The researchers' study -- published in the Journal of the Science of Food and Agriculture -- indicates that current sea buckthorn juice extraction methods result in poor quality juice, with low levels of antioxidants. However, a new technique using high-speed centrifugal force to separate the fruit juice from the solid berry sludge yields higher quality juice, the researchers found.
Sea buckthorn juice -- widely used in Mongolia, China, Tibet and Russia in health drinks and other products -- has been shown to contain high levels of antioxidant chemicals which boost heart health by blocking the artery-clogging action of "bad" LDL cholesterol.
When LDL cholesterol becomes oxidized, it sticks to the walls of blood vessels, causing potentially fatal blockages. However, previous research has shown that the antioxidants in sea buckthorn juice can prevent the cholesterol from oxidizing.
An analysis of the centrifuge-extracted juice found that it contained more than 40 percent of the original polyphenol (plant chemicals that are responsible for pigment) content of the whole berry, as well as 50 percent of the flavonoids (plant antioxidants) and 70 percent of the vitamin C.
According to British Heart Foundation nutritionist Sara Stanner, "The antioxidants in sea buckthorn juice and pulp may protect the heart by reducing harmful chemicals in the blood."
Stanner said the pulp oil from sea buckthorn contains healthy unsaturated fatty acids and plant sterols -- plant-based cholesterol that competes with unhealthy dietary cholesterol for absorption in the body, often resulting in lower total cholesterol.
"In addition, there is evidence that sea buckthorn juice might help protect 'bad' [LDL] cholesterol from oxidation, a process which is involved in the development of coronary heart disease," Stanner said.
"The oil has also been shown to have a possible benefit in reducing the tendency of blood to clot, but more research is needed to clarify whether adding it to foods can have any real impact on reducing risk of heart disease."