Removal Effect of Oxidation Products in Anchovy Oil by Alkali Refining

In this study, the crude fish oil of anchovy was used as experimental material, and the total oxidation value was selected as the indicator of evaluation. Under the condition of nitrogen or high vacuum, the alkali refining was used to remove oxidation products in anchovy fish oil.Through the Box-Behnken response surface analysis method, the four process parameters of excess alkali, lye concentration, temperature and reaction time were optimized to determine optimum alkali refining of anchovy oil. Metal elements in anchovy oil were detected by inductively coupled plasma mass spectrometry (ICP-MS). The results showed that the optimum alkali refining process conditions were 0.45% of excess alkali, 3.65% of lye concentration, 65℃ of temperature and 40 min of reaction time. The total oxidation value (TV) of anchovy oil decreased from 123.48 to 59.35 and the acid value of fish oil decreased from 2.1627 to 0.8843 mg KOH/g. The removal rate of Fe element was 73.70%. The removal rate of As element was 97.04%. Therefore, the optimized alkali refining process conditions could maximize the removal of the oxidation products in the fish oil, which presented a reference to industrial production of fish oil regarding to the removal of oxidation products in fish oil.