What causes a food to become tough as opposed to crispy or flaky when pan frying or baking?

Question

When making dosa or pizza, I like to try to get the dosa or pizza crust to be crispy, so I often cook or bake a bit longer. I can achieve crispiness, but it seems to come at the expense of making them "tough," as in a bit hard to chew.

Here's my dosa recipe:

• 2 cups (412g) urad dal
• 4 tbsp (52g) chana dal
• 2 tsp (6g) methi (fenugreek) seeds
• 6 cups (1226g) sona masuri rice
• 1/2 cup (58g) poha
• 1 tbsp kosher salt (must be non iodized)
• 5 cups water to blend dal
• 2 cup water to blend rice

What is the science behind why this happens and how do I avoid it?

Answer 1

The Maillard reaction. Chemical reaction between amino acids and simple sugars at high temperature.

To keep the inner part soft, you expose food to high (but not too high) temperature just enough time to make crust crispy.

If you underexpose or the temp is too low, your food is undercooked.

If the temperature is too high and you overexpose, you get burnt food.

If the temperature is too low and you overexpose (likely your case), you get crispy crust and «tough» guts, due to a) too much water being lost and b) internals being overcooked.

For bread/pizza, proper pizza stone is essential. Depending on wheat type, dough and baking process, you have to preheat your oven together with your stone to 200-300°C. Stone works like a heat accumulator, keeping the temperature even, not too high/too low.

When they bake bread in tandoor, there's up to 450°C inside the oven, but bread bakes just perfectly fine - in just a minute or two.