Study and evolution of the quality of raw milk from dairy farms in the northwest of the province of Santa Fe and south of the province of Santiago del Estero, Argentina (1993 – 2009)

Received August 12th 2010 // Accepted April 11th 2011 // Published online June 08th 2011

REVELLI, G.R.1; SBODIO, O.A.2; TERCERO, E.J.2

Abstract
A total of 10,704 raw milk samples from a bulk tank were collected on 55 dairy farms associated to the Cooperativa Tambera y Agropecuaria Nueva Alpina Ltda. between 1993 and 2009. Physicochemical, microbiological and sanitary parameters were analyzed within the framework of the Comprehensive Milk Quality Improvement Program to determine the mean values that characterize the zone. The following values were found: Acidity: 16.30 ± 0.96 °D, pH: 6.68 ± 0.04, Fat: 3.48 ± 0.24%, True Protein: 3.11 ± 0.12%, Lactose: 4.74 ± 0.16%, Ash: 0.70 ± 0.09%, Total Solids: 12.18 ± 0.42%, Freezing Point: -0.530 ± 0.02 °C, Total Bacterial Count: 9.6 x 104 ± 2.2 x 105 CFU/ml, Somatic Cell Count: 407,000 ± 230,000 cells/ml and Antibiotic Residues: 99.64% Negative. The most significant correlations were: Fat vs Total Solids (r = 0.784; P < 0.001) and True Protein vs Total Solids (r = 0.557; P < 0.001). The compositional quality of raw milk from dairy farms in the northwest of Santa Fe and south of Santiago del Estero were studied over a period of 17 years and showed a significant improvement, particularly regarding the indicators that infer a high industrial value. Optimization of the producers’ management capacity and the operational quality of dairy farmers contributed to achieve these results.

Keywords: lactology, zonal characterization, comprehensive training.

1 Laboratorio Integral de Servicios Analíticos (L.I.S.A.), Cooperativa Tambera y Agropecuaria Nueva Alpina Ltda., S2340ALB Ceres, Santa Fe, Argentina. E-mail: lisa@cotana.com.ar
2 Instituto de Tecnología de Alimentos (I.T.A.), Facultad de Ingeniería Química, Universidad Nacional del Litoral, Casilla de Correo 266, Santa Fe, Argentina.