The effect of different nixtamalisation processes on some physicochemical properties, nutritional composition and glycemic index Rosa María Mariscal Moreno a , J.D.C. Figueroa a, * , David Santiago-Ramos b , Ger  onimo Ar  ambula Villa a , Sergio Jim  enez Sandoval a , Patricia Rayas-Duarte c , Jos  e Juan V  eles-Medina a ,H  ector Eduardo Martínez Flores d a CINVESTAV-Unidad Queretaro, Libramiento Norponiente No. 2000, Fracc Real de Juriquilla, Queretaro, Qro 76230, Mexico b PROPAC, Universidad Aut onoma de Queretaro. Cerro de las Campanas S/N, Col. Las Campanas, Queretaro, Queretaro C. P. 76010, Mexico c Robert M. Kerr Food & Agricultural Products Center, Biochemistry and Molecular Biology, Oklahoma State University, 123 FAPC, Stillwater, OK 74078-6055, USA d Facultad de Químico Farmacobiología, Universidad Michoacana de San Nicol as de Hidalgo, Tzintzuntzan 173, Col. Matamoros, Morelia Mich., Mexico article info Article history: Received 24 March 2015 Received in revised form 24 June 2015 Accepted 28 June 2015 Available online 2 July 2015 Keywords: Nixtamalisation Resistant starch Chemical composition Glycemic index abstract The objective was to evaluate corn tortillas made from three nixtamalisation processes including Traditional with lime (TNP), Classic with ashes (CNP) and Ecological with Ca salts (ENP), and their effect on mineral content (Ca, Fe, K, and Mg), chemical composition, resistant starch (RS), and glycemic index (GI). ENP with calcium propionate and carbonate had higher fat values than tortillas from CNP. EPN and CNP presented the higher dietary fibre, explained by the highest pericarp retention. In TNP the pericarp and external layers were lost during the cooking, steeping and washing steps and had lower crude fiber. The amount of RS increased in nixtamal and tortillas independently of nixtmalisation processes. Annealing of starch was shown by the increase of onset, peak and final gelatinisation temperatures in nixtamalised products compared with untreated maize. Gelatinisation was higher for calcium propionate ENP and 1% ash CNP. Native maize changed from A-type to V-type pattern in nixtamalised products denoting the formation of amylose-lipid complexes. Overall, nixtamalisation processes and salts used increased RS. The GI was affected by chemical composition in tortillas and amount of RS. Tortillas made from ENP Ca propionate and ENP 1% ash CNP can be classified as low GI foods. © 2015 Elsevier Ltd. All rights reserved. 1. Introduction Maize for human consumption is processed in Mexico following the pre-Columbian technique known as nixtamalisation which is a process whereby maize is boiled in water containing Ca(OH) 2 (lime), the nixtamal (cooked maize), obtained is steeped overnight, washed and ground to obtain masa. The masa can be used imme- diately for tortillas, or dried and grounded to produce dry masa flour (nixtamalised flour). The nixtamalisation process is critical in enhancing the nutritional value of maize and is used to make several products (tortillas, tamales, pozole, atoles, totopos, snacks, tacos, tostadas, and nachos) which are staple foods in Mexico, Central America and widely consumed in United States (Campechano et al., 2012; Figueroa et al., 2013). Archeological evidence suggests that the ancient nixtamalisa- tion process (Classic Nixtamalisation Process, CNP) used by the Mayas in the Preclassic period (1200-250 B C.) consisted in cooking maize with wood ashes (Katz et al., 1974). Later the Aztecs, settled in central Mexico around 1325 A.D. substituted ashes for lime, though it is not clear exactly when, creating the Traditional Nix- tamalisation Process (TNP) that is remained used in present com- mercial operations. There is a need to improve the sustainability of the TNP which uses large volume of water producing high dry matter losses (3e15%) in the nixtamal during the cooking and washing steps (Campechano et al., 2012). During the mentioned processing * Corresponding author. E-mail address: jfigueroa@qro.cinvestav.mx (J.D.C. Figueroa). Contents lists available at ScienceDirect Journal of Cereal Science journal homepage: www.elsevier.com/locate/jcs http://dx.doi.org/10.1016/j.jcs.2015.06.016 0733-5210/© 2015 Elsevier Ltd. All rights reserved. Journal of Cereal Science 65 (2015) 140e146