The color of a plastic twist tie or tag on a loaf of bread can actually tell you the day on which the bread was baked. In the United States, the common color scheme is blue for Mondays, green for Tuesdays, red for Thursdays, white for Fridays and yellow for Saturdays. Though it's not clear why the system does not include Wednesdays or Sundays, some say that it is because bakers used to not work on those days.
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