| dc.description.abstract | En la cuenca del Río Atoyac en los estados de Puebla y Tlaxcala, se produce leche en sistemas familiares, cuya producción la acaparan intermediarios para elaborar quesos frescos. La calidad de la leche comercializada en este proceso es poco controlada, por lo que el objetivo de este trabajo fue evaluar su características fisicoquímicas y microbiológicas y determinar una posible adulteración. Se analizaron muestras de 264 explotaciones ubicadas en 12 municipios, que forman parte de la cartera de clientes de tres empresas queseras. Se corrieron pruebas presuntivas de plataforma, de sus características físicas: pH, acidez y punto crioscópico, y químicas: grasa, proteína, lactosa, minerales, sólidos no grasos, sólidos totales y contenido de agua. Se realizó un análisis multivariado de agrupación con la técnica Cluster y se realizaron comparaciones entre grupos formados y entre productores por empresas. Adicionalmente se realizaron análisis microbiológicos a 34 muestras. Se formaron cuatro grupos de productores y deja entrever la posibilidad de que uno de ellos adultera con agua y además, adicionan algún compuesto para incrementar el contenido de grasa. Se determinó que existen diferencias significativas (p<0.05) en las características de la leche que comercializan los productores con las empresas. En general es una leche ácida y adulterada fuera de la normatividad, con un promedio de 11.49% de agua que representa una pérdida de $0.67/litro y una dilución de proteína y lactosa. Microbiológicamente, no se encontraron diferencias significativas entre empresas y los conteos de Bacterias Mesófilas Aerobias (BMA), Escherichia coli, Salmonella spp, Hongos y levaduras cumplieron con la norma NOM-243-SSA1-2010, no así para Coliformes Totales, Staphylococcus aureus y Listeria spp. Este estudio sugiere el establecimiento de programas de verificación para el cumplimiento de la normatividad, esperando con ello, que los productores reciban un precio justo de su producción y no tengan necesidad de adulterar la leche. _______________ QUALITY OF MILK PRODUCED IN FAMILY SYSTEMS AND MARKETED IN THE ATOYAC RIVER BASIN IN PUEBLA AND TLAXCALA. ABSTRACT: In the Atoyac River basin in the states of Puebla and Tlaxcala, milk is produced in family systems, whose production is hoarded by intermediaries to make fresh cheeses. The quality of the milk marketed in this process is poorly controlled, so the objective of this research was to evaluate its physicochemical and microbiological characteristics and determine possible adulteration. Samples from 264 farms located in 12 municipalities that are part of the client portfolio of three cheese companies were analyzed. Presumptive platform tests were run; in its physical characteristics, pH, acidity and cryoscopic point were determined; and in its chemical characteristics fat, protein, lactose, minerals, non-fat solids, total solids and water content were determined. A multivariate analysis of grouping was carried out with the Cluster technique and comparisons were made between groups formed and between producers by companies. Additionally, microbiological analyzes were performed on 34 samples. Four groups of producers were defined, one of which hints at the possibility that adulterate the milk with water and add some compound to increase the fat content. There were significant differences (p<0.05) in the characteristics of the milk that the producers market with the companies. In general, it is an acidic and adulterated milk outside the regulations, with an average of 11.49% water, which represents a loss of $0.67/liter and a dilution of protein and lactose. Microbiologically, no significant differences were found between companies and the counts of Aerobic Mesophilic Bacteria (AMB), Escherichia coli, Salmonella spp, fungi and yeasts complied with the NOM-243-SSA1-2010 standard, but not for Total Coliforms, Staphylococcus aureus and Listeria spp. This study suggests the establishment of verification programs for compliance with regulations, hoping with this, the producers receive a fair price for their production and do not have the need to adulterate milk. | es_MX |
