NUTRITIONAL-VALUE OF MICRO-ENCAPSULATED FISH OILS IN RATS

The nutritional value of a micro-encapsulated fish oil product has bee n investigated. Three groups of 10 male Wistar rats each were fed diet s containing 20 % (w/w) of fat, and only the type and form of the fat added was different; In the test groups 5 % (w/w) of fish oil either a s such or in a micro-encapsulated form was incorporated in the diets. The remaining fat was lard supplemented with corn oil to a dietary con tent of linoleic acid at 10 % (w/w). The control, group received lard and corn oil only. A mixture similar to the dry matter in the micro-en capsulated product was also added to the diets not containing this pro duct. The uptake of marine (n-3) polyunsaturated fatty acids (PUFA) fr om both types of fish oil supplement was reflected in the fatty acid p rofiles of liver phosphatidyl cholines (PC), phosphatidyl ethanolamine s (PE), triglycerides (TG) and cardiolipin (CL). A suppression of the elongation of linoleic acid leading to a higher concentration of this fatty acid in liver PC and PE was also observed. The concentration of total lipids, triglycerides, cholesterol and phospholipids in liver wa s similar in all groups. Supplements of long chain (n-3) PUFA did not influence the concentration of plasma TG but lowered the level of plas ma cholesterol. No change in the oxidative status, measured as glutath ione peroxidase activity and cytochrome P450 concentration in the live r, was found after feeding with fish oil either directly or in the mic ro-encapsulated form. Intake of (n-3) PUFA lowered the concentration o f vitamin E in plasma while the content of vitamin E in the liver was unchanged. Overall, fish oil and microencapsulated fish oil resulted i n the same fatty acid pattern in the major lipid classes and the same concentrations of liver and plasma lipids. Furthermore, supplementatio n of fish oil or microencapsulated fish oil did not induce oxidative s tress when the diets were supplemented with ambient concentrations of antioxidants. It is concluded that micro-encapsulated fish oil is suit able for increasing the intake of(n-3) PUFA by fortification of normal daily food ingredients.