A dazzling light stung his eyes.

He tried to close his eyes but found that he had no light-sensitive organs at all.
"I am ...... who? Where am I?"
Countless questions were waiting to be addressed, but he was unable to make a sound.
Looking around, he found himself immersed in a sea of white
"Is this ...... milk?"
After a few moments, he realized that it was the interior of a glass room.
"Calm down, who am I and what am I really?"
This didn't provide any help, as he found himself unable to pull up any memories. The only thing he was sure of was his presence, simply because he was thinking.
He began to use the exclusion method to determine what he was,
Some kind of little bug? He couldn't sense the presence of any organ.
A virus? A bacterium? Possibly, but ......
Protein?
Protein.
It's unbelievable. A protein that can think and has common sense?
Not even a living thing, but somehow able to sense the outside world?
Without leaving it much time to think, a huge hand reached out and lifted up the equally huge glass room.
"I know, I'm the protein in the milk, this glass room is the glass that holds the milk, and I'm about to be drunk!"
Like a tsunami, the protein is swept up by countless water, protein, fat and lactose and pushes deep into the throat.
"Proteins have four levels of structure and have to unravel the peptide chain before it can be digested, I should still be intact at the oral stage." The protein thought as it was warmed by the temperature of the mouth.
It found that the nearby salivary amylase was indeed indifferent to him, and looking up, a huge sling hung above the mouth
“That’s uvula which use to keep food out of the nasal cavity? It's spectacular."
The protein enters the esophagus and makes its way toward the stomach, and in addition to gravity dragging it down with the rest of the milk, other muscles in the esophagus are moving around to try to speed up the process.
With a thud, the protein falls into the gastric juices and it feels a twinge of nervousness because it knows that pepsin is coming, and the stomach acid makes the protein start to feel like it is undergoing subtle changes.
Nearby pepsin is activated and starts to digest the protein.
The protein does not feel pain but feels that part of itself is turning into amino acids. Little by little, time passes, and before the protein is completely digested into amino acids, it goes to the small intestine with the chyme. There are proteases in the small intestine too, but there are more kinds and peptidases. The protein feels that hydrolysis has started again and it gradually turns into amino acids and small peptides.
"So this is trypsin." He thought.
The protein is no longer protein, it begins to be absorbed by the intestinal cilia and little by little enters the blood vessels of this body.
"My journey is over," protein thought.