|MadSci Network: Biochemistry|
Very few foods are alkaline in reaction, most are acidic. Egg white and baking soda are two compounds found in the kitchen that have an alkaline reaction, otherwise foods are acidic. I don't have the specific information on spices, but I would safely assume they would be acidic if measured. This is in contrast to the effect of foods on the urine after they are consumed. In the early part of the 20th century dietitians were interested in a food's ability to be "acid-forming" or "base-forming" referring to their effect on the pH of the urine. Meat was found to be "acid-forming" presumably because of the mineral content of amino acids especially sulfur and the formation of some sulfuric acid during excretion and the acid forming properties of chloride and phosphorus. By contrast vegetable material tends to be alkaline-forming. Thus, it is important to know what application you wish to make of information about the pH of foods.
A list of the pH of common foods can be found in the text Basic Foods by June C. Gates c. 1976 (New York: Holt, Rinehart and Winston), and an up-to-date discussion of "acid ash" and "alkaline ash" diets is presented on page 843 of Krause's Food, Nutrition and Diet Therapy by L. Kathleen Mahan and Sylvia Escott-Stump, c 2000 (Philadelphia and Tokyo, WB Saunders Co.) and in the journal article Dwyer J et al. Acid/Alkaline ash diets: Time for assessment and change J Am Diet Assoc 85:841, 1985.
Phyllis J. Stumbo University of Iowa Iowa City, Iowa
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