Characterization, functionality and in vitro digestion of refined starches from ten chickpea cultivars. A. MILÁN NORIS (1), S. Serna-Saldivar (1), J. De la Rosa-Millan (2) (1) Tecnologico de Monterrey, Monterrey, Mexico; (2) Tecnologico de Monterrey, , Mexico.
Chickpea (<i>Cicer arietinum</i> L) is an important legume crop in the world and its main carbohydrate is starch (38-50%). Viscous characteristics (analyzed by RVA) and digestibility properties (by the <i>in vitro</i> Englyst assay to determine the rapidly, slowly and resistant starch fractions) of wet milled isolated starch from eight pigmented and two cream chickpeas were investigated. The chickpeas studied had green (1 cv), black (3 cv), red (3 cv), brown (1 cv) and cream (2 cv) colored seed coat. The yield in chickpea starches ranged from 19-30%, in which starch and amylose content varied from 87-96% and 25-35%, respectively. The viscous characteristics of 13% (w/v) aqueous starch dispersions showed significant differences among the samples, their pasting temperatures ranged from 70-76ºC, the highest for Br3512 and the lowest for C3421. The R5383 starch showed the highest viscosity values, compared with their counterparts; moreover, the peak and final viscosities showed strong positive correlations with amylose (<i>r</i>=0.8667, <i>p</i>=0.0012 and <i>r</i>=0.9213, <i>p</i>=0.0002). Resistant starch (RS) fraction was higher in R14782 starch (52%) and lower in R13124 starch (42%). The rapidly digestible starch (RDS) and slowly digestible starch (SDS) fractions varied from 17% (R14782) to 29% (R13124) and 27% (R13124) to 36% (R5383), respectively. The predicted glycemic index (pGI) in chickpea starches ranged from 48-49%, in which the R5383 starch showed the lowest pGI that could be associated with its higher amylose content (<i>r=-0.6860, p=0.0282</i>) and final viscosity (<i>r</i>=-0.6418, <i>p</i>=0.045). Overall, the results suggest that the isolated starches from pigmented chickpeas may hold a potential for the development of functional foods regarding their low glycemic index and viscous properties.
|