like limonin and naringin. Refining is commonly done by treat-
ment of the crude oil with a slight excess of alkali over the
amount necessary to react with the free fatty acids in the oil.
 Experiments in our laboratory on commercial crude citrus
seed oils have shown free fatty acid contents of 0.3% to 1.4%.
Refining losses determined by a standard A.O.C.S. procedure
(2), Method Ca 9f 57, were 0.8% to 3.5% depending on the
initial free fatty acid content. Economies of losses through re-
fining should dictate that crude citrus seed oils must be produced
with the lowest possible content of free fatty acids and other


* ~: :jjc ~.: I


-~.-~ --


Figure 2. Phantom view of four-high stack cooker and shaft arrangement of
 a continuous mechanical screw press. (Courtesy of the French
 Oil Mill Machinery Co., Piqua, Ohio.)

 15


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