In a microwave safe bowl or large measuring cup, combine the milk, water, and oil. Microwave in 30 second intervals, until the liquid reaches the temperature directed by the yeast manufacturer (120 degrees F to 130 degrees F for Red Star Platinum). Stir the liquid together well before taking the temperature, and for best results, use a digital read thermometer. The liquid should feel hotter than lukewarm, but not so hot that it is uncomfortable or burns.
In the bowl of a standing mixer fitted with the paddle attachment or a large mixing bowl, whisk together the whole wheat flour, all purpose flour, vital wheat gluten flour (if using), brown sugar, yeast salt, and baking soda.
Lightly grease an 8 1/2 x 4 1/2-inch loaf pan with cooking spray. Dust the bottom and sides with cornmeal. Set aside.