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A. LOREDO, Univ. Autonoma de Coahuila, Food Research Dept. School of Chemistry, PO Box 252, Saltillo, Coahuila, 25000, Mexico, C. N. Aguilar, Univ. Autonoma de Cohuila, Food Research Dept., School of Chemistry, Saltillo, Coahuila, 25000, M. L. Reyes-Vega, Food Research Dept., Univ. Autonoma de Coahuila, Blvd. V. Carranza s/n, 25280 Saltillo, Coahuila, 25280, Mexico, R. Rodriguez-Herrera, Food Research Dept., School of Chemistry., Univ. Autónoma de Coahuila, PO Box 252, Saltillo, Coahuila, 25001, Mexico, J. C. Montanez, Coyotefoods, Biopolymer and Biotechnology Co., Research and Development Center, Simon Bolivar 851A, Saltillo, 25000, Mexico, A. Ocampo-Ramírez, Univ. Autonoma de Coahuila, Food Research Dept., School fo Chemistry, PO Box 252, Saltillo, Coahuila, 25000, Mexico, A. V. Charles-Rodríguez, Univ. Autonoma de Coahuila, Food Research Dept., School of Chemistry, PO Box 252, Saltillo, Coahuila, 25000, Mexico, and J. C. Contreras-Esquivel, Food Research Dept., School of Chemistry, Univ. Autónoma de Coahuila, PO Box 252, Saltillo, Coahuila, 25000, Mexico. Chitosan-oligosaccharides have become relevant in the last year due to their properties as antimicrobial, enhancing the immune system and fat absorption, among others. In Mexico, the shrimp industry wastes are an important source of chitosan, besides, in commercial corn tortillas only artificial preservatives are used, which does not fit with the actual tendency of consuming natural products. In this work, the antifungal capacity of these oligosaccharides obtained enzymatically was evaluated as preservative in corn tortillas. The chitosan was degraded using a bacterial endo-chitosanase in five series (2, 4, 8, 14 h). The enzyme was inactivated heating the solution, then dialyzed and lyophilised. The fungal inhibition was tested in agar plates. After that, corn tortillas were prepared using the powder obtained at 4 h of enzymatic degradation. The tortillas were packed in sterile plastic bags and incubated at room temperature. These tortillas were then analyzed for detection of filamentous fungi each 5 days. Also, a sensory analysis was realized at day zero. All chitosan-oligosaccharides series were totally water soluble, except for that obtained at 2 h of enzymatic degradation. Of the fungal inhibition tests in agar plates, the most effective hidrolysate was the one obtained at 4 h of reaction (10 mm less of growth of Aspergillus compared with the blank). It was observed in corn tortillas important inhibition of fungal grow: 94000 UFC less in the tortillas with chitosan-oligosaccharide. The sensory analysis did not show significant differences. These results show that the chitosan-oligosaccharides can be used as fungistatic in corn tortillas without altering the organoleptic properties and increase their nutraceutical value.
Session 35, Nutraceutical & Functional Foods: General I
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |