One hamburger contains the meat of up to approximately 100 cows. This is due to how ground beef is processed: cuts of beef that are not desired to be used in their whole state for steaks or roasts, for example, are gathered and ground up in a tenderizer. This compilation of scraps makes it likely that a package of ground beef may contain meat from many cows. The cheapest varieties of ground beef are often used for low cost hamburgers for fast food restaurants and will generally be the most likely to contain the highest number of less desirable scraps of beef from 100 cows or so.
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