Method for extracting high-quality krill oil from krill

A method for extracting a high-quality krill oil from krill, comprising the following steps:

• S1, performing an extraction on the krill with an organic solvent, and collecting an extracting solution;
• S2, adding alkaline water to the extracting solution to enable a free fatty acid to form a fatty acid salt to be separated from an oil phase, and performing an oil-water phase separation, and collecting the oil phase;
• wherein in the step, the reaction is carried out at 45-55° C., a solute in the alkaline water is an alkaline compound, the alkaline compound consisting of sodium carbonate or sodium hydroxide;
• when the alkaline compound is sodium hydroxide, the actual addition amount of the sodium hydroxide is 0.9-1.2 times of the theoretical addition amount of the sodium hydroxide;
• and
• when the alkaline compound is sodium carbonate, and the actual addition amount of the sodium carbonate is 0.5-1.5 times of the theoretical addition amount of the sodium hydroxide;
• and
• the theoretical addition amount of the sodium hydroxide is MNaOH=Moil×AV×7.14×10−4, wherein MNaOH is the theoretical addition amount (unit:
• kg) of the caustic soda, Moil is a mass (unit:
• kg) of a krill oil in the extracting solution, and AV is an acid value (unit:
• mg KOH/g) of the krill oil in the extracting solution;
• S3, purifying the oil phase to obtain the high-quality krill oil.