Reward devaluation is the process by which the perceived reward value of food decreases as one eats.

“and so reward evaluation is like you know if you haven't eaten for a day and you see like a pizza someone brings a pizza in front of you it just looks delicious that First Slice tastes amazing it's salty it's fatty it's delicious you eat five of those slices it feels greasy and nasty and so that process of how you perceive the food and its reward salience degrades as you eat and as your brain basically shifts into a thing of we don't need to consume calories and food anymore we're okay we're full now”