Studies on Trihalomethanes Precursors in Wastewaters of Factories -Flavanones in WasteWaters of Satsuma Mandarin Cannery

Trihalomethanes formation potential (THMFP) in wastewaters of Satsuma mandarin (Citrus Unshiu Marc.) cannery was the highest among food processing plants tested. Then, it was assumed that flavanones in Satsuma mandarin would be one of the main trihalomethanes precursors. In order to demonstrate the assumption, THMFP of flavanones and the flavanones (hesperetin and naringenin) in wastewaters were determined. And THMFP contribution ratio (THMFP calculated on the basis of the amounts of flavanones vs. THMFP in wastewaters) was estimated. The main results of the research were as follows. 1. Faavanones in Satsuma mandarin had more than 100μg·mgC-1 of THMFP per carbon and were found in processing unit operation waters. Especially separating operation water was the main source of flavanones. But flavanones were not found out in water treated with activated sludge. 2. The range of THMFP contribution ratios for all processing unit operation waters was from 10% to 92%.