Production of low-fat tortilla chips using alternative methods of drying before frying

Abstract

Tortilla chips were prepared from commercial nixtamalized dry masa flour. They were baked, sun dried and then fried in fresh soybean oil. Control chips were not sun-dried before frying. A commercial batch fryer was used. The effect of solar drying of the tortilla chips on the rate of moisture loss, oil absorption, texture, microstructure, and the physical properties of tortilla chips during and after drying was analyzed. The results indicated that the final oil content of the sun-dried tortilla chips was significantly lower than the control treatment. As a result of solar drying, the structure of the tortilla chips was tighter before frying, but expanded significantly during frying. The difference in the temperature profile at the center of tortilla chips during frying was analyzed. The results showed a clear difference in the length of the plateau, and the boiling point of water during the frying process, Tortilla pieces were also prepared from nixtamalized masa flour, and dried under impinging hot air. The effect of different drying conditions on the drying rate, texture, shrinkage profile and microstructure was analyzed. The results indicated that I drying rate was mostly affected by the air temperature, texture was crispier at higher air temperatures; shrinkage of the piece was higher at lower convective heat transfer coefficient, and microstructure looked smoother at higher air temperature A process to produce low-fat tortilla chips with good flavor and texture using convection-oven-baking, air impingement drying and frying was suggested and validated.