18A-14

E. CAMPECHANO- CARRERA¹, F. Pereira-Pacheco², D. Betancur-Ancona¹, A. Corona-Cruz², and E. Polanco-Lugo². (1) Food Science and Technology, Univ. Autonoma de Yucatan, Av. Juárez No. 421 Cd. Industrial Mérida, Yucatán, Michoacan No. 3, Loma Bonita, 68400, Mexico, (2) Food Science and Technology, Univ. Autonoma de Yucatan, Av. Juárez No. 421 Cd. industrial Mérida, Yucatán, Mérida, Yucatán, 97288, Mexico

Starch is the main energy source in the human diet and it is a valuable resource in the formulation of food products, because it allows the use of modification techniques to develop ingredients with diverse functionality such as resistant starch (RS). In the manufacture of materials that show adequate functional properties for a nutritious system, polysaccharide and non polysaccharide components are found in some varieties of leguminous grains that can show a dietary fiber behavior. In this study, the hydrothermal effect in the formation of RS in Phaseolus lunatus (Pl) and Vigna unguiculata(Vu) starch was evaluated. A factorial 2³ design was used in which the factors were the starch concentration (10 and 30%), the gelling temperature (80 and 90° C) and the processing time (30 and 60 min.). The content of RS was used as a response variable. In both species with the low starch concentration treatment (10%), low temperature (80°C) and shorter processing time, a value greater than RS was obtained with 14.05% in Vu and 26.96% in Pl. These values were statistically different from the other treatments (P>0.05). The highest content of RS in both legumes was in Pl, possibly because the complete gelling temperature was reached, which is 80 °C; the difference of the RS content in Vu could explain through the physical and molecular characteristics of each species, as it has been pointed out that the formation of RS is totally dependent of the botanic origin. On the other hand, the formation process of RS was apparently related to a greater availability of water in the media which together with the temperature facilitated amylose solubility due to hydration. In Pl, the amylase content is 32.7%; due to that, a greater quantity of RS was obtained because the amylose content and RS generation is correlated in a positive manner.

Session 18A, Carbohydrate: General
2:00 PM - 5:30 PM, Sunday PM Room Hall I-2

2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana