Effects of bleaching and deodorization processes of beef tallow on cholesterol removal by lecithin treatment.

The effects of treatment with commercial lecithin followed by bleaching and deodorization processes on cholesterol reduction (removal) of Iranian beef tallow were studied. Steam-rendering extracted fat was subjected to lecithin treatment and the effects of four variables, i.e., ratio of lecithin to tallow (1:5, 1:10, 1:20 and 1:30 w/w), stirring time (0.5, 1.5, 3, 6 and 12 h), stirring rate (200, 500, 1,000 and 1,250 rpm) and ratio of lecithin to water (1:2, 1:5 and 1:10 w/v) were investigated. The results showed that cholesterol removal is increased with increasing the lecithin to tallow ratio and the stirring rate. Increasing stirring time up to 1.5 h increased cholesterol removal; however, longer times did not have any significant effect on it. The ratio of lecithin to water did not have any significant effect on cholesterol removal, either. It was concluded that up to 43% of the tallow cholesterol content could be removed by lecithin. Treatment with lecithin increased tallow acidity and color but did not have any effect on the peroxide value (PV). It is proposed that since tallow, as a slaughterhouse by-product, is not expensive, by this method we can improve its eating quality for use in dietary or industrial applications.