71A-42 |
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E. PAZ-GAMBOA1, E. Herman-Lara2, C. E. Martínez-Sánchez1, H. Nogueira-Terrones1, M. Montero-Lagunes3, C. Antonio-Estrada1, J. Acevedo-Acevedo1, O. Acevedo-Vendrel1, and J. Sanchez-Burgos1. (1) Biochemical Engineering Dept., Instituto Tecnologico de Tuxtepec, Calz. Dr. Vìctor Bravo Ahuja s/n, Col. 5 de Mayo, Tuxtepec, Oax., 68360, Mexico, (2) Chemical and Biochemical Dept., Instituto Tecnológico de Tuxtepec, PO Box 69, Tuxtepec, Oax., 68360, Mexico, (3) Campo Experimental "La Posta", INIFAB, Paso del Toro, Veracruz, Ver, Mexico The oaxaca-type cheese is one of the cheeses of greater consumption in our state and has been accepted in different parts of the country and the world. Nevertheless, its short shelf life (1 to 2 wk) is worrisome for the producers, since this condition strongly affects its transport and commercialization. For this reason and in order to increase its shelf life, we proposed the use of a natural preservative (nisin) and a nonnatural one (potassium sorbate) to different concentrations added to the cheeses during its manufacture. Seven treatments were used: two with addition of nisin, two with potassium sorbate, two with both of them at different concentrations, and a control without preservative. Physicochemical analyses were determined according to AOAC, Mexican norms were used for the microbiological analysis, and a sensory panel was trained during 16 wk to evaluate the cheeses. Physicochemical analyses did not show significant differences between cheeses treated and the control; moreover, these studies indicated that the combination of nisin 10 ppm - sorbate 0.05% in a 50/50 ratio is an alternative for the reduction of contamination by yeasts, Staphylococcus aureus, and coliform count, at refrigeration temperature of 6 °C and extending the shelf life up to 25 to 30 days in comparison with the control, which had a shelf life of only 15 days. Also, the samples with additives showed significant sensory differences in reference to the control. Treated samples were spongier and with a good fiber formation, whereas the control was drier and harder. With the data obtained, it was possible to observe that the use of additives confer some favorable attributes to the cheeses, and they were well accepted for the consumers.
Session 71A, Dairy Foods: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |