Water amount and temperature are critical for both corn and flour tortilla processing. Dough (masa) water content and temperature affect the rate of hydration, mixing time, functionality of gums, starch, leavening acids, proteins, and the rheology (texture) of the mixture. Dough temperatures for flour tortillas vary widely (70 – 110ºF) but are commonly held to 88 – 95ºF for press lines and lower temperatures (70 – 90ºF) for hand-stretch and die-cut operations. Increasing dough temperatures can reduce mixing time roughly 4 minutes per 10 degrees Celsius increase in temperature. Increasing dough temperature also reduces leavening effectiveness and care must be taken not to overheat the dough. Dough temperatures for recently ground nixtamal may range from 100-130ºF, while those prepared from nixtamalized corn flour (or dry masa flour) range from 70-110ºF. Dough temperature can be controlled by varying the water temperature, length of mixing, tightness of the mill stones, and/or the speed of the mixer. Charts are available for most mixers to calculate the final dough temperature. Generally a pocket thermometer and an experienced operator generate dough with consistent temperatures. Several things should be recorded at the mixer including the amount and temperature of the water, the room temperature, the dough temperature, and mixing times and speeds. All of these things affect the dough temperature. Variations in amount of water in the dough and dough temperature impact performance of the dough through the sheeter, divider, rounder, hot-press and/or oven. Consider dough temperature like a doctor thinks of a patient’s temperature. Dough temperatures 3-4ºF degrees from the “normal” temperature indicate problems.