He attributed this to differences in the way fat is stored in the ingredients. "In soybeans, you have almost 20% fat, and therefore a lot of that fat is just stored as regular triglycerides, and relatively easy to get to. In the other ingredients, in particular the corn germ and the DDGS, some of the fat is encapsulated by fibre, which makes it more difficult for the enzymes to digest."
According to study results, the true ileal digestibility of corn oil was greatest at 95.4%. Among intact sources of fat, the fat in full-fat soybeans (85.2%) and HP DDG (76.5%) was the most digestible. Digestibility of fat was lowest in DDGS (62.1%), high-oil corn (53.0%), and corn germ (50.1%).
根据研究结果，玉米油在回肠真消化率是最高的达到95.4%，在完整来源的的脂肪（在原料中的油脂没有被提取情况下的脂肪），全脂大豆的脂肪（回肠真消化率为85.2%），高蛋白DDG（玉米干酒糟76.5%）是最容易消化的。 DDGS (玉米酒糟及其可溶物脂肪回肠真效率62.1%)，高油玉米 (53.0%)，和玉米胚芽 (50.1%)。
"From a nutritional point of view, there would be a clear advantage if we could first extract the fat and then add it to the diet as corn oil rather than leave it in the ingredients. Whether such an approach would be economical would depend on the cost of extracting the oil from corn germ and other ingredients," Stein said.