|MadSci Network: Biochemistry|
Dear Mr. Owens: The acids that account for the acidity of tomatoes are citric, malic, lactic, ascorbic (Vitamin C)and polycarboxylic. Their concentrations vary from several parts per million (ppms) to 1-20 mg/100 g of fresh tomato. The concentrations will also vary depending on the variety, cultural practices and the environmental conditions during the growing season. I hope this answers your question. Al Bushway Professor of Food Science
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