Functionality and Organoleptic Properties of Maize Tortillas Enriched with Five Different Soybean Proteins

Soybean proteins are ideally suited to enhance the essential amino acid balance of cereal-based foods. The aim of this investigation was to assess the functionality of different soybean proteins in maize tortillas with yield and with sensorial and textural shelf-life characteristics as criteria to select the best supplement. Four different defatted soybean flours (SBF1, SBF2, SBF3, and SBF4) and one soybean protein concentrate (SBC) were added to increase protein content of dry masa flour between 25 and 30%. The evaluated soybean ingredients displayed urease activity of 0.1-2.25, water absorption index of 4.02-8.34, protein dispersibility index of 23-75%, and fat absorption index ranging from 2.5 to 3.1. Moisture, crude protein, crude fat, and rollability were not different among enriched tortillas, but maximum force after five days of storage was higher for SBF1 and lower for SBF 3. The control and SBF1 followed by SBC were the best evaluated overall according to the most relevant parameters for consumers and producers. Correlation analyses displayed a negative association among yield-related parameters and protein dispersibility index, urease activity, and water solubility, opposite to the relationship for texture-related properties. The best soybean proteins to be used in maize tortilla supplementation should have, preferably, reduced water solubility, urease activity, and protein dispersibility index.