Evidence backs new soy protein

US soy processor Central Soya reported that a study carried out by researchers at the University of Massachusetts shows that consumption of Alpha protein, a new soy protein ingredient, significantly lowered total and LDL blood cholesterol in animals.

For decades, nutritional studies have indicated that including soy protein in the diet reduces cholesterol levels. The higher the cholesterol, the more effective soy proteins are in lowering that level. However, many of these studies used highly processed soy protein ingredients, noted the company.

The researchers were interested in how the addition of Alpha-soy protein, a soy protein ingredient that more closely resembles the way proteins are naturally found in soybeans, to the diet would lower cholesterol compared to casein (a reference protein and the main protein in milk).

"Alpha protein is minimally processed, which helps to retain the natural solubility properties other soy proteins lose during processing,"​ said Kent Holt, director of protein marketing - speciality products America. "Alpha soy proteins also have one of the highest naturally occurring isoflavones levels found in soy proteins."​

For 6 weeks, hamsters in the study ate one of four diets containing 25 per cent protein. In one diet, all the protein came from soy and in a second diet, all the protein came from casein. The protein in the remaining two diets contained either a 25/75 or a 50/50 blend of soy protein and casein.

Total and LDL blood cholesterol levels were significantly lower in animals that consumed at least half their protein from soy compared to animals that consumed all their protein from casein, according to the company. In addition, when animals consumed all their protein from soy, liver cholesterol levels were lower compared to the casein-fed animals.

"Alpha soy protein had a powerful cholesterol lowering effect in the animals we studied. We are currently conducting a clinical trial to determine if similar effects will occur in humans,"​ commented Dr Robert Nicolosi, who conducted the research for Central Soya​.

Alpha soy protein can be used to formulate products that meet the FDA's soy protein health claim. "With the soy protein health claim on a package label, manufacturers are able to promote their products in the rapidly growing functional foods market,"​ said Holt.

Central Soya, based in Fort Wayne, Indiana, is a leading processor of oilseeds in North America, and sells soy protein concentrates and lecithins globally. It has 28 operating locations in the United States, Canada, Denmark and France and employees over 2,000 people. Parent company Cereol gained net sales of € 5.2 billion in 2001.