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Objective: Demonstrate the need to use locally generated data in the calibration of a near-infrared spectrometer (NIRS) in order to predict the chemical characteristics of fodder; instead of using data bases from other geographic regions, as is commonly done in Mexico. Design/Methodology/Approach: Two groups of samples collected in prairies of the central highlands of Mexico, the first group was used to calibrate the equipment; the equations generated were validated with a second group, collected in prairies that were different from the ones of the calibration group, but in the same geographic zone. Results: The best regression coefficients of the NIRS predictions, compared to traditional laboratory analyses were for crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), dry matter (DM) and organic matter (OM) (0.93, 0.87, 0.87, 0.56, 0.72 y 0.68 respectively). The lowest predictive value was observed in ashes (0.27). Limitations of the study/implications: The results show the need to use local materials in the calibration process. Conclusions: NIRS will make predictions of their chemical composition, since this is influenced by geographic origin of the sample and its botanical composition

Los quesos tradicionales Zacazonapan tienen características organolépticas únicas y se caracterizan por estar vinculados al territorio de origen. En el proceso de maduración se tienen numerosas variables interactivas que son responsables de los cambios físicos, químicos, biológicos y estructurales. Con el objetivo de evaluar la evolución bacteriológica de quesos artesanales durante su maduración bajo condiciones no controladas en dos épocas de producción, se colectaron muestras de leche cruda y de queso a los 0, 30, 60, 120 y 150 días de maduración. Se determinó la presencia de mohos y levaduras (MyL), bacterias mesófilas aerobias (BMA), Staphylococcus spp. (Staph), coliformes totales (CT), coliformes fecales (CF), Salmonella spp. (Salm) y Listeria spp. (List). La carga microbiana promedio fue 9.68, 9.38, 8.55 y 8.10 log10 UFC/g de queso para MyH, BMA, Staph y CT respectivamente, así como 2.68 log10 NMP/g de queso para CF. No se detectó Salm pero si List. La evolución microbiológica del queso madurado Zacazonapan presentó conteos que superan los niveles máximos de la Norma Oficial Mexicana 243 SSA1 2010.

Small-scale dairy systems require feeding strategies to improve their productivity and sustainability. Since these systems in central Mexico mostly sell their milk to local artisan cheese makers, and cow diets influence milk and dairy products composition, the objective was to evaluate the effect on physicochemical characteristics, sensory appraisal, and economic performance of cheeses made with milk from cows fed different levels of sunflower silage (SFSL) inclusion in the forage DM component of diets (T0 = 0% SFSL; T20 = 20%; T40 = 40%; and, T60 = 60%). Physicochemical composition was analysed by analysis of variance in a completely randomised design and the sensory assessment of the cheeses was with a hedonistic five-point scale and the results were analysed by means of descriptive statistics and a radar graph. Partial budgets were used for economic analyses. There were significant differences (P < 0.05) for all physicochemical variables (moisture content, cheese yield, protein and fat content, and pH) of the cheeses, with higher values for yield, protein and fat content in the treatments that included SFSL. Sensory assessment values were in the average perception range of judges. Treatments that included SFSL had lower production costs, higher margins over costs, and higher returns/costs ratios. It was concluded that the inclusion of sunflower silage in diets for dairy cows in small-scale dairy systems resulted in higher cheese yields, protein and fat content, with positive sensory attributes, lower production costs and higher incomes from cheese making.