Step 5: Replace Vinegar
After about 24 hours has passed you should replace the vinegar.
Carefully pour out the vinegar.
Once all of the old vinegar is removed pour in new vinegar so that again, the egg is completely cover.
As you can see in my picture I did not bother removing all of the foam, you can if you want too.
You will be able to observe that the shell is thining and patches of yellow (the yolk) will be seen through the thinning egg shell.