Determine the Foos Sources of cyanocobalamin?

Vitamin B_I2 is unique among vitamins in the sense that it is mostly found in foods of animal origin but is not generally present in plant products as also is evident from the  food sources highlighted herewith and in Figure.

• Rich sources: Liver (goal, sheep, ox, pig).
• Good sources: Meal, fish, egg, kidney, brain.
• Fail Sources: Fresh milk, milk powder and cheese.

Most microorganisms, including bacteria and algae, synthesize vitamin B₁₂, and they constitute the only source of the vitamin. The vitamin B_I2 synthesized in microorganisms enters the human food chain through incorporation into food of animal origin. In many animals, gastrointestinal fermentation supports the growth of these vitamin B₁₂ synthesizing microorganisms, and subsequently the vitamin is absorbed and incorporated into the animal tissues. This is particularly true for the liver, where vitamin B₁₂ is stored in large concentrations. Products from herbivorous animals, such as milk, meat  and eggs, thus constitute important dietary sources of the vitamin.

Humans, therefore, derive dietary vitamin B₁₂ almost exclusively from animal issues or products (i.e. milk, butter, cheese, eggs, meal, poultlry). Considering the fact that this vitamin intake can only be assured through animal food sources, vegetarians, therefore, have to be very cautious about meeting their vitamin B₁₂ requirements, and are hence often advised to increase their milk intake or take vitamin B₁₂ as a supplement.