M. Jakobsson et B. Sivik, OXIDATIVE STABILITY OF FISH-OIL INCLUDED IN A MICROEMULSION, Journal of dispersion science and technology, 15(5), 1994, pp. 611-619
Handling and storage of polyunsaturated lipids is a difficult problem
due to oxidation. Oxidation products cause reduction in sensoric quali
ty and can also have negative physiological effects, all of which obst
ruct the use of otherwise nutritionally important compounds. Therefore
it is important to find techniques to prevent this quality deteriorat
ion. It is shown in this work that the oxidation of a fish oil can be
decreased if the oil is transformed into a microemulsion with ascorbic
acid and alpha-tocopherol used as antioxidants. Tocopherol will be lo
calized in the hydrocarbon chain region whereas ascorbic acid is accum
ulated in the polar parts of the microemulsion. ''Packaged'' in this w
ay the oxidation of the oil is retarded. The peroxide and anisidine va
lues are both drastically decreased when compared to a pure fish oil,
which has been demonstrated by keeping samples at 40-degrees-C for 18
days. Furthermore an improved effect was seen when ascorbic acid was s
olved in glycerol instead of in water.