The effects of refining process and ß-cyclodextrin treatment on the cholesterol reduction in beef tallow

Presence of cholesterol in the diet is considered a risk factor for cardiovascular diseases. One of the most effective methods for lowering the incidences of these diseases is removal of cholesterol from foods including animal fats. The objective of this study was to investigate the effects of refining process and ß-cyclodextrin (ß-CD) treatment of tallow on the reduction of cholesterol,as well as changes in other physical and chemical characteristics of this fat in the laboratory scale.

After preliminary preparation of fresh beef tallow, rendering and filteration, the refining process employed to the resultant fat similar to the common industrial conditions and also for the removal of cholesterol, ß-CD treatment was applied between bleaching and deodorization processes.The physical and chemical characteristics of crude and refined fats were determined. The results obtained for acid value, peroxide value and cholesterol content were compared for three different processes: (a) refining, (b) ß-CD treatment, and (c) combined refining and ß-CD treatment. Changes in the fatty acid composition of tallow before and after processing were also investigated.All determinations were performed in triplicate and mean values reported.

The results showed that ß-CD treatment alone can reduce cholesterol content to 81%,and refining process also reduced this factor to 22%. Refining and ß-CD treatment together reduced cholesterol content significantly and satisfactorily in tallow to 90%, without any change in the fatty acid composition (p<0.05). The results showed that ß-CD treatment, deodorization, neutralization, phosphoric acid treatment, and bleaching are the most effective in cholesterol reduction, respectively.Statistical analyses indicated that there are significant differences between cholesterol contents of tallow in three different processes and also during refining process (p<0.05).Also ß-CD treatment reduced acid value of tallow significantly and satisfactorily but slightly increased peroxide value of this fat but not significantly.

According to our results, combined refining and ß-CD treatment is recommended in order to reduce the cholesterol content and maintaining quality characteristics of tallow which is not used in oil industry in Iran. Consequently,application of this technology will lead to a product with appropriate nutritional quality, either for direct use or as a blend with other oils.This will be economically justified, as well as being hygienic and preventing environmental contamination.