The two lectures talked about different opinions about the first grain-based food human has ever discovered, the reading material thinks that bread is the first grain-based food, while the listening lecture thinks that beer is the first grain-based food.
Firstly, according to the reading material, humans discovered that grinding wheat can make it easier to eat. However, the listening lecture claims that you don't need to rub it, just keeping the grain in a moist environment can make it sprout, which is easier to happen.
Secondly, the reading material states that getting the simplest bread only needs humans to bake it with fire, baking the wheatpaste makes it store for a longer period. On the other hand, the listening lecture disputes that firing wheatpaste is not an obvious way for ancient people to find it.
Finally, the reading material reports that putting the wheat in a natural environment makes it ferment, and humans find that it's lighter and easier to eat after baking. On the contrary, the listening lecture disagrees that when fermenting wheat, it is more obvious for humans to see the bubbles and experiment by tasting them, then discover beers.