Bread baking thiamine

Bread baking losses—In baking bread, 15 to 20% of the original thiamin content is lost. 

Baking of white bread may result in thiamin loss of 20 percent. Thiamin loss in milk... 

Martmez-Villaluenga, C., Michalska, A., Frias, J., Piskula, M.K., Vidal-Valverde, C., and Zielinski, H., 2009. Effect of flour extraction rate and baking on thiamine and riboflavin content and antioxidant capacity of traditional rye bread. Journal of Food Science. 74 49-55. 

The vitamins of the B group are lost to different extents during baking. In white bread, the losses amount to 20% (flour type 550)—50% (flour type 1150) of thiamine, 6-14% of riboflavin and 0-15% of pyridoxine. 

Like other water-soluble vitamins, thiamin is readily lost by leaching into cooking water. Furthermore, it is unstable to light and, although bread and flour contain significant amounts of thiamin, much or all of this can be lost when baked goods are exposed to sunlight in a shop window. 

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