Integrated chitosan-based whey processing for simultaneous annatto decolorization, protein delipidation, and nutraceutical phospholipid recovery

The main objective of this project was to develop an integrated chitosan-based whey processing scheme for annatto decolorization, protein delipidation, and nutraceutical phospholipid recovery.;Separation of lipids and lipoproteins from liquid Cheddar cheese whey by ultracentrifugation demonstrated that annatto pigments were dissolved or bound in lipophilic components of the whey. Treatment of liquid Cheddar cheese whey with a patented lipid-chitosan complexation process effectively removed lipids and annatto pigments from whey. Total lipids in the whey fractions were determined gravimetrically after extraction with organic solvents. Annatto pigments in the fractions were assayed by high performance liquid chromatography. The chitosan-lipid complex was composed of about 20% lipids and contained about 88% of the annatto pigments found in the intact parent whey. The delipidated liquid whey fraction did not contain detectable annatto, and contained only about 0.02% lipids.;Release of whey complexed lipids to recycle chitosan was then achieved by treatment of the chitosan-lipid complex with proteases. Sequential hydrolysis of the complex with pepsin, tripsin, and subtilisin was effective in separating lipids from chitosan, so it can be recycled. The added cost of the chitosan process can be off-set by recovery of lipids from the chitosan-lipid complex. Fractionation of the lipids in the chitosan-complex showed that 20% of the total lipids are phospholipids, which consisted of 19% phosphatidyl ethanolamine, 21% phosphatidyl serine and phosphatidyl inositol, 30% phosphatidyl choline, 25% sphingomyelin, and 2% lysophosphatidyl choline. Such profile was preserved in the lipids released upon proteolysis of the complex. In conclusion, removal of lipids by precipitation with chitosan, followed by treatment with proteases is an effective way of removing residual annatto pigments from liquid whey and recover dairy lipids with potential value as ingredients in nutraceuticals and cosmetics.