Modeling the structural changes of tortilla chips during frying

摘要

Monte Carlo simulation was used to model structure changes in tortilla chips during frying. The results were analyzed using Ensight~(TM) (CEI, Morrisville, NC), a Scientist's, plotting tool. Cluster identity (oil, water, air, solid), number of clusters, cluster size, and mean size were determined. Cluster statistics were further provided for different frying conditions. The model predicted maximum oil absorption in a control tortilla chip during the first 10 s of frying, which coincided with maximum water evaporation also observed during the first 10 s of frying. Maximum pore expansion occurred between 30 and 40 s of frying. Steam baking the tortilla chip prior to frying caused the formation of a tight barrier on the surface due to starch gelati-nization. This surface prevented water evaporation as well as oil absorption. Higher initial moisture contents provided for an increasing porosity in the product, from 47.12% to 54.04%. Freeze-dried tortilla chips had higher internal oil content because smaller pores spread over the matrix provide a larger surface area and higher capillary pressures. The smaller pores are due to the absence of a tight barrier along the tortilla's surface, as freeze-drying does not cause starch gelatinization (no heat treatment prior to frying).