In its November World Agricultural Supply and Demand Estimates, the U.S. Department of Agriculture projected U.S. 2010-11 rice milling yield at a record low 67.5%, down 2% from its October projection and down 3% from 2009-10.

“The most significant revision this month to the U.S. rice balance sheet was a reduction in the 2010-11 milling rate to 67.5% from the previous forecast of 68.86%,” the U.S.D.A. said in its Nov. 10 Rice Outlook. “This is the lowest milling rate since at least 1960-61 when U.S.D.A. first began reporting milling rates. The reduced milling rate is largely due to extremely hot weather in August in much of the South.”

As a result of the unprecedented low milling yield, the USA Rice Millers’ Association issued a statement supporting the U.S.D.A. projection and noting the low milling yields were concentrated in the U.S. long-grain rice crop grown mainly in Arkansas, Louisiana, Mississippi, Missouri and Texas.

“Lower long-grain milling yields are responsible,” the association said. “Individual reports from Rice Millers’ Association members corroborate U.S.D.A.’s projection.”

“Lower long-grain milling yields are having a significant impact on milling operations,” R.M.A. said. “In order to mill a quantity of whole-kernel rice, more rough rice must be used and the rough rice must be milled at a slower rate. While the quantity and appearance of the finished product is not impacted, this situation has reduced significantly the day-to-day output of milled rice. In 2009, long-grain rough rice yielded an average of 60 lbs of whole-kernel rice for every 100 lbs milled. R.M.A. expects the 2010 whole-kernel yield will average much lower, perhaps 10% to 15%.”

Despite the lower milling yield, rice supply was expected to be ample in 2010-11. The U.S.D.A. forecast 2010 U.S. rice production at a record 241.6 million cwts, up 10% from 2009. Global rice production was forecast at a record 451.4 million tonnes in 2010-11, up 2% from 2009-10.