nuevos tratamientos (tres combinaciones de dos cepas). De estos nuevos tratamientos, aquel (T8) donde se combinaron dos BAL (2S y 30Q) fue similar en color, firmeza y contenido de grasa al testigo (queso crema elaborado con leche sin pasteurizar). Fueron ligeramente diferentes en el contenido de proteina, humedad y cenizas, sin embargo, los panelistas expertos no encontraron diferencias (prueba de discriminacion A no A) significativas entre el queso crema T8 y el testigo. Este mismo tratamiento promovio en el queso crema recuentos microbiologicos (mesofilos aerobios, coliformes totales, mohos y levaduras) inferiores a las establecidas por las normas sanitarias. Conclusion. El uso de las BAL 2S y 30Q como cultivo iniciador permitio obtener un queso crema a partir de leche pasteurizada con caracteristicas similares al queso crema tradicional, pero que resulto microbiologicamente inocuo. EnglishIntroduction. The bacterial starter cultures are successfully used in the production of artisan cheeses, since they help to maintain sui generis sensory characteristics, as well as controlling the presence of pathogens. It has been reported that natives strains are the best options to perform this function. Objective. The aim of this research was to evaluate the effect of the addition of lactic acid bacteria (LAB) isolated from the traditional process of cheese making, as a starters in the manufacture of cream cheese from pasteurized milk. Materials and methods. The research was done in the Ocosingo city, Chiapas, Mexico, during the months of February to November from 2016. 37 strains with different morphology were isolated, from milk, cheese and whey, of which 21 were Gram positive, catalase and peroxidase negative. For their acidifying capacity, eight strains were selected, with which six treatments were formulated (combinations of three strains). Results. The treatment that was most accepted by consumers was restructured into three new treatments (three combinations of two strains). Of these new treatments, that one (T8) where two LABs (2S and 30Q) were combined was similar in color, firmness and fat content to the control (cream cheese made with unpasteurized milk). Although they were slightly different in protein, moisture and ash content, however, expert panelists found no significant differences (proof of discrimination A not A) between the T8 cream cheese and the control. This same treatment promoted microbiological counts (aerobic mesophilic, total coliforms, and molds and yeasts) lower than those established by the sanitary standards. Conclusion. The use of BAL 2S and 30Q as starter culture allowed a cream cheese to be obtained from pasteurized milk with similar characteristics to traditional cream cheese, besides microbiologically safe.