Fractionation of squalene from amaranth seed oil

Amaranth seed oil was fractionated in a bench-scale short-path distillation unit to obtain fractions rich in squalene. Fractionations were conducted with degummed amaranth oil, alkali-refined amaranth oil, and simulated amaranth oil. Squalene concentration was increased about sevenfold with a squalene recovery of 76.0% in the distillate when degummed amaranth oil was fractionated at 180 degrees C and 3 mtorr vacuum. Free fatty acids codistilled with squalene, lowering the squalene content of the distillate, and resulted in a semisolid distillate at room temperature. Alkali-refining was subsequently used to reduce the free fatty acid content before fractionation. A simulated oil (7% squalene/93% soybean oil) and alkali-refined amaranth oil were fractionated at three temperatures (160, 170, and 180 degrees C) and five vacuum settings (10, 100, 200, 400, and 600 mtorr). The highest squalene recoveries from simulated oil and alkali-refined amaranth oil were 73.4 and 67.8%, respectively, both at 180 degrees C and 100 mtorr, which translates to 12.1- and 9.2-fold increases in squalene concentration, respectively. The squalene recovery of the alkali-refined amaranth oil at 180 degrees C was not significantly different at 10 mtorr vs. 100 mtorr. The results of this study can be used as a component to assess the economic feasibility of fractionating amaranth seed for starch, oil, meal, and squalene.