Exploring the influence of wood ash, maize cob ash, and tequesquite (alkaline rock) on nixtamalization of maize

Nixtamalization, an ancient process vital for maize processing, enhances maize's nutritional value, texture, flavor, and shelf life while reducing mycotoxin contamination, making it a cornerstone technique in maize processing with both nutritional and food safety implications. Initially performed with ashes, modern nixtamalization relies on food-grade calcium hydroxide or calcium oxide (lime). However, regions lacking lime deposits or processing technology necessitate alternative nixtamalization options for sustainable maize processing. This study aimed to assess the mineral composition of alkaline rocks (tequesquite) and two types of ash (wood and maize cob) and determine the optimal cooking conditions to achieve tortillas comparable to those made from lime-nixtamalized maize. Different ash and tequesquite concentrations (5%, 10%, and 15%) were tested with nixtamalization durations of 40, 50, and 60 min. Quality parameters of nixtamal and tortillas were evaluated. Data were analyzed using a completely randomized design with Tukey's comparison of means (p ≤ 0.05) and principal components analysis. Results revealed potassium as the predominant element in the ash, while sodium prevailed in tequesquite. Although significant differences were observed in nixtamalization variables, tortillas made with 5% maize cob ash or tequesquite closely resembled those treated with lime in terms of quality parameters.