QUALITY OF GRAIN AND TORTILLA MADE WITH LOCAL MAIZE LANDRACES FROM THE HIGH VALLEYS AND THE VALLEY OF MEZQUITAL, MÉXICO

Abstract

In the State of Hidalgo, México, around 200 thousand hectares of maize (Zea mays L.) are grown under rainfed conditions; 95 % of which are local landraces. This study was conducted to evaluate grain and tortilla quality of 26 maize landraces from the High Valleys and Valley of Mezquital, Hidalgo, México, and to identify outstanding races for the maize dough and tortilla industry. These accessions include the races Elotes Cónicos, Chalqueño, Cónico, Tuxpeño, Arrocillo, Celaya, Tabloncillo, Ratón, Pepitilla, Cacahuacintle, Palomero Toluqueño, Olotillo, Elotes Occidentales, Cónico Norteño and Bolita. Analysis of variance revealed significant differences (P ≤ 0.05) in all of the variables analyzed. Races preferred by farmers were Cónico (32 %), Chalqueño (20 %) and Elotes Cónicos (18 %). There was a wide range of colors (black, red, yellow, spotted and white), sizes (large, medium and small), and textures (very soft, soft, medium and hard), as well as high percentages of pedicle and pericarp and low proportions germ. Some of these variables limit processing in maize dough-tortilla mills. The Cónico, Chalqueño, Tuxpeño, Cónico Norteño, Olotillo, Pepitilla and Celaya races, which have white grain and soft and medium texture, yielded the best quality tortillas with the highest moisture content (40.3 %), the highest maize dough/kernel ratio (2.0:1.1) and the highest tortilla/kernel ratio (1.4:1.1); little force was required to break the tortillas (soft) (< 180 gf), but the required force increased significantly (P < 0.05) after storage for 24 h at 4 °C ( x = 191.4 gf). These tortillas had a luminous appearance (L* = 71.8 %), with no observable changes during storage (71.5 %).