It’s quite rare to find blood spots in eggs sold in supermarkets . In fact, less than 1% of commercial eggs contain them . Why? Because before they reach our kitchens, eggs are scrutinized using a process called “candling .” This uses a bright light to detect internal defects and abnormalities . Most eggs with blood spots are therefore discarded before being put on the shelves .
On the other hand, if you eat farm-fresh eggs , you’re likely to come across them a little more often. These eggs don’t always go through the same testing process. Additionally, brown eggs are more likely to have these spots , simply because their darker shells make candling less effective.