Hey Ms. Linda! These are great questions, especially if you are learning how to make authentic Japanese dishes. I believe she wrote on the video that she washed the eggs well before she froze them to prevent salmonella because when the eggs frozen, the shells cracked open and that would expose the yolk and whites to any bacteria. The yolks were perfectly round so they would keep their shape and pickle better. By using certain 'pickling agents' - soy sauce and mirin, they help cure the yolks and toughen the vitelline membrane of the yolk. As far as straining the left over yolks, they were just just added to the miso soup from the storage dish. She cracked the eggs for the rolled eggs in a bowl and then added the surimi and other ingredients to the eggs, but no straining. The only thing she strained was the dashi broth for the miso soup. Hope that helps. LOL! I had to watch the video a couple of times so I could remember how the ingredients were prepared too. Have a great week! 🤗